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SOO LHERN CALIFORNIA ACADEMY OF SCIENCES

LLETIN

Volume 97 Number 1

BCAS-A97(1) 1-48 (1998) APRIL 1998

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Date of this issue 9 April 1998

Bull. Southern California Acad. Sci.
97(1), 1998, pp. 1-8
© Southern California Academy of Sciences, 1998

Temporal Changes in Diet and Foraging Habitat of California
Killifish (Fundulus parvipinnis) in Marina del Rey, California

Kristine Behrents Hartney and Lusine Tumyan

Department of Biology, Occidental College, Los Angeles, California 90041

Abstract.—Feeding habits of the California killifish, Fundulus parvipinnis Girard,
in Marina del Rey were examined relative to season and prey availability. Tem-
poral changes in diet coincided with ontogenetic shifts in foraging habitats. Ju-
venile fish fed selectively on relatively rare planktonic harpacticoid copepods and
surface dwelling insects, whereas diets of adults were dominated by benthic prey
taxa, principally tanaids. The seasonal availability of some prey taxa and the active
selection of others associated with a particular foraging habitat affected the type
and size of prey consumed. Our results indicate that patterns of prey use are not
simple responses to seasonal changes in prey abundance.

The California killifish, Fundulus parvipinnis Girard, is a common resident in
shallow protected waters along the California coast from Morro Bay, California
to Almejas Bay, Baja, Mexico (Miller and Lea 1976; Swift et al. 1993). While
most abundant over muddy/sand bottoms of bays and estuaries, this small (less
than 115 mm SL), short-lived (18 mo) fish may also persist in freshwater streams
(Hubbs 1916; Miller 1939, 1943; Swift et al. 1993) and hypersaline ponds (Feld-
meth and Waggoner 1972). Because of its ability to tolerate a broad range of
environmental conditions, this species has been the focus of numerous physio-
logical studies (Keys 1931; Wells 1935a, 1935b; Doudoroff 1945; Carpelan 1961;
Hubbs 1965; Valentine and Miller 1969; Feldmeth and Waggoner 1972; Bagarino
and Vetter 1992, 1993). However, far less consideration has been given to studies
of its natural history, particularly feeding habits, despite its numerical dominance
and important role in the structure and trophic dynamics of estuarine and bay
communities (Fritz 1975; Allen 1980, 1982).

Trophic analyses of killifish collected monthly from Anaheim Bay, California
from November 1969 through January 1970 by Fritz (1975) and of fish sampled
bimonthly from upper Newport Bay from January through November 1978 by
Allen (1980) indicate that killifish are lower trophic level carnivores consuming
primarily small crustaceans (e.g., ostracods, harpacticoid copepods, gammarid am-
phipods), dipteran and hemipteran insects (Fritz 1975; Allen 1980), polychaetes,
and gastropods (Allen 1980). However, changes in dietary patterns over time
within a particular locale (Fritz 1975; Allen 1980) and differences in diets between
these locations indicate that both temporal and spatial factors influence the type
of prey consumed by these fish. While differences in diet within and between
these sites may simply reflect a response by these fish to varying patterns of
resource abundance (Moyle 1976), patterns of diet choice may also be driven by
selective feeding behaviors that may change with age (ontogenetic Shifts) and
prey characteristics (Kaiser and Hughes 1993). Therefore, the

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study were to assess the feeding habits of Fundulus parvipinnis that reside in
Marina del Rey relative to season and to examine the relationship of prey type,
size, and availability to dietary choices.

Methods

All field work was conducted in water depths less than 3 m just offshore of
the public swimming beach located at the extreme western end of Basin D within
Marina del Rey. Killifish were collected following high tides on two occasions,
March 30, 1995 (1300 to 1430 hrs) and October 13, 1995 (1130 to 1300 hrs)
using a 30.5 m beach seine (4.8 mm bag mesh) that was initially deployed about
10 m parallel to shore and then slowly drawn up onto the beach. A total of 129
and 150 fish were captured and immediately fixed in 10% formalin during March
and October respectively.

On the October sampling date, prey resource samples were also collected from
the water column and: substratum in the same general area as fish captures. To
obtain an estimate of planktonic prey available to fish, the water column was
sampled by SCUBA divers propelling a plankton net (0.33 mm mesh) with a 0.5
m diameter mouth opening for two minutes through midwater depths (0.5 to 2.5
m). Three replicate tows were made and all samples were immediately fixed in
4% formalin. Estimates of benthic prey available were obtained by driving a 12.5
cm long benthic core (10 cm internal diameter) completely into the substratum.
Three replicate cores were taken and entire samples fixed in 10% formalin. Each
benthic sample (982 cm?) was later washed through a 0.5 mm sieve and only the
larger fraction was retained for further analysis.

In the laboratory, the standard length of each killifish was measured to the
nearest 0.1 mm using Vernier calipers and its age determined by reading scale
annuli (Cailliet et al. 1986). The entire gut and gonads were then removed from
a subsample of fish selected at random from March (N = 30) and October (N =
47) collections. The dietary analysis of 30 fish taken from the March sample was
considered adequate for determining large scale differences in diet between sea-
sons, however a greater number of fish (47) were analyzed from the October
sample to ascertain fine scale patterns of prey selection within a single time period.
All prey were removed from each gut and identified to the lowest taxon practi-
cable. Whole animals or heads (when prey were not intact) were counted and the
greatest length of up to 25 intact individuals per taxon (as randomly encountered)
was measured to the nearest 0.01 mm using an ocular micrometer. Gender and
reproductive status of killifish were determined by examining the gonads for pres-
ence of eggs or sperm and scoring their stage of maturity according to the methods
described by Cailliet et al. (1986). Reproductively immature fish less than one
year old were considered juveniles.

The contents of planktonic and benthic resource samples collected in October
were identified, counted and measured using methods similar to those described
for gut content analysis. However, each planktonic resource sample was split twice
with a Folsom plankton splitter so that all organisms in only one quarter of the
sample were completely identified, counted, and up to 25 individuals per taxon
measured. Numbers and sizes of prey for the entire plankton sample were later
extrapolated. Invertebrates (>0.5 mm) contained in each benthic resource sample
were separated from sand by gently floating them away from inorganic materials

FORAGING PATTERNS OF CALIFORNIA KILLIFISH 3

100
March 1995 October 1995
80

Number (%)

. harpacticoid copepods
. tanaids

gammarid amphipods
. nematodes

diptera

. hymenoptera

. hemiptera

. diplura

eggs

Frequency of Occurrence (%)

A
B
Cc.
D
E.
F
G
H
I.

100
A B Cc D = F I A B Cc D E F G H

Fig. 1. Percent composition of prey by taxon, number (%) and frequency of occurrence (%) in
diets of 29 killifish collected in March 1995 (N = 2107 prey) and 40 killifish collected in October
1995 (N = 2097 prey).

in distilled water. The remaining inorganic fraction was then examined for any
misplaced organisms, which when found were combined with the organismal
fraction that was analyzed in its entirety.

To examine the relationship between prey consumed relative to prey available,
electivity coefficients were determined for all available prey taxa collected in
October resource samples using Ivlev’s Electivity Index (Ivlev 1961). While the
sign and magnitude of resulting coefficients (from —1 to +1) were used as in-
dicators of possible avoidance (negative values), random (zero values) or pref-
erential (positive values) selection of specific prey taxa, the significance of these
food preferences was statistically evaluated using a Chi Square analysis described
by Pearre (1982). For these analyses, the total number of prey collected from the
water column and substratum were combined and considered as a single resource
base.

Results

Temporal Changes in Diet and Foraging Habitat

Although the dietary spectrum of prey taxa consumed by fish collected in
March and October was similar, there was a striking difference between them in
the dominant types of prey eaten (Fig. 1). The diets of killifish in March were

4 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

dominated by benthic prey species, principally tanaids, and the nearly complete
absence of planktonic or terrestrial prey (insects) in diets suggested that killifish
foraged along the bottom at this time of year. In contrast, planktonic harpacticoid
copepods were by far the most common and numerically abundant prey consumed
by fish in October and insects were consumed with a relatively high level of
frequency. The occurrence of these prey types relative to others suggest that in
the fall of the year, fish fed in the water column or from the surface. The mean
size of prey (+1 standard deviation) consumed by killifish in March (x = 1.85
+ 0.96 mm) was significantly greater than the mean size of prey consumed in
October (* = 0.55 + 0.52 mm; t = 54.7, df = 3244, P < 0.01).

Overall, reproductively mature fish collected in March were significantly larger
(x = 6.4 + 0.7 cm SL) and older (>1 yr) than the sexually immature juveniles
(x = 3.9 + 0.9 cm SL) that were collected in October (t = 28.5, df = 277, P<
0.01). These size differences were maintained in subsamples of fish randomly
selected for gut content analysis (March x = 6.3 + 0.8 cm SL; October * = 3.9
+ 0.9 cm SL). Of the 30 fish collected in March that were selected for gut content
analysis, 29 contained prey, whereas 40 of the 47 fish selected from October
samples had prey in their guts.

Availability and Selectivity of Prey

In general, prey types were unique to a particular resource sampling area and
taxa composing planktonic and benthic groups were easily separated from one
another on the basis of relative differences in their numerical representation in
samples taken from the water column and substratum (Table 1). Plankton samples
were dominated by calanoid copepods, while organisms generally associated with
the substratum such as tanaids, polychaetes, nematodes, and gammarid amphipods
dominated benthic samples. Taxon specific differences in size and distribution
strongly affected size frequency distributions of available prey (Fig. 2) such that
the mean size of prey available from the water column (x = 0.82 + 0.18 mm)
was significantly less than that of benthic (« = 3.75 + 2.35 mm) prey (t = 45.3,
df = 1323, P < 0.1). Reflecting either sampling bias or low frequency of oc-
currence, no insects were collected in resource samples.

Killifish consumed few prey in direct proportion to their availability in the
water column or substratum (Table 1). Significant electivity values indicate that
in October, killifish preferentially selected relatively rare small harpacticoid co-
pepods from the water column while they avoided relatively abundant calanoid
copepods and numerically abundant benthic taxa (tanaids and polychaetes). Even
though terrestrial insects were not represented in resource samples, the frequent
appearance of insects in killifish guts indicate that they were probably selected
whenever they were encountered. The choice of small planktonic harpacticoid
copepods by fish in October strongly influenced the size range (0.2 to 5.9 mm)
and mode (0.4 mm) of prey found in the guts relative to the range of sizes (0.1
to 3 mm) and mode (0.8 mm) of all planktonic prey available (Fig. 2). Although
capable of consuming relatively large prey such as insects, they apparently avoid-
ed benthic prey (e.g., tanaids) within a similar size range. Thus, differences in
the size frequency distributions of prey consumed relative to those of available
prey resulted from the active selection of some prey taxa over others rather than
the selection of large or small prey regardless of taxon or habitat.

FORAGING PATTERNS OF CALIFORNIA KILLIFISH

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6 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

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in October 1995 (N = 2097 prey) relative to prey available from the water column (N = 80740) and
substratum (N = 1326). Benthic prey resources distributed in amounts less than 1% among size
intervals from 6 to 12.8 mm are not displayed.

Discussion

Our results corroborate earlier descriptions of Fundulus parvipinnis as lower
level microcarnivores that primarily consume arthropods (crustaceans and insects).
Like others (Fritz 1975; Allen 1980), we observed marked seasonal changes in
the presence of certain prey types (most notably insects) that contributed to dietary
differences between warmer (Oct.) and colder (March) months. Yet, even within
constraints imposed by the seasonal presence of certain prey types, the distinctive
temporal changes we observed in the types of prey consumed by different size
classes of fish signaled an age related shift in foraging habitat.

Ontogenetic shifts in diet and foraging habitats are common among fishes (Kai-
ser and Hughes 1993) and are likely to play a significant role in patterns of dietary
choice by Fundulus parvipinnis. Although Fritz (1975) was unable to discern any
differences in diets or foraging habitats of killifish with age or season, our results,
like those of Allen (1980), indicate that juvenile killifish feed primarily on small
planktonic harpacticoid copepods and gradually shift to larger benthic prey as
they mature. Whether these ontogenetic shifts in diet are related to morphological
changes in mouth size and/or changes in feeding behaviors remains to be deter-
mined. However, the ability of juvenile fish to consume relatively large insects
indicate that they are not morphologically constrained from handling similarly
sized benthic prey.

Dietary changes were coincidental with changes in foraging habitat and sig-
nificant electivity values for fish obtained in October indicate that patterns of prey
use were not simply a response to the numerical abundance of prey. Instead, the
number, type, and size of prey consumed reflects the tendency of this species to
select a unique combination of prey taxa from all prey available. Preferences of

FORAGING PATTERNS OF CALIFORNIA KILLIFISH y;

Fundulus parvipinnis for small harpacticoid copepods and insects relative to nu-
merically dominant prey within similar size ranges at this time (e.g., calanoid
copepods and tanaids) could be related to a number of behavioral, functional,
nutritional, ecological, and/or energetic factors (Kaiser and Hughes 1993). How-
ever, the assessment of these variables during ontogeny would be necessary to
fully explain the value of habitat and diet changes as these fish grow larger.

For Fundulus parvipinnis that inhabit Marina del Rey, changes in foraging
habitats and selective feeding behaviors practiced within those habitats appear to
be primarily responsible for temporal changes in diet. However, other factors
including temporal and spatial changes in the availability and abundance of suit-
able prey may be involved as well. Variations in these factors may be one expla-
nation for dietary differences observed among fish collected at different sites and
times. For example, Fritz (1975) showed that killifish in Anaheim Bay fed pri-
marily as planktivores on harpacticoid copepods and ostracods in the spring and
while not excluding these taxa, utilized a greater proportion of amphipods and
insects as the year progressed. Allen (1980) reported that in addition to harpac-
ticoid copepods, ostracods, and insects, killifish in upper Newport Bay also con-
sumed polychaetes and gastropods frequently. The absence and relative rarity of
several of these groups from our resource samples (e.g., ostracods, amphipods,
and gastropods) and presence of others not seen in gut contents of fish collected
elsewhere (e.g., tanaids) suggests that the composition of available prey is highly
variable in time and space, and undoubtedly plays a role in prey selection of fish
residing in different locations.

Conclusions

Although sampling was limited to two months of the year (March and October),
temporal changes observed in the diet of killifish inhabiting Marina del Rey seem
to be related to seasonal changes in the availability of certain types of prey (e.g.,
insects) and to shifts in foraging habitat with age. Although the causes of onto-
genetic shifts in diet were not examined, a comparison of prey taxa consumed to
those available in October indicate that at least juvenile killifish actively select
certain prey taxa over others. We suspect that selective feeding is not limited to
a single life stage or location, however spatial and temporal variations in prey
availability are likely to influence prey choices and consequently dietary patterns
of fish collected at different times and/or sites.

Acknowledgments

This research was supported by a grant from the National Science Foundation’s
Young Scholars Program (ESI-9353874). We extend our thanks to the Occidental
College students enrolled in Biology 356, and to D. Pondella, G. Lattin, and A.
Simm for helping in the collection of March and October samples respectively.
A special thanks to A. Simm for his efforts sorting benthic samples.

Literature Cited

Allen, L. G. 1980. Structure and productivity of the littoral fish assemblage of upper Newport Bay,
California. Ph.D. Thesis, Univ. So. Calif., Los Angeles. 175 pp.

. 1982. Seasonal abundance, composition, and productivity of the littoral fish assemblage in

upper Newport Bay, California. Fish. Bull., 80:769—790.

8 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Bagarinao, T., and R. D. Vetter. 1992. Sulfide-hemoglobin interactions in the sulfide-tolerant salt
marsh resident, the California killifish Fundulus parvipinnis. J. Comp. Physiol. B, 162:614—
624.

. 1993. Sulphide tolerance and adaptation in the California killifish, Fundulus parvipinnis, a
salt marsh resident. J. Fish Biol., 42:729-—748.
Cailliet, G. M., M. S. Love, and A. W. Ebeling. 1986. Fishes. A field and laboratory manual on their
structure, identification, and natural history. Wadsworth Publishing Co., viii + 194 pp.
Carpelan, L. H. 1961. Salinity tolerances of some fishes of a southern California coastal lagoon.
Copeia, 1961:32-—39.

Doudoroff, P. 1945. The resistance and acclimatization of marine fishes to temperature changes. 6.
Experiments with Fundulus and Atherinops. Biol. Bull., 88:194—206.

Feldmeth, C. R., and J. P. Waggoner. 1972. Field measurements of tolerance to extreme hypersalinity
in the California killifish, Fundulus parvipinnis. Copeia, 1972:592—594.

Fritz, E. S. 1975. The life history of the California killifish Fundulus parvipinnis Girard, in Anaheim
Bay, California. Calif. Dept. Fish Game, Fish Bull., 165:91—106.

Hubbs, C. 1965. Developmental temperature tolerance and rates of four southern California fishes,
Fundulus parvipinnis, Atherinops affinis, Leuresthes tenuis, and Hypsoblennius sp. Calif. Fish
and Game, 51:113-—122.

Hubbs, C. L. 1916. Notes on the marine fishes of southern California. Univ. Calif. Publ. Zool., 16:
153-169.

Ivlev, V. S. 1961. Experimental ecology of the feeding of fishes. Yale University Press, 302 pp.

Kaiser, M. J., and R. N. Hughes. 1993. Factors affecting the behavioral mechanisms of diet selection
in fishes. Mar. Behav. Physiol., 23:105-118.

Keys, A. B. 1931. A study of the selective action of decreased salinity and of asphyxiation on the
Pacific killifish, Fundulus parvipinnis. Bull. Scripps Inst. Ocean., 2:417—490.

Miller, D. J., and R. N. Lea. 1976. Guide to the coastal marine fishes of California. Calif. Dept. Fish
Game, Fish Bull. 157,235 pp:

Miller, R. R. 1939. Occurrence of the cyprinodont fish, Fundulus parvipinnis, in fresh water in San
Juan Creek, southern California. Copeia, 1939:168.

1943. Further data on freshwater populations of the Pacific killifish, Fundulus parvipinnis.
Copeia, 1943:51-52.

Moyle, P. B. 1976. Inland fishes of California. Univ. California Press, viii +405 pp.

Pearre, S. Jr. 1982. Estimating prey preference by predators: uses of various indices, and a proposal
of another based on x’. Can. J. Fish. Aquat. Sci., 39:914—923.

Swift, C. C., T. R. Haglund, M. Ruiz, and R. N. Fisher. 1993. The status and distribution of the
freshwater fishes of southern California. Bull. So. Calif. Acad. Sci., 92(3):01—167.

Valentine, D. W., and R. Miller. 1969. Osmoregulation in the California killifish, Fundulus parvipin-
nis. Calif. Fish and Game, 58:20-25.

Wells, N. A. 1935a. The influence of temperature upon the respiratory metabolism of the Pacific
killifish, Fundulus parvipinnis. Physiol. Zool., 8:196—227.

. 1935b. Variation in the respiratory metabolism of the Pacific killifish, Fundulus parvipinnis,

due to size, season and continued constant temperature. Physiol. Zool., 8:318—336.

Accepted for Publication 26 June 1997.

Bull. Southern California Acad. Sci.
97(1), 1998, pp. 9-32
© Southern California Academy of Sciences, 1998

Polychaete Fauna from San Quintin Bay, Baja California, Mexico

V. Diaz-Castafeda and V. Rodriguez- Villanueva

Departamento de Ecologia, CICESE,
Apartado Postal 2732, Ensenada, 22800 Baja California, México

Abstract.—Polychaete annelids collected in San Quintin Bay were analyzed. Thir-
ty-nine stations were sampled with a geological type corer in December 1992, in
depths of 2 to 6 m. A total of 677 polychaetes (17 families, 28 genera and 32
species) were recognized. Sixteen species and four genera were recorded for the
first time in the area. The best represented families were: Syllidae (124 speci-
mens), Lumbrineridae (100), Flabelligeridae (75), Nereididae (74), Cossuridae
(73), Spionidae (58), Capitellidae (49), Cirratulidae (44) and Maldanidae (29).
The most abundant species were Scoletoma tetraura, Brada villosa, Cossura can-
dida, Neanthes acuminata, Pionosyllis sp., Notomastus sp., Exogone lourei, Prion-
ospio heterobranchia, Chaetozone sp. and Exogone dispar.

The eastern arm of San Quintin Bay presented slightly higher values of species
richness and polychaete abundances. Of the 28 families previously reported for
this lagoon, 17 were found and the families Trichobranchidae and Apistobran-
chidae are added. To date, there are 81 polychaete species, belonging to 30 fam-
ilies, reported from San Quintin Bay.

Some important lagoons are located on the Pacific coast of México; these are
relatively undisturbed areas, possessing high biodiversity and endemic species,
and are ecologically important for several migrating bird species (Massey and
Palacios 1994). They also present hydrological and sedimentary characteristics
which make them ideal for aquaculture and commercial fishing. It is therefore
important to obtain baseline scientific data before major development takes place.
San Quintin Bay in particular represents a highly productive environment, favored
by regular occurrence of upwellings which provide nutrients (Alvarez-Borrego
and Chee-Barragan 1976; Ibarra-Obando 1990). It has been used for some years
for bivalve aquaculture and its high diversity of marine species also makes it
important for fisheries (Rosales-Casian 1996). An ambitious development project,
sponsored by private interests, involves construction of two golf courses, family
residences, condominiums and hotels along the barrier beach of San Quintin Bay
(Pro esteros 1996). We are studying the polychaete fauna of the San Quintin
lagoon complex (False Bay and San Quintin Bay) before the ecosystem is deeply
disturbed.

The hydrology of San Quintin Bay has been studied extensively (Del Valle-
Lucero and Cabrera-Muro 1981la, b). Overall, due to shallow depths and tidal
currents, there are no significative vertical gradients regarding salinity, tempera-
ture, inorganic phosphates and silicates (Lara-Lara and Alvarez-Borrego 1975).
Generally, water is renewed every 48 hours in the western arm and in a few
weeks in the eastern arm (Lara-Lara et al. 1980; Monreal 1980).

10 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Lara-Lara et al. (1980) concluded that variability at the mouth of San Quintin
Bay during summer was caused by upwelling events, the tidal cycles and the solar
radiation cycle. However, seasonal variability was mainly due to turbulence in-
duced by winds and tidal currents. During spring tides, up to 80% of the bay
water may go out. Usually diatoms and dinoflagellates dominate phytoplankton
assemblages in the bay during summer (Silva-Cota and Alvarez-Borrego 1988).

In contrast, there is a lack of information on San Quintin macrofauna (Barnard
1970). Polychaetes constitute a very important macrofaunal group here because
they comprise around 70% of the infauna biomass and individuals (Calderén-
Aguilera and Jorajuria-Corbo 1986). However, only two polychaete surveys are
found in the literature, one by Reish (1963) who sampled 90 stations in 1960 and
the other by Calderén-Aguilera (1986, 1992) who sampled 11 stations in 1981—
82 (see Table 1). The former dealt only with the eastern arm of the bay while the
latter had only three stations in the western arm (False Bay).

Since the San Quintin lagoon system and southern California belong to the
same biogeographic province (Brusca and Wallerstein 1979) a study of its benthic
communities can be useful both to rebuild initial conditions in the polluted har-
bours of Newport, San Diego and San Pedro (Barnard et al. 1962) and to serve
as a baseline for conditions at San Quintin Bay in the event of future development
(Caldero6n-Aguilera 1992).

Seagrass beds are important nursery areas for many species of fish and inver-
tebrates, including several of economic importance (Stoner and Livingston 1980;
Orth and Montfrans 1990). They also help to stabilize sediments, thus reducing
coastal erosion; sediment stability created by seagrass rhizomes and blades is in
great part responsible for the composition and diversity of the seagrass fauna (Orth
bO7 7:

San Quintin Bay is located on the Pacific coast of Baja California (30°24’—
30°30'N, 115°57'-116°01'W). This lagoon complex has an area of 42 km? and
about 60% of it is covered by the eelgrass Zostera marina. Japanese oysters
Crassostrea gigas have been cultivated since 1980 on a small scale (Ibarra-Ob-
ando 1990); no rivers empty into the bay regularly and most of the houses along
the shoreline have septic tanks, so it can still be considered a relatively undis-
turbed area. Intensive, large-scale oyster mariculture is being considered for the
near future (Ibarra-Obando 1990). The lagoon has the shape of an “Y” with a
single entrance at the base of the Y (Fig. 1). The western arm (False Bay) has
an average depth of 4 m whereas the eastern arm (San Quintin Bay) has an
average depth of 8 m. During low tides around 20% of the seafloor is exposed.
Upwellings have been reported, in spring and summer, south of the common
mouth near Punta Entrada. Granulometric studies show that clay and silty-sand
predominate in shallow areas as well as toward the north within both arms. Very
fine sands are more abundant near the mouth of the system. Channels are essen-
tially located on the eastern side of False Bay, and in both arms also run along
the middle region. The channel sediments are highly diverse, from medium to
fine sand and silt (Barnard 1970; Calderén-Aguilera 1992). The lagoon margins
and especially the northern region of both arms present a typical saltmarsh flora
dominated by Spartina foliosa and Salicornia virginica.

POLYCHAETES FROM SAN QUINTIN BAY

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Materials and Methods

Thirty-nine stations were sampled during 10—11 December 1992, including 13
stations in the western arm and 26 stations in the eastern arm (see Fig. 1). Samples
were collected with a geological corer (16 cm internal diameter, 12 cm depth,
sampling area of 0.02 m’). Temperature and redox potential were measured im-
mediately after collection of each sample by probing 2—3 cm inside the sediments
an electrode coupled to a field potentiometer and a thermometer. Sediments were
sieved in the field using 1.0 mm mesh size and retained material was fixed in 7%

SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

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14 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

buffered formaldehyde. In the laboratory, samples were washed using a 0.5 mm
mesh and transferred to 70% isopropanol. Polychaetes were then sorted and iden-
tified to species level whenever possible.

The systematic arrangement of Fauchald (1977a) for families was followed. For
each species the following information is provided: the material examined including
the total number of specimens collected at each station (station number in brackets);
principal characteristics elaborated by direct observation of collected specimens and
literature; data related to habitat, including data obtained during this survey; geo-
graphic distribution as currently recognized, including new records for the study area.
For each species abundance per station is given, referring to the number of specimens/
0.02 m?. Abbreviations used in this paper are: Eh, redox potential (in mV); D, depth
(in m); T, temperature (in °C); O.M., organic matter (% of dry weight); this last one
was evaluated by ignition loss (Byers et al. 1978).

For approximately 10 species (e.g., L. mexicanus, S. rubra, S. tetraura, C.
candida, P. cirrifera, etc.) our observations differ in some details from published
descriptions, for example concerning the apparition of branchiae, number of tho-
racic setigers, transition thorax-abdomen, appearance of multidentate or suba-
cicular hooks, location of ipsiloid setae, number of neurospines and notospines.
These differences can be due to individual variation within a population and in
some cases also to geographic variation.

Results

A total of 677 polychaetes were collected and identified, belonging to 17 fam-
ilies, 28 genera and 34 taxa: 32 species and two at family level (Table 1). The
families best represented were Syllidae (124 specimens), Lumbrineridae (100),
Flabelligeridae (75), Nereididae (74), Cossuridae (73), Spionidae (58), Capitelli-
dae (49), Cirratulidae (44) and Maldanidae (29). Altogether these families ac-
counted for approximately 90% of the polychaetes collected. The first four fam-
ilies constituted approximately 55% of the total abundance.

The Eh values were negative at most of the stations. In the eastern arm they
varied between —360 mV and +168 mV; False Bay presented values that ranged
from —326 mV to +181 mV. Sediment temperatures ranged between 18.9 and
21.9°C (Table 2).

The most abundant species were Scoletoma tetraura (100 organisms), Brada vil-
losa (75), Cossura candida (73), Neanthes acuminata (72), Pionosyllis sp. (70),
Notomastus sp. (49), Prionospio heterobranchia (34), Exogone lourei (34), Chae-
tozone sp. (28) and Exogone dispar (15) (Table 3). Of the 28 families already reported
for the San Quintin lagoon system, 17 were found in the present work and two
families were added: Trichobranchidae and Apistobranchidae. Of the 32 species col-
lected, approximately 40% had not been previously reported in the system.

Families and Species Collected
Family Orbiniidae Hartman, 1942

Leitoscoloplos mexicanus (Fauchald 1972), illustrated in Mackie 1987: 11, Figs.
10 a-d.

Material examined: 3 specimens: (31) 2; (41) 1.
Characteristics: Incomplete animals with 17 to 21 setigers. Short, pointed pro-
stomium. Peristomium without setae, transition from thorax to abdomen at setigers

POLYCHAETES FROM SAN QUINTIN BAY

eS)

Table 2. Stations location, physico-chemical parameters and granulometry at San Quintin sediments.

O.M.

Station Lat. N. Long. W. Eh(m\V) re (%) Sand (%) Silt (%) Clay (%)
l 235 39.86 30.86 29.28
2 30°29'34” 115°59°34" =255 21.40 0.43 96.80 3.20 0.00
3 1.86 63.78 23.64 7.90
4 30°29'23” WiS°58'57" —184 20.80 b33 60.08 25.81 13.61
5 30°29'06" 115 259,0 12. lea 20.10 2.81 44.97 3022, 22.46
6 30°29'02” iS 5 Susie 103 20.50 2.78 13.42 6552 21-26
a 30°28'38" LIS S8226" S150) 20.50 1.91 63.79 23.38 10.21
8 30°28'45” 1S SS LO” —280 20.40 0.58 71.88 27.84 O77
9 30°28'50” LS S52 One 20.60 2.66 36.20 36.38 DIAG RS

10 30°28'28” PISeS 729% 168 21.40 D237 65.82 18.78 14.63
a 30°28'18” LIS S57 46" —294 20.50 0.79 84.38 1p os | 4.11
12 3027/52! LIS 257 250+ S'S 19.10 0.00 25.84 66.09 8.10
13 30°27'48 MISES TAG! —203 20.50 0.58 86.72 13.28 0.00
14 30°27'49” LES 7230" —320 21.00 L355 50.59 35.64 12.80
15 30°28'02” MIS Sk” 26 19.90 338) 19.77 44.88 27.69
16 B30 2733" LUSSS7T" 4" —360 20.00 3.10 96.68 B32 0.00
7 S027 2)” 5257209" = 2310) 20.40 1.89 545k 5155 14.86
18 30°27 467 115°57'06" —200 20.40 1.40 69.61 6.59 2ST
19 30°26/327 ei Syeo ual ly =D. 21.40 2.03 60.08 25:81 Neon
20 30°26'46” 15257100" — 56 20.10 0.62 74.65 25.04 236
Ds 302652 MS256-37- =i 20.30 0.76 78.61 12.34 9.26
Dp 5027-07” 11S°56717" —30) 18.90 1.68 377 3552 22.97
23 30726133” 115°56'03” 152 19.30 127 42.58 40.04 25.89
24 DIDS) 31.95 28.86 24.06
25 30°26/22” hl S556/337 = 259 20.70 0.89 52.38 24.01 20.78
26 30°25'58”" M1S-56'43" —166 21.60 0.43 97.06 2.90 0.00
if 30225 50” 115°57'09” ps, DAO 1.38 98.08 1.92 0.00
28 3025 12” MIS 5731" a6 20.50 0.48 89.05 10.95 0.00
29 $0°24'327 SSS 7° 29% —242 21.60 0.28 98.13 DDS 0.00
30 30°24'29” 11S°58/387 —94 20.50 0.05 71.78 17.04 8.86
31 30°25'10" iis sts 1 —104 2150 0.37 88.40 11.79 0.00
32 30°24'39” 1S 5946" — laa 20.50 1.99 66.82 21.80 10.39
33 S026 2” 115°59'44” —285 20.60 0.26 93.75 625 0.00
34 3022532” 115°00'14” —84 21.10 2.96 51-30 36.54 1252
35 8072542” 115°59'44” —326 21.10 p4p)\\ 4D 27 45.83 6.40
36 3025152" L559" 127 = LO 2ZARSO 0.53 58.99 33.54 7.03
37 3072621” 115597334 205 20.60 0.93 30.03 60.00 6.05
38 30°26’ 10" 115°59'58”" ll 21.00 DEST 39.00 46.14 SVT
39 30°26'00” 150026" —148 19.80 1.16 7.26 72.59 Sale7

13-14. Branchiae present from setiger 13—14, the first short, thin and triangular;
increasing in size rapidly. Thoracic notopodia with postsetal lobes thin and tri-
angular, increasing in size along the thorax. Abdominal segments without ventral
cirri. Abdominal notopodia with postsetal lobes lanceolated; neuropodia bilobed,
internal lobe long and stronger. All setae similar, long and thin capillaries, each
laterally crenulated and bifurcated.

Observations: Specimens had branchiae from setigers 13—14, not from setigers
11—12 as mentioned in the original diagnosis; they also present 13—14 thoracic
setigers, not only 14 as mentioned in Mackie (1987).

Habitat: In deep waters, 1400 m (Fauchald 1972) and 1377-1417 m (Mackie

16 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

1987). In mud and sandy mud; D = 28.6—106.4; T = 13.2-17.5; O.M. = 1.5—
6.9 (Hernandez-Alcantara 1992). In mud and sandy mud; D = 20-70; T = 24—
30; O.M. = 0.3—1.6 (Gonzalez-Ortiz 1994). In this study, this species appeared
in shallow waters, near the mouth and at the northern region of False Bay (Fig.
1), in sand and muddy-sand; D = 2-5; Eh = —104 to + 100; T = 21.5—21.6;
O.M. = 0.28-—2.57.

Distribution: Salsipuedes Basin, Gulf of California (Fauchald 1972); continental
platform, east coast of the Gulf of California (Hernandez-Alcantara 1992); Ma-
zatlan, Morro and Salina Cruz (Gonzalez-Ortiz 1994).

Scoloplos rubra (Webster 1879; Taylor 1984) 1.29, Figs. 1.28 a-—d.

Material examined: 6 specimens: (31) 3; (29) 1; (15) 1; (18) 1.

Characteristics: Organisms with 160 to 248 setigers. Prostomium conical, point-
ed, larger than its width. Peristomium formed by one asetigerous segment. Simple
branchiae present from setiger 6. Thorax with 19 to 26 setigers. Notopodia with
cirriform lobes from setiger 1; thoracic neuropodia with papillae on the last se-
tigers. Abdominal notopodia cirriform, similar to the branchiae; neuropodia with
short and small presetal lobes. Thoracic notosetae are crenulated capillaries; neu-
rosetae crenulated capillaries, grouped in 4 rows, with one acicular long and
curved hook. Pygidium with four short cirri.

Observations: The specimens from San Quintin possess 19 to 26 thoracic se-
tigers; however Taylor (1984) mentioned 23 to 28 setigers.

Habitat: Intertidal to 200 m (Day 1973; Taylor 1984), in fine sand, silty mud
and sandy mud (Taylor 1984). Mud, sandy mud, muddy sand, sand, sandy gravel,
D = 16.5-54; T = 17-31; O.M. = 0.42-1.25 (Rodriguez-Villanueva 1993; Mi-
randa-Vazquez 1993). In sandy sediments, near the mouth of the bay, north of
Punta Azufre, D = 5; Eh = —104; T = 21.5; O.M. = 0.28.

Distribution: Amphiamerican. Southeastern United States, Gulf of Mexico to
Campeche (Fauchald 1972). Eastern Pacific, between Alaska and Mexico, North
Carolina, Northern Gulf of Mexico (Taylor 1984). Coasts of Tampico, Veracruz
and Campeche, Mexico (Rodriguez- Villanueva 1993; Miranda-Vazquez 1993).

Family Eunicidae Berthold, 1827
Marphysa sanguinea (Montagu 1815; Fauchald 1970) 64—66; 1977b: 42.

Material examined: 2 specimens: (6) 2.

Characteristics: Incomplete organisms up to 47-75 setigers. Bilobed prosto-
mium, peristomium formed by two achete segments, first one double width of the
second. Branchiae begin at setiger 14-19, one filament, with up to 3—4 filaments
at posterior setigers. Black acicula. Subacicular simple hooded hooks present from
setiger 32—35. Neurosetae with pectinate and limbate setae, compound spinigers
from setiger 1.

Observations: Collected specimens had branchiae before setiger 42 and suba-
cicular hooks at setiger 48 as mentioned by Gathof (1984); they also correspond
to Fauchald (1970) who indicated that branchiae begin at setiger 24—35 in juvenile
worms. Pettibone (1963) and Hartman (1944) mentioned variations regarding the
Start of branchiae; they appear from setiger 17 to 57.

Habitat: In shallow water up to 120 m (Pettibone 1963). Intertidal and inter-
Stitial at the west of México (Fauchald 1970); at 65 m in coarse sand (Gathof

POLYCHAETES FROM SAN QUINTIN BAY Ly.

1984); in the eastern arm of San Quintin Bay, near Molino Viejo; in silty clay.
D— 4:-Eh = +103; T = 20.5: OM. = 2.78.

Distribution: English Channel, France, Mediterranean, Adriatic Sea, Massachu-
setts to Florida, Gulf of Mexico, Bermudas, Bahamas, West Indies, Japan, China,
southern California to Mexico, Panama. Indian Ocean, Red Sea, Australia, New
Caledonia, east, west and south Africa (Pettibone 1963; Day 1967). Cosmopolitan
(Fauchald 1970). Pacific, Atlantic and Indian Oceans, Mediterranean Sea and
Japan (Miura 1977). Southern Texas (Gathof 1984). Tecolutla, Veracruz, Mexico
(Moreno-Rivera 1986) and Tamiahua lagoon, Veracruz (Nava-Montes 1989).

Family Lumbrineridae Malmgren, 1867
Scoletoma tetraura (Schmarda 1861) n. comb.

Lumbrineris tetraura (Hilbig 1995) 309-310, plate 11.13, Figs. a—g.

Material examined: 71 specimens: (2) 1; 8 (1); (11) 1; (13) 4; (16) 7; (17) 1;
eo) 8: (31) 13.32) 1; (3) 2; G5) 133 G7) 16; G8), 2:40) kG):

Characteristics: Incomplete organisms with 32 to 220 setigers; complete organ-
isms with 284 setigers. Prostomium rounded anteriorly. Simple hooded hooks
present from setiger 1, with 8—9 distal teeth. The transition between simple hooks
and posterior stouter, short hooks, between parapodia 40—60; one big rostral tooth
and five small apical teeth. Anterior parapodia with truncate presetal lobes, in
posterior parapodia double length of the presetal ones. Maxillary formula, I: 1,
Met4—5, WT: 2, IV: 1.

Observations: Simple hooks with 5 to 8 distal teeth and not 8-9 as mentioned
by Hilbig (1995). The transition of the hooks take place at setigers 17—46, this
rank is different from that reported by Hilbig (1995).

Habitat: Intertidal (Fauchald 1970) to 60 m; off the coast of Zaire (ex Congo)
it has been registered at 3806 m depth (Miura 1980). Flexible with regard to
substratum; it has been reported from mud, sand and silty sand, D = 20-76; T
= 21-30; O.M. = 0.17—1.67 (Gonzalez-Ortiz 1994). In the present study the
species was collected frequently from both arms of the bay. In sand, sandy-mud
and muddy-sand, D = 1—-5;.Eh = —360 to + 100; T = 20-—21.6; O.M. = 0.05-—
See

Distribution: Africa and widespread in the Americas (Fauchald 1970); Califor-
nia, Peru, Chile, Argentina (Miura 1980). In the Mexican Pacific it has been
registered in the east coast of the Gulf of California (Fauchald 1970; Kudenov
1973; 1975; 1980; van der Heiden & Hendrickx 1982; Arias-Gonzalez 1984;
Hernandez-Alcantara 1992).

Family Cossuridae Day, 1963
Cossura candida (Hartman 1955, Hilbig 1996) 394-396, Figs. 9.4 a—g.

Material examined: 36 specimens: (13) 1; (16) 8; (26) 14; (27) 8; (33) 1; (35)
G7): 3.

Characteristics: Incomplete organisms with 20 to 65 setigers. Prostomium con-
ical, rounded, with two peristomial segments of the same length. Tentacle inserted
in setiger 3. Setae of two different types: short, coarse setae with relatively short,
stiff hairs along the cutting edge located anteriorly; longer setae with a dense
border of fine hairs.

SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

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20 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Observations: In the studied organisms the transition from thorax to abdomen
took place at setiger 25—30; different from the setigers reported by Hilbig (1996):24.

Habitat: In shelf, on the continental slope and basin depths (Fauchald 1972).
11 to 2400 m; sand and sand mixed with silt-clay (Hilbig 1996). This species
was collected in shallow waters, in both arms of the bay, in sandy-mud and
muddy-sand, D = 1-4; Eh = —360 to —160; T = 20-22; O.M. = 0.05-3.00.

Distribution: Southern California, Cedros Island, Acapulco, Zihuatanejo, in the
Central American Trench (Fauchald 1972). México, Baja California; southern and
central California (Hilbig 1996).

Family Spionidae Grube, 1850
Prionospio heterobranchia Moore, 1907

Prionospio (heterobranchia) newportensis (Reish 1959) 13—1960:94. (Hartman
1969) 157, Fig. 1.

Material examined: 22 Specimens: (12) 2: (13) 2: (16) 8; C26) 2: _@7) 2268
1 G2) 1G3) 33-67) 2.

Characteristics: Incomplete organisms with 24 to 46 setigers. Rounded prosto-
mium, slightly truncated. Two pairs of black eyes, anterior pair smaller, rounded
and farther apart. The caruncule extends to setiger 2, without median antenna.
Five pairs of branchiae from setiger 2; pairs 1, 4, 5 pinnate and 2, 3 cirriform.
Capillary notosetae limbate, larger in the setigers with branchiae, becoming small-
er posteriorly; hooded hooks from setiger 36.

Habitat: Intertidal in sand and mud (Calder6n-Aguilera & Jorajuria-corbo
1986). Found in both arms of San Quintin Bay in sand, sandy-mud and muddy-
sand, D = 2-5; Eh = —360 to —104; T = 20-—21.6; O.M. = 0.05-—3.00.

Distribution: California (Macioleck 1985). From Newport, California to Pana-
ma (Calder6n-Aguilera & Jorajuria-corbo 1986). In the Mexican Pacific: Bahia
de Mazatlan, Sinaloa (Arias-Gonzalez 1984), Bahia Concepci6én, Baja California
Sur (Salazar-Vallejo 1985), Isla Tiburén, Punta Arboleda, Sonora and Isla Maria
Madre, Nayarit (Hernandez-Alcantara 1992).

Prionospio (Minuspio) cirrifera (Wirén 1883; Macioleck 1985) 352-355, Fig.
10 a—-g

Material examined: 1 specimen: 13 (1).

Characteristics: Specimen with 23 setigers. Prostomium large and rounded,
elongated posteriorly until setiger 2; two pairs of eyes in trapezoidal arrangement.
Peristomium with lateral wings moderately developed, not overlaping the prosto-
mium. Eight pairs of branchiae, all cirriform, anterior ones larger than posterior
ones; not joined to the notopodial lobe. Multidentate hooded hooks present from
neuropodia 13-18 and at the notopodia after setiger 26.

Observations: In the studied organism the multidentate hooded hooks were
present from neuropodia 19, however the reported rank by Light (1978) goes
from 13-18.

Habitat: Preference for silt and sandy silt, also found on sand and silty sand.
Predominantly muddy bottoms, silty mud, off jeties, intertidal rock pools, sand.
Eurybathyal, intertidal to 2500 m (Foster 1971; Light 1978). In marine and es-
tuarine environments, from the intertidal to great depths (Calderén-Aguilera &
Jorajuria-corbo 1986). From 11 to 2900 m (Maciolek 1985). Mud and sandy-mud,

POLYCHAETES FROM SAN QUINTIN BAY 21

D = 30-150; T = 27-28; O.M. = 0.8—-1.65 (Rodriguez-Villanueva 1993; Mi-
randa-Vazquez 1993). Collected only in the eastern arm, near Muelle Viejo, in
sandy-mud, D = 5; Eh = —203; T = 20.5; O.M. = 0.80.

Distribution: Arctic; Atlantic from Greenland to South America; North Sea and
English Channel; Bering Sea to Gulf of California; Queensland, New South Wales
and Victoria in Australia (Light 1978; Calder6én-Aguilera & Jorajuria-corbo 1986).

Prionospio (Minuspio) multibranchiata (Berkeley 1927; Macioleck 1985) 365—
367, Figs. 15 a-e.

Material examined: (7 specimens): (12) 2; (15) 5.

Characteristics: Prostomium rounded, widest at level of eyes. Peristomium
fused to setiger 1. Caruncule extending to 1-2 setiger. 4 eyes. Long cirriform
branchiae from setiger 2, 7—9 pairs; first branchiae longer. Notopodial lamellae
absent in first setiger, in the others well developed. All anterior setae capillary.
Hooded hooks from setigers 12—18, in neuropodia from setigers 25—32. Sabre
setae from neuropodia 12-16.

Habitat: Intertidal (Maciolek 1985). In muddy sand, D = 104 m; T = 14.2; S
= 35.26; O.M. = 7.2; DO = 2.40 ml/l (Hernandez-Alcantara 1992). This species
was collected only in the middle region of the eastern arm, in silty-clay sediments;
D = 4; Eh = —126 to —145; T = 19.1-19.9; O.M. = 3.33.

Distribution: Vancouver Island, Canada; Washington, Florida, northern Gulf of
Mexico (Macioleck 1985). Concepci6n River, Sonora (Hernandez-Alcantara
1992).

Polydora socialis (Schmarda 1861)
Polydora plena. Foster, 1971: 24—25, Figs. 22-29.

Material examined: (7 specimens): (22) 1; (28) 1; (29) 5.

Characteristics: Prostomium bilobed, with 4 eyes. Caruncule extending to se-
tiger 4—8. Palps missing. Anterior setae all capillaries. Setiger 1 with notosetae;
setiger 5 large, twice the size of preceding segments, with modified rounded
hooks. Neuropodial bidentate hooks without manubrium from setiger 7, apical
tooth diminishing in size in posterior segments. Branchiae from setiger 7—8 as
small digitiform lobes, progressively increasing in size. Dorsal lamellae digiti-
form. Pygidium with one large ventral lobe fused with two smaller dorsal ones.

Observations: Hernandez-Alcantara (1992) found cirriform branchiae from se-
tiger 8 and caruncule extending to setigers 4—9, we observed branchiae from
Setigers 7-8 as Light (1978) and caruncule up to setiger 7.

_Habitat: Intertidal to 70 m depth (Day 1973; Salazar-Vallejo 1981). In mud and
silt, in lagoons (Hartman 1969). Forms silt tubes in a variety of substrates, pri-
marily sandy silt (Reish 1968); also boring in living and dead shells (Johnson
1984). In sediments often forming large beds (Light 1978). This species was
collected from middle area of eastern arm, as well as near the sea entrance, in
sediments sand-silt; D = 2—3; Eh = —30 to —242; T = 18.9-21.6; O.M. = 0.3-—
1.68.

Distribution: Cosmopolitan. California to Chile; North Carolina and Gulf of
Mexico (Day 1973); San Francisco Bay south to Oceanside (Hartman 1969). East
and west coasts of North America, Falkland Islands (Johnson 1984). New South

pe SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Wales, Victoria, New Zealand, North and South America (Blake & Kudenov
1978).

Spio pettiboneae (Foster 1971; Johnson 1984) 6-63, 6-65, Figs. 6-54 a-e.

Material examined: 9 specimens: (4) 1; (13) 1; (30) 3; (32) 4.

Characteristics: Incomplete organisms with 18 to 41 setigers. Head and anterior
segments with brown pigment pattern. Prostomium anteriorly inflated, rounded,
with caruncule. Two pairs of eyes, anterior pair larger and farther apart. Well
developed peristomium, nucal organs extending on to setiger 3. Branchiae present,
those on setiger | smaller than those on the following setigers. Anterior setae uni-
or bilimbate, arranged in two rows. Ventral sabre setae. Tridentate hooded hooks
first replacing posterior row of capillary neurosetae on setiger 11-15.

Observations: Hooded hooks began at neuropodia 11—13; Johnson (1984) re-
ported they begin at 11-15.

Habitat: Intertidal to 120 m. Predominately in fine and medium sand; also in
silty sand (Johnson 1984). In sand and sandy-mud, D = 28—46; T = 27-28; O.M.
= 0.21-1.0 (Rodriguez-Villanueva 1993). This spionid species was collected in
the head and the middle area of San Quintin arm and at the mouth of the bay, in
sandy and sandy-mud sediments, D = 1—5; Eh = —203 to —94; T = 20.5—21.5;
O.M. = 0.43-1.40.

Distribution: North Carolina and Gulf of México (Foster 1971; Day 1973; John-
son 1984), western Baja California, Mexico.

Family Cirratulidae Carus, 1863
Monticellina tesselata (Hartman 1960; Blake 1996) 328-330, Figs. 8.27 a-f.

Material examined: 9 specimens: (13) 4; (17) 2; (27) 1; (33) 2.

Characteristics: Incomplete organisms with up to 42—63 setigers. Conical pro-
stomium, rounded apically, without eyes. Long peristomium, no rings were ob-
served. One pair of palps inserted dorsoventrally. Branchiae from the first setiger;
inserted above the notopodial base. Notosetae long and slender, forming tufts in
anterior and middle regions. Neurosetae shorter and fewer; those in posterior
segments geniculate, with serrated edges.

Observations: In the studied specimens the location of the tentacular palps was
not clearly observed perhaps partly due to the bad state of the material; Blake
(1996) said they insert at the posterior margin of the peristomium. The dorsal
ridge along the thoracic region was not observed, but its presence is only men-
tioned by Blake (1996). Hartman (1969) does not mention it.

Habitat: On shelf and slope depths, from shallow water to great depths. In silty
and muddy sediments (Hartman 1969; Blake 1996). In sand and muddy sand, D
= 39-72; T = 21-30; O.M. = 11-0.94 (Gonzalez-Ortiz 1994). Eastern arm and
near the mouth of San Quintin system, in sandy-mud and muddy-sand, D = 2-—
5; Eh = —285 to —200; T = 20.4—21.1; O.M. = 0.5-3.33.

Distribution: Southern California (Hartman 1968) to western Mexico: Conti-
nental shelf of the Gulf of California (Reish 1968; Van Der Heiden & Hendrickx
1982; Arias-Gonzdlez 1984; Lezcano-Bustamante 1989; Hernandez-Alcantara
1992) and Gulf of Tehuantepec (Gonzdalez-Ortiz 1994); central and southern Cal-
ifornia (Blake 1996).

POLYCHAETES FROM SAN QUINTIN BAY 23

Cirriformia spirabrancha (Moore 1904; Blake 1996) 361—363, Figs. 8.42 a-f.

Material examined: 7 specimens: (8) 5; (14) 1; (35) 1.

Characteristics: Incomplete organisms with 82—96 setigers, complete worms
with 118—152 setigers. Rounded prostomium, without eyes. Long peristomium
with 3 segments forming a protuberance which extends up to setiger 5, where
both tuffs of tentacular filaments are already observed. Branchiae appear at setiger
5. Neuroacicular spines from around setigers 40—45, in the first 3—5 per fascicule,
increasing to 5—6 from setigers 100 to 150; notoacicular spines beginning pos-
terior to setiger 60—70.

Observations: In the observed specimens neurospines begin at setigers 17—23
and notospines at setigers 26—40; in the first fascicles there are one or two spines,
posteriorly we acknowledged 4—5 per fascicule, not in the number and order
mentioned by Blake (1996). He also said that Cirriformia spirabrancha has been
confused with Cirriformia moorei due to reports of the last species in muddy
sediments, in estuaries and associated with Zostera marina as opposed to C. spir-
abrancha, which has only been reported in hard substrates (rocks, gravel at ex-
posed beaches).

Habitat: Inhabits tide pools in the rocky intertidal on semi-exposed shores. In
crevices and under rocks (Blake 1996). Our specimens were collected principally
at sandy mud with some shell fragments, middle region of western and eastern
arm, D = 2-5; Eh = —280 to —326; T = 20.4—21.1; O.M. = 0.58-2.21.

Distribution: Northern, central and southern California (Blake 1996).

Family Maldanidae Malmgren, 1867
Clymenura gracilis (Hartman 1969):439, Figs. 1—4.

Material examined: 5 specimens: (13) 1, (6) 1, (38) 3.

Characteristics: Organisms with 10—13 setigers. Cephalic plaque with smooth,
wide flange almost all around. Long nuchal organs, extend through *% of cephalic
plaque. Without eyes. Buccal segment as long as first and second setigers, fol-
lowed by 5 shorter segments, setigers 9 to 13 longest. First setiger with few uncini
increasing to 6 in a row in second setiger. Setigers 7 and 8 with glandular bands.

Habitat: In shelf and canyon depths, in silty mud and green sand. Constructs a
friable tube of silt and gravel (Hartman 1969). In San Quintin at 3—5 m depth, in
the middle area of both lagoon arms, in sandy mud and muddy sand. D = 3-5
m; Eh = —203 to +103; T = 20-21; O.M. = 0.6—2.6.

Distribution: Southern California (Hartman 1969). San Quintin lagoon, Baja
California.

Family Syllidae Grube, 1850

Exogone dispar (Webster 1879; Uebelacker & Johnson 1984) 30—42, 30—43, Fig.
30-36 a-e.

Material examined: 15 specimens: (13) 1; (32) 1; (37) 9; (39) 4.

Characteristics: Incomplete organisms with 44—48 setigers. Rectangular prosto-
mium with two pairs of eyes in trapezoidal arrangement. Pharynx extends to
setigers 3—5, with a subterminal tooth. Extended proventriculus up to setigers 3
to 6 or 4 to 7. Antenna rising from anterior part of prostomium, median antenna
fusiform, short palps, lateral antenna small and digitiform. Palps completely fused

24 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

dorsally. Dorsal and ventral tentacular cirri digitiform; dorsal cirri present in all
setigers. Compound setae with 1—2 superior spinigers per fascicle and one small
bidentate seta. Compound falcigers, all distally bidentate with primary tooth ter-
minal. Simple ventral setae bidentate.

Habitat: Intertidal to 130m (Day 1973). From shallow waters to 5023 m; in
sandy shell, sand and corals (Uebelacker & Johnson 1984). Middle area of eastern
arm and western arm; in sand and sandy-mud, D = 1-5; Eh = —326 to —174;
T = 19.8-20.6; O.M. = 0.53-—2.96.

Distribution: Arctic, North Pacific, North Atlantic, Maine to Florida, Gulf of
Mexico; Alaska to the Pacific coast of Mexico, Galapagos; South Japan and south-
ern Africa (Day 1973; Uebelacker & Johnson 1984).

Exogone lourei (Berkeley & Berkeley 1938; Kudenov & Harris 1995) 15-17, Fig.
1.3 a-f.

Material examined: 2 specimens: (16) 1; (35) 1.

Characteristics: One complete polychaete with 43 setigers, one incomplete with
25 setigers. Cylindrical body. Prostomium wider than long; two pairs of eyes,
anterior pair largest, arranged trapezoidally. Antennae located in front of anterior
pair of eyes. Medium antenna fusiform, twice as long as paired lateral antennae,
with a distal papillae. Palps long and fused. Proventriculus cylindrical, shorter
than pharynx. Parapodia with compound spinigers, falcigers and simple setae.
Compound falcigers distally bidentate; secondary tooth larger than primary. Ven-
tral setae curved and distally bidentate. Dorsal and ventral cirri digitiform; dorsal
cirri on all setigers. Natatory setae present from setiger 17. Pygidium with a pair
of cirriform anal cirri.

Habitat: Lower intertidal to 40 m. Calcareous crusts, silty sand, coarse black
sand, gravel with mud; mud. In the middle area of both arms of San Quintin
system, in sandy-mud, D = 4-5; Eh = —360 to —320; T = 20-22; O.M. =
0.79-1.99.

Distribution: Spain. Atlantic: Gulf of Mexico, Belize, Cuba, Canary Islands;
Pacific: south of British Columbia to southern California (Nufiez et al. 1992);
Maria Madre island, Nayarit (G6ngora-Garza 1984). Washington, Oregon, Cali-
fornia, Gulf of Mexico: Texas, Louisiana, Mississippi, Alabama, Florida; Cuba;
Spain (Kudenov & Harris 1995).

Syllis (Syllis) gracilis (Grube 1850; Gardiner 1976) 139, Fig. 12 I-n.

Material examined: 4 specimens: (6) 4.

Characteristics: Complete specimens with up to 73 setigers, incomplete organ-
isms with 37—63 setigers. Prostomium rounded with four small eyes; one median
antenna with 7—22 articles and two lateral antenna with 7—12 articles. Proventricle
extending two setigers. Triangular palps; dorsal and ventral tentaculat cirri artic-
ulated. Ypsiloid setae between setigers 17—20. Pygidium with a pair of articulated
anal cirri.

Observations: Studied specimens presented ypsiloid setae between setigers 17
and 20, whereas Uebelacker (1984) mentioned they are present between setigers
14 and 21.

Habitat: Shallow water to 235 m; among ascidians, algae, serpulid tubes, rocks,
barnacles, oysters, hydroids, broken shells; on pillings. Coarse to fine-very fine

POLYCHAETES FROM SAN QUINTIN BAY 25

sand, silty fine to very fine sand (Uebelacker & Johnson 1984). In the eastern
arm, near Molino Viejo; silty clay, D = 3; Eh = +103; T = 20.5; O.M. = 2.80.
Distribution: Cosmopolitan in temperate and tropical seas (Uebelacker 1984).

Family Nereididae Johnston, 1845
Neanthes acuminata (Ehlers 1868; Taylor 1984) 31-15, Fig. 31-14 a-e.

Material Examined: 26 specimens: (8) 1; (13) 4; (16) 7; (19) 4; (26) 2727) 7;
Gr): I.

Characteristics: Organisms 27 to 42 setigers. Prostomium short, wide posteri-
orly. Tentacular cirri short. Oral ring of pharynx completely encircled by five or
more rings of paragnaths. Group I = a line of four points or 8—12 in oval group,
II = a wedge shaped group, III = an oval group of about 20, IV = a triangular
group of about 20, V, VI, VII and VIII form a complete band of several irregular
rows of roughly equal points. Parapodia similar in all body regions. Notopodia
with well developed pre- and post-setal lobes. Neuropodia with longer presetal
and shorter postsetal lobes. Neurosetae include homogomph spinigers and hetero-
gomph falcigers.

Habitat: Littoral zone to 100 m. Occurs in fine to coarse sediments, often
associated with vegetation (Day 1973; Taylor 1984). In mud, sand and silty clay
(Fauvel 1923). Species frequently found along the middle area of the eastern arm,
in sand, sandy-mud and muddy sand, D = 1.5—5; Eh = —360 to —100; T = 20-
21.6; O.M. = 0.28—2.78.

Distribution: Cosmopolitan in temperate and tropical seas. North Atlantic (En-
glish Channel to Santander); Massachusetts to Florida; Mediterranean (France,
Italy, Monaco); Southern California to Mexico; Tasmania and New Zealand (Day
1973; Taylor 1984).

Family Goniadidae Kinberg, 1866
Goniada maculata (Orsted 1843; Hilbig 1994) 226—228, Figs. 7.5 a-l.

Material examined: 2 specimens: (30) 1; (31) 1.

Characteristics: Organisms with 116 and 128 setigers. Body slender, prosto-
mium conical with up to 10 short rings, four biarticulate antennae. Eyes absent.
Short proboscis; terminal jaws surrounded by 18 papillae; chevrons numbering 8
to 9 on each side, largest pieces in the middle of the group. Parapodia about twice
as long as body width in posterior part of the body; uniramous through setiger
23 to 37. Notopodia with digitiform presetal lobe. Dorsal and ventral cirri digi-
tiform and of subequal length. In anterior parapodia few falcigers; notosetae short,
serrated capillaries; neurosetae compound spinigers and falcigers present in an-
terior parapodia.

Observations: The studied polychaetes presented 9 chevrons on each side, and
were uniramous through setigers 35—38. Hilbig (1994) also mentioned uniramous
through setigers 23 to 37.

Habitat: Intertidal to 3000 m. Occurs in silt, sand and shelly sand (Gardiner
1976; Hilbig 1994). In sandy mud and muddy sand by D = 25—40; T = 28-31;
O.M. = 0.40-0.60 (Gonzalez-Ortiz 1994). South region of San Quintin arm, in
sand, D = 4; Eh = —94 a —104; T = 20-22; O.M. = 0.40-0.50.

Distribution: Cosmopolitan (Gardiner 1976). Arctic Ocean: Greenland, Davis

26 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Strait; Atlantic Ocean: western Europe and Gulf of St. Lawrence, and U.S. coast
to North Carolina; Pacific Ocean: Alaska to California and Japan, Gulf of Iran,
Arabian Sea, Iran coast and South Africa (Hilbig 1994), and Gulf of Tehuantepec
(Gonzalez-Ortiz 1994).

Family Onuphidae Kinberg, 1865
Kinbergonuphis microcephala (Hartman 1944; Fauchald 1982) 24, Fig. 5a.

Material examined: 1 specimen: (27) 1.

Characteristics: Specimen with 36 setigers. Outer lateral antennae reaching se-
tiger 2, inner lateral antennae reach about setiger 7 and median antenna reaches
setiger 4. Ceratophores have four rings. No eyes were observed. Branchiae are
first present from setiger 6; maximum number of branchial filaments is seven;
branchiae absent on the second half of the body. Ventral cirriform cirri present
in the first 2 setigers; postsetal lobes digitiform in first 10 setigers, tridentate
compound hooks in the first 3 setigers, large hooks are present from setiger 5 to
22. Compound spinigers absent. Subacicular hooks present from setiger 23. Each
pectinate setae posses about 10 teeth. The maxillary formula is 1 + 1,9 + 8,9
Tas Oro ange ltoele

Observations: Our specimens differ from K. microcephala in that subacicular
hooks begin at setiger 23 not at 26 and the large hooks appear from setiger 5 to
22. No eyes were observed; outer lateral antenna reach setiger 2, inner lateral
antenna reach about setiger 6 and median antenna reaches setiger 4.

Habitat: In intertidal sands (Fauchald 1968). Collected in the south half of San
Quintin arm, in mud and sand, D = 4; Eh = —220; T = 21; O.M. = 2.23.

Distribution: Gulf of California (Fauchald 1982) and San Quintin system, Baja
California.

Family Oenonidae Kinberg, 1865

Arabella iricolor (Montagu 1804; Uebelacker & Johnson 1984) 42-5, Figs. 42-
2 a-f.
Arabella (Arabella) iricolor. Hilbig, 1995:320-—321, Figs. 12.1 a—g.

Material examined: 3 specimens: (8) 1, (13) 1, (38) 1.

Characteristics: Incomplete organisms with 86 to 146 setigers, complete ani-
mals with 198 to 213 setigers. Elongated, cylindrical body; iridescent, brown or
light yellow. Conical prostomium, longer than wider, without antenna or palpes.
No eyes. Peristomium with two rings, the same size as other setigers. Parapodia
with short dorsal cirri and without acicular spines. Aciculae distally spotted. Man-
dibles dark brown or black with light points. MI = 1 + 1, short, falcated with
6—7 basal teeth; MII = 10-11 + 10—12 asymmetrical, right largest; MII] to MV
symmetrical, MIII = 6 + 6 rounded, bearing 5 small teeth and 1 bigger; MIV =
4+ 4; MV = 1 + 1 single, long pointed tooth arising from small base. Maxillary
support long and large in the superior part, branches slightly separated.

Observations: Our specimens had no eyes, organisms described by Hilbig
(1995) had four subequal eyes in a strait line along the posterior margin of the
prostomium.

Habitat: Intertidal to 85 m; among shells, oysters, among Zostera holdfasts,
bryozoans and algae. In mud, sand, muddy sand and sandy gravel (Uebelacker

POLYCHAETES FROM SAN QUINTIN BAY 4 |

eevones: 1984)..Infine sand; D= 22.2=-1012T = 13:52=16:,6:=934.8235:5330M.
= 2.4—5.7 (Hernandez-Alcantara 1992). In muddy sand, D = 22.2—101, T = 17.3—
27.2; O.M. = 0.12—5.7 (Gonzalez-Ortiz 1994). Intertidal to 90 m. Burrows deeply
into mud, sand and gravel; it is also found under rocks; in oyster and mussel
beds, among bryozoans and other colonial animals (Hilbig 1995). Middle region
of both arms of San Quintin system, in muddy sand, D= 1-5; Eh = —280 to
—110; T= 20.4-—21; O.M. = 0.79-2.78.

Distribution: France, England, Mediterranean Sea, Massachusetts to Florida,
western Mexico (Fauchald 1970). Cosmopolitan in temperate and subtropical wa-
ters (Uebelacker & Johnson 1984). Baja California (Reish 1963; Fauchald 1970;
Rioja 1947, 1962; Salazar-Vallejo 1985; Herndndez-Alcantara 1992); Sinaloa
(Rioja 1962; Fauchald 1970; Hernandez-Alcantara 1992). Gulf of Mexico, Co-
lombia and Venezuela; Vancouver Island to California; Mexico, Argentina; Japan,
China, Persian Gulf, Red Sea, Indian Ocean; Strait of Magellan; West and South
Africa (Hilbig 1995).

Family Flabelligeridae Saint-Joseph, 1894
Brada villosa (Rathke 1843; Milligan 1984) 47-13, 47-15; Figs. 47-10 a—d.

Material examined: 26 specimens: (8) 3; (11) 4; (17) 15; G3) 2; (41) 2.

Characteristics: Incomplete animals with up to 26—93 setigers. Body cylindrical,
slightly flattened ventrally. Dorsal surface encrusted with sand grains. Papillae
cirriform densely distributed. Ventral papillae similar in shape but shorter and less
dense. Filiform branchiae arranged in two lateral groups. Eyes absent. All setae
simple capillaries, crossbared; those from setiger 1 longer, projecting forward
forming the cephalic cage which is weakly developed. Neurosetae slightly shorter
and stouter than notosetae. Conical nephridial papillae present ventrally.

Habitat: From shallow waters to 2000 m. Occurs in mud, gravel, sand, silty
sand, clayey silt and rocks (Milligan 1984). In silty sand, D + 37.2; T = 15.1;
S = 35.5; O.M. = 7.2 (Hernandez-Alcantara 1992). Occurred in both arms of the
bay, in sandy mud and muddy sand, D = 1-5; Eh = —285 to +110; T = 20.4-
21.6; O.M. = 0.05-3.33.

Distribution: Cosmopolitan (Milligan 1984). Northern Gulf of California (Her-
nandez-Alcantara & Solis-Weiss 1993).

Family Sabellidae Malmgren, 1867

Megalomma bioculatum (Ehlers 1887; Uebelacker & Johnson 1984) 54-27, 54-
30, Figs. 54-22 a-g.

Material examined: 5 specimens: (13) 1; (39) 3; (41) 1.

Characteristics: Incomplete organisms 25—27 setigers. Collar bilobated, dorsal
edges rounded and well separated; ventral edges prolonged as two triangular
lobes. Radioles numbering 6—15 pairs, with 1—2 transverse brown bands. Dorsal-
most pair of radioles bearing two subterminal, large rounded eyes. Palps long,
triangular, brown. Thorax with eight setigers. Thoracic notopodia with numerous
slender limbate setae; thoracic neuropodia with an anterior row of companion
setae and a posterior row of avicular uncini with long handles and crest of small
teeth. Abdominal notopodia with avicular uncini with short handles and neuro-
podia with limbate setae.

28 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Habitat: In depth of 10—200 m. In sand, silt and clay (Uebelacker 1984); 90—
200 m (Perkins 1984); sandy mud, muddy sand, gravel and sandy gravel (Ueb-
elacker & Johnson 1984). Found south to Muelle viejo in San Quintin arm and
near the head of False Bay, in sandy mud and muddy sand, D = 1—6; Eh = —200
to +110; T = 19.8-21.8; O.M. = 0.53—2.57.

Distribution: Veracruz (Rioja 1946). Gulf of Mexico, Florida, North Carolina.
Tropical western Africa (Uebelacker & Johnson 1984).

Discussion

Of the 677 annelids collected, 16 new records of polychaete species and 4
records of new genera for the San Quintin lagoon system were found: Leitoscol-
oplos mexicanus, Scoloplos rubra, Scoletoma tetraura, Monticellina tesselata, Ex-
ogone dispar, Exogone lourei, Goniada maculata, Clymenura gracilis, Brada vil-
losa, Prionospio multibranchiata, Spio pettiboneae, Polydora socialis, Cirrifor-
mia cf spirabrancha, Syllis (Syllis) gracilis, Lysidice ninetta, Marphysa sanguinea,
Praxillela sp., Apistobranchus sp., Pionosyllis sp., Euchone sp., and one uniden-
tified species from the family Trichobranchidae. This last family together with
Apistobranchidae are reported for the first time from San Quintin; unfortunately
the organisms were damaged and could not be identified to species level.

Of the 28 polychaete families previously reported for San Quintin, 17 were
found in the present study and two were added. Of the 32 identified taxa, only
twelve had been previously reported in the lagoon system (Reish 1963; Calder6én-
Aguilera & Jorajuria-Corbo 1986). Until now 30 families and 81 species of poly-
chaetes have been recorded in the area (Table 1).

The differences among the three studies at San Quintin may indicate anthro-
pogenic modifications and/or environmental changes which may have affected the
lagoon system over the last 30 years. Nevertheless, they may also be due to
insufficient sampling effort. The first reported sampling took place in the eastern
arm (Reish 1963) and only one other sampling is reported in the literature, with
a reduced number of stations (Calder6én-Aguilera & Jorajuria-Corbo 1986). Con-
sidering the previous study of the area it may be that the new records reported
here are due to a more balanced sampling effort in both arms of the lagoon system.
However, it is possible that the previous authors found more species because they
used a 0.5 mm mesh which allowed them to retain young worms and smaller
species.

Most species presented densities of 1-10 individuals/0.02 m7’, nevertheless five
species corresponded to the class of 71—100 individuals/sample (3500—5000 ind./
m7’): Scoletoma tetraura, Brada villosa, Cossura candida, Neanthes acuminata,
and Pionosyllis sp., these are consistent with an extremely rich fauna. When
species richness per station was plotted we found that two stations (12 and 13),
located in the middle region of the eastern arm presented the highest species
richness with 12 and 14 species respectively. Nine stations showed intermediate
values (6 to 8 species/station), whereas the 19 remaining stations presented low
species richness values going from 1 to 5 species per station.

Conditions in the western arm might favor the development of the more sen-
sitive species, those which cannot tolerate low oxygen concentrations, because
here water is exchanged with the sea at a higher rate. In this study most of the
species were found in fine-grain sediments, predominantly muddy sand and sandy

POLYCHAETES FROM SAN QUINTIN BAY 29

mud, with moderately negative Eh values. Only three stations presented positive
Eh values (station 6, 103 mV, station 10, 168 mV and station 23, 152 mV). Only
four stations (8, 12, 37, 38) were located in the edges of Zostera beds so we can
not say much about polychaete composition in this habitat.

In conclusion there is still a lot of work to be done in San Quintin Bay. Not
only listing the species inhabiting the area but also analyzing their structure and
organization. The fact that we found 20 taxa and two families not previously
reported in this area is probably due to anthropogenic modifications in the last
years. Nevertheless, after examining these results it is evident that there is a need
for extensive research in the coastal lagoons of Baja California in order to ac-
knowledge their biodiversity and also for the local authorities to adequately man-
age their resources.

Acknowledgements

We would like to thank Ignacio Romero, Julio Villaescusa, Victor Martinez
Magana and Dr. Efrain Gutiérrez for their help during field work and Rosa Ji-
ménez for sorting the macrofauna. We are grateful to M. S. Pablo Hernandez-
Alcantara, M. S. Ricardo Martinez-Lara and especially to M. S. Sergio Salazar-
Vallejo for reviewing the manuscript and offering valuable comments.

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Accepted for publication 19 March 1997.

Bull. Southern California Acad. Sci.
97(1), 1998, pp. 33-38
© Southern California Academy of Sciences, 1998

Cetaceans of Isla De Guadalupe, Baja California, Mexico

Juan-Pablo Gallo-Reynoso' and Ana-Luisa Figueroa-Carranza?

'Centro de Investigacion en Alimentacion y Desarrollo,
Unidad Guaymas. Apdo. Postal 284, Guaymas, Sonora 85480, México
*Reserva Islas del Golfo de California, Instituto Nacional de Ecologia,
SEMARNAP. Miramar 210, Col. Miramar, Guaymas, Sonora 85450,

México

Isla de Guadalupe (29°00'N, 118°15’30"W) is located 240 km west of Baja
California, México. The island lies within the California Current, with an average
sea surface temperature of 18°C (range: 16°C spring, 20°C summer; Lynn and
Simpson 1987). Northwesterly winds predominate (Berdegué 1957). The orien-
tation of the island and its elongated shape (35 km long and 6.5—9.5 km wide)
acts as a barrier against the flow of the current which produces a series of swirls
at different depths. The island is surrounded by depths of 3600 m or more. The
island does not have a shelf around it with exception of the southern tip were a
4 km wide and 200 m deep shelf is found between Isla Guadalupe, Isla Zapato
and Isla Toro. The coastline and nearshore physiography is composed of loose
basaltic rocks and boulders bounded by towering cliffs (Pierson 1987).

The only report of cetaceans near Isla de Guadalupe is by Fleischer (1978),
who reported two minke whales (Balaenoptera acutorostrata) 500 m offshore and
bottlenose dolphins (Tursiops sp.) on several occasions. Other reports on marine
mammals in the area exist (i.e. Mangels and Gerrodette 1994), but they are far
offshore from the island.

Our study was carried out while studying Guadalupe fur seals, Arctocephalus
townsendi, during 1991-1993. We made observations during winter (February
1991-1992), spring (June 1983 and 1991), summer (July—August 1991, 1992 and
1993) and fall (November—December 1991 and 1992), during a total of 189 days.
Nearly all of our survey time (179 days) was on the east side of the island.

Observations of cetaceans were conducted: a) from the camp, located at ‘‘Cor-
ralitos’’, on the southeastern coast of the island (28°53’30"N), 30 m above sea
level. Daily observations started at 0600 hr and ended at 2000 h; b) from the
catwalk of Mexican Navy Coastguard boats (approx. 10 m above sea level) during
the approach to or while leaving the island, and c) while conducting censuses of
Guadalupe fur seals in the eastern side of the island (except in summer censuses,
when the entire island was covered). These censuses were conducted in a 5—7 m
fiberglass skiff with an observation height of =2 m, by two to four observers,
along the shoreline at idle speed (2—3 knots).

Observer bias was relatively consistent because we collected the data on all
census days. We estimated group size, and recorded ventilation times and general
behavior of the cetaceans sighted. Results are given in averages + standard de-
viation (S.D.). Eleven species of odontocetes and two species of mysticetes were
observed.

34 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Table 1. Relative abundance of cetaceans of Isla de Guadalupe in 1991-1993, expressed as number
sighted per hour of effort (n = 101 observations).

Total number

Spring Summer Fall Winter (% of sightings)

Bottlenose dolphin 7 62 2, 2 T2286
Tursiops truncatus

Baird’s beaked whale l 4 2 l SZ.
Berardius bairdii

Unidentified Bottlenose whale _ 5 — — 4.95

Cuvier’s beaked whale 1 1 —_ a 1.98
Ziphius cavirostris

Unidentified beaked whale —- ] = — 0.99

Sperm whale — 2 — — L.9sS
Physeter catodon

Dwarf sperm whale —- ] — — 0.99
Kogia spp. ;

Common dolphin ] -- — l 1.98
Delphinus delphis

Risso’s dolphin = = — ] 0.99
Grampus griseus

Short-finned Pilot whale -= — 1 | 1.98
Globicephala macrorhynchus

Killer whales 1 | — —- 1.98
Orcinus orca

Blue whale = = a l 0.99
Balaenoptera musculus

Fin whale oe a a 1 0.99
Balaenoptera physalus

Total number of cetaceans 364 1241 84 76 1765

Hours of effort 180 840 240 160 1420

Number cetaceans/hour 2.02 |e) 0.4 0.5 1.24

Bottlenose dolphin, Tursiops truncatus

This was the most frequently observed cetacean year-round (Table 1). Group
sizes were recorded almost daily, averaging 19 + 12 individuals (range: 1—50
individuals, n = 73 schools). Bottlenose dolphins moved daily early in the morn-
ing (0600—0900 h), at a distance between 500 m and 3 km, parallel to the east
coast heading north and returned moving south inshore in the evening (from
1600—2000 h). It was common to observe a very spread formation of dolphins
moving slowly, apparently searching for prey. Upon finding a school of fish, aerial
displays started, which congregated the dispersed dolphins and started the herding
and encircling of fish schools. Immediately after this the dolphins chased the fish
into the shallows and started feeding on them. The same behavior has been re-
ported for T. truncatus from the Gulf of California (Gallo-Reynoso 1989). This
behavior was observed when they were feeding on skipjack tuna (Katsuwonus
pelamis) and yellowtail (Seriola lalandei). On other occasions, with the same
behavior, they fed on chub mackerel (Scomber japonicus), Pacific golden-eyed
tilefish (Caulolatilus affinis), red snapper (Lutjanus peru), and flying fish (Cyp-
selurus sp.). On 18 February 1991, at 11:30, while traveling along the east coast
of Isla de Guadalupe, we observed a group of.10 bottlenose dolphins that turned
toward us, crossed our bow, moving rapidly between the four foot waves. The

CETACEANS OF ISLA DE GUADALUPE 35

dolphins appeared to be fleeing from a 4.0—5.0 m great white shark (Carcharodon
carcharias) that was 30 m away and moving toward them. Interactions between
bottlenose dolphins and great whites have been reported by Connor and Heithaus
(1996). The dolphins escaped to the south moving fast and porposing out of the
water.

Baird’s beaked whale, Berardius bairdii

This was the second most observed odontocete in the study area. They were
observed year-round in groups averaging 4 + 0.9, individuals (range: 2-5, n =
8). These whales were identified by their size (9-13 m), their elongated, cylin-
drical beak and prominent melon. Calves (~5 m in length) were observed on
three occasions, two in June and july 1991 and one in November 1992. A juvenile
(~7 m in length) was observed in July 1991. These whales were on average
sighted 3.2 + 1.5 km offshore (range: 1—5.5 km). Dive times for these whales
averaged 26.5 + 8.5 min (range: 18-35, n = 8 dives). Twice on 8 July 1991,
when the whales sounded, yellowfin tuna (Thunnus albacares) started to jump
out of the water moving away from the whales.

Unidentified bottlenose whale

There were five observations of a large unidentified ziphid, similar to a bottle-
nose whale. They were observed only in the summers of 1992 and 1993. Gallo-
Reynoso and Figueroa-Carranza (1995) described them as Hyperoodon ampul-
latus, but there is no authenticated record of this species in the eastern Pacific.
In three occasions individuals of this species were breaching or partially breaching
which facilitated their identification, showing a whitish head, buff colored body,
squarish melon with short but well-defined beak, and falcate dorsal fin located
two-thirds of body length all characteristics of H. ampullatus (Leatherwood and
Reeves 1983). Size of breaching individuals was estimated at 7 m. Dive times
averaged 17.6 + 6.1 min (range: 10—25, n = 3 dives). These whales were diving
over waters 810 + 175 m (range: 600—1000, n = 5). During one observation, a
partially breaching whale was accompanied by a school of 25 bottlenose dolphins,
four of which were breaching with the whale for 10 min.

Cuvier’s beaked whale, Ziphius cavirostris

They were observed on two occasions. These whales were identified by their
brown coloration, white head with distinctive shape without a “‘beak’’, with many
white scar lines on the head and dorsum, and a triangular dorsal fin, situated far
in the back. A group of 7 individuals were observed in June 1991 at 300 m off
the coast. The largest individual was compared to the skiff (7 m) and estimated
to be 7.5 m. These whales were diving repeatedly in the same spot during four
hours of observation. Diving times averaged 21 + 10.2 min (range: 15-27, n =
16 divings). The group was accompanied by a school of 12 bottlenose dolphins
which were also diving. The second observation (July of 1991), consisted of 5
individuals, 2 km offshore, slowly moving to the north while diving. The areas
where these whales were diving averaged 565 + 49.5 m in depth (range: 535-—
600, n = 2).

36 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Unidentified beaked whale

Was observed in one occasion from a distance of 100 m. It had a non bulbous,
whitish head, with a distinctive beak (shorter than in young B. bairdii). The
dorsum was dark grayish-brown, with a few long white scars, and a broad falcate
dorsal fin situated far in the back (Leatherwood et al. 1988). The size of the
animal was about 5 m.

Sperm whale, Physeter catodon

Two observations on 28 July, 1993, 6.5 h apart (1233 and 1915 h) were possibly
the same individual. The sperm whale was at an average distance of 4.4 + 0.4
km (range: 4—4.8, n = 2), over waters more than 1000 m in depth. In the two
observations the whale was moving to the north.

Dwarf or Pygmy sperm whale, Kogia spp

A group of 12 individuals were observed from the camp in August 8, 1993 at
1816 h, at about 3 km offshore. They were recognized by its small size, the lack
of a conspicuous beak and their small but falcated dorsal fin found in the mid-
dorsum. Dive times averaged 40 + 15.7 min (range: 45—28, n = 4 divings). The
group was slowly moving north against the current.

Common dolphin, Delphinus delphis

This species was recognized by its small size, the presence of a short beak and
their characteristic clear coloration, compared to D. capensis. A large school of
about 250 individuals was observed in June 1983, moving fast to the south. A
second group, in February 1991, consisted of 15 individuals.

Risso’s dolphin, Grampus griseus

A group of 12 individuals (including two calves) were observed in 6 February,
1992 at 12 km northeast of the island. The group surfaced from the depth and
the younger individuals (judging by the size and darker coloration) rode the bow
wave of the ship for two minutes, then returned to the group. Water depth was
2980 m.

Short-finned pilot whale, Globicephala macrorhynchus

This species was observed on two occasions, a group of six whales in February
1991, and a group of eight in November 1992, heading south.

Killer whale, Orcinus orca

Fishermen reported 10 whales (including a calf) hunting elephant seals at Playa
Elefante (elephant seal beach) in June 1983. In August 1993, at 21:30 we regis-
tered the possible presence of this species as we heard from the camp at night
that the whales were slapping their flukes vigorously very close to shore, their
spouting was very strong. The fur seals were unusually silent, and a young ele-
phant seal, shaking violently was hauling out in rocks where they don’t normally
climb. The slapping continued for several minutes, coming from at least four
different locations. The slapping stopped when we searched with a light to identify
the animals. Apparently the whales left after this and we did not hear them again.
Although we never saw killer whales, the sound of their spouts and flukes slapping

CETACEANS OF ISLA DE GUADALUPE 37

in the surface and the behavior of the other marine mammals suggest their pres-
ence.

Blue whale, Balaenoptera musculus

We observed three individuals feeding close to Punta Sur (3 km), by doing
sideways movements with their mouths open. They were slowly moving to the
southwest at 1614 h on February 17, 1992.

Fin whale, Balaenoptera physalus

A large individual was observed 500 m offshore in February 1992. The whale
was lunge-feeding and moving to the south.

The cetacean fauna at Isla de Guadalupe is dominated by squid eaters (61.5%,
eight species): four species of beaked whales (Ziphiidae), two larger dolphins
(Delphinidae: Globicephalinae), the sperm whale (Physeteridae) and a species of
pygmy sperm whale (Kogiidae). There were also two fish and squid eating dol-
phins (Delphinidae) with 15.4%, and two zooplankton filtering whales (Balaen-
opteridae) with the 15.4%. One observed species has omnivorous habits (Del-
phinidae: Globicephalinae), with the 7.7%.

The composition of this cetacean fauna was somewhat different during the El
Nino event of 1992, with a higher sea temperature and sea level (Fahrbach et al.
1991). Sea surface temperatures we measured during summer was 5°C higher in
1992, and 3°C higher in 1993 than the mean of 20°C during 1991 (Gallo-Reynoso
1994). Probably the absence of Z. cavirostris and the presence of an unknown
bottlenosed beaked whale species, that was observed only in the summers of 1992
El Nino, and 1993 a post-E] Nino year were related to the shift of squid species
found during El Nino of 1992, in the diet of the Guadalupe fur seals. A greater
proportion of southern squid species was found in the scats of these fur seals than
in the previous year (Gallo-Reynoso 1994). é

The few observations of blue and fin whales and the absence of other species
of mysticetes may be related to the fact that the waters surrounding Isla de Gua-
dalupe have a moderate primary production of ~36—84 gC/m’yr according to
Koblents-Mishke and coworkers (in Berger 1989).

Acknowledgments

Direcci6n General de Intercambio Académico, Universidad Nacional Autonoma
de México (UNAM), The University of California Education Abroad Program,
and The National Geographic Society funded this research during 1991. The In-
stitute of Marine Sciences, University of California, Santa Cruz, funded during
part of 1992. UC-Mexus funded during fall 1992 and summer of 1993. The Di-
reccién General de Asuntos del Personal Académico, UNAM, funded in part from
1991-1993. We thank A. Delgado-Estrella, A. Sanchez and M. Peralta for their
help in the field. We thank Secretaria de Marina, and fishermen of ‘“Cooperativa
de langosteros y abuloneros de Ensenada” who provided transportation and lo-
gistic support. These observations were conducted under permits No. 0561 of
Secretaria de Pesca, and Nos. 2538, 4933 and 2025 of Secretaria de Desarrollo
Urbano y Ecologia (SEMARNAP), México. Finally we thank an anonymous re-
viewer that improved our work.

38 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Literature Cited

Berdegué, J. 1957. La Isla de Guadalupe, México. Contribucién al conocimiento de sus recursos
naturales renovables. Secretaria de Marina, Direcci6n General de Pesca e Industrias Conexas,
México. 67 pp.

Berger, W. H. 1989. Global maps of ocean productivity. Pages 429-455 in Productivity of the Ocean:
present and past. (W. H. Berger, V. S. Smetacek and G. Wefer, eds.). John Wiley and Sons
Limited.

Connor, R. C., and M. R. Heithaus. 1996. Approach by great white shark elicits flight response in
bottlenose dolphins. Marine Mammal Science., 12(4):602—60S.

Fahrbach, E., F Trillmich, and W. Arntz. 1991. The time sequence and magnitude of physical effects
of El Nifio in the Eastern Pacific. in Pinnipeds and El Nifio, responses to environmental stress
(F Trillmich and K. Ono, eds.). Springer-Verlag. pp. 8—21.

Fleischer, L. 1978. The distribution, abundance and population characteristics of the Guadalupe fur
seal, Arctocephalus townsendi (Merriam, 1897). Master in Science Thesis. University of Wash-
ington, Seattle. 93 pp.

Gallo-Reynoso, J. P. 1989. El bonito (Euthynnus lineatus) (Scombridae) como alimento para toninas
(Tursiops truncatus gillii) (Delphinidae) y por lobo marino (Zalophus californianus) (Otariidae).
Anales Instituto de Biologia. UNAM. Serie Zoologia., 60(1):125—127.

. 1994. Factors affecting the population status of Guadalupe fur seal, Arctocephalus townsendi

(Merriam, 1897), at Isla de Guadalupe, Baja California, México. Ph.D. dissert., University of

California, Santa Cruz. 199 p.

and A. L. Figueroa-Carranza. 1995. Occurrence of bottlenose whales in the waters of Isla
Guadalupe, Mexico. Marine Mammal Science., | 1(4):573—575.

Leatherwood, S., and R. R. Reeves. 1983. The Sierra Club handbook of whales and dolphins. Sierra
Club Books, San Francisco, California.

, R. R. Reeves, W. E Perrin, and W. E. Evans. 1988. Ballenas, delfines y marsopas del Pacifico
Nororiental y de las aguas articas adyacentes. Comision Interamericana del Atun Tropical. La
Jolla, California.

Lynn, R. J., and J. J. Simpson. 1987. The California Current system: the seasonal variability of its
physical characteristics. J. Geophys. Res., 92(c12):12,947—12,966.

Mangels, K. F, and T. Gerrodette. 1994. Report of cetacean sightings during a marine mammal survey
in the Eastern Pacific Ocean and the Gulf of California aboard the NOAA ships McArthur and
David Starr Jordan July 28—November 6, 1993. U.S. Dept. of Commerce. NOAA-TM-NMEFS-
SWFSC-211. 86 p.

Pierson, M. D. 1987. Breeding behavior of Guadalupe Fur Seal, Arctocephalus townsendi. in Status,
Biology, and Ecology of Fur Seals (J. P. Croxall and R. L. Gentry, eds.) NOAA TECN. Rep.
NMES. S1:83—94.

Accepted for publication 27 September 1997.

Bull. Southern California Acad. Sci.
97(1), 1998, pp. 39-48
© Southern California Academy of Sciences, 1998

A General Allometric Model for Blade Production in
Aostera marina L.

Elena Solana-Arellano, Dora J. Borbon-Gonzalez, and Hector Echavarria-Heras

Centro de Investigacion Cientifica Y Educaci6n Superior de Ensenada,
Baja California, México
Mail Address: P.O. Box 434844,
San Diego, California 92143-4844 U.S.A
email: hechavar@ CICESE.mx

Abstract.—We introduce a generalized allometric model to express leaf dry weight
in terms of leaf width and size in Zostera marina L. A formal justification of the
derived model is presented. For the statistical validation we used data collected
on two well defined strata over a period of one year. A comparison of the results
using an independent data set was also performed. Applications of the model to
estimate average leaf production are illustrated as well.

The seagrass ecosystem such as Thalassia testudinum Baks ex KOnig and Zos-
tera marina L. have an important role in shallow tropical and temperate waters.
These kinds of ecosystems are among the most productive marine systems. Con-
sequently many attempts to predict their response to changes in the environment
have been made. Most of the methods used to study marine phanerogams are
expensive, time consuming, and require destructive techniques such as leaf mark-
ing (Sand-Jensen 1975; Jacobs 1979). Moreover it has been shown that excessive
manipulation of raw material increases the error introduced in the data (Mandel
1964). Other techniques to measure seagrass production involve leaf cropping
(McRoy and McMillan 1977) but such methods influence leaf growth and phys-
iology (Hamburg and Homann 1986). In this paper we introduce a general allo-
metric model which simplifies the estimation of blade production for Zostera
marina. Our results could be applied to other marine phanerogams in a straight-
forward way.

The necessity to predict biomass and production for Zostera marina has stim-
ulated the development of allometric models in productivity estimations. Patriquin
(1973) used an allometric equation to predict leaf weight from leaf width for
Thalassia testudinum. Jacobs (1979) gives a relationship between shoot length
and density; McRoy (1970) relates leaf length and dry weight. Duarte (1991)
presents an allometric study for marine phanerogams which considers the rela-
tionship between the sizes of different parts of a plant. Nevertheless, he does not
include the variation of leaf dry weight in terms of length and width. Our allo-
metric model permits the reduction of the problem of blade production estimation
to the measuring of linear variates, particularly leaf length and width. For the
calibration of the model presented here we used data collected in two well-defined
strata over a period of one year. We obtained a remarkable consistency of the
model with the measurements. An alternate validation used independent data sets.

40 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

SAMPLE SITE
196m x 30m.

—-— TRANSVERSAL TRANSECT
—— COAST LINE APROXIMATION

[_] STRATUM I 2
02
STRATUM II f R, “zy
a ‘y
Z) G
UZ %Y
Ryu
%
Fig. 1. Location of the study site. Two strata were sampled, one at —0.8 to —0.2 below (MLLW)

(stratum I) and the other at —0.2 to O m below (MLLW) (stratum II).

(Solana et al. 1991). We also show the usefulness of the general allometric model
to estimate the time variation of average leaf dry weight. This is obtained in terms
of the allometric parameters and the leaf length and width averages. An example
of the referred estimation is illustrated. It uses the allometric parameters obtained
from our data and measurements of length and width obtained independently by
Ibarra-Obando (1992).

ALLOMETRIC MODEL FOR ZOSTERA BLADE PRODUCTION 4]

Field, Laboratory, and Statistical Methods

The study was carried out in an area located in San Quintin Bay, Mexico, a
coastal lagoon located in the Pacific Ocean waters of Baja California between
30°24’ and 30°30'N latitude and between 115°56’ and 116°01'W longitude. Ibarra-
Obando and Huerta-Tamayo (1987) give a complete description of San Quintin
Bay. The sampled site is a rectangular area 200 m by 30 m located in the arm of
the bay (see Fig. 1). Ibarra-Obando and Huerta-Tamayo (1987) showed that there
exist significant differences in the dynamics of Zostera marina L. between the
intertidal zone and the transition intertidal zone. Hence we used a topographical
study to determine two well-defined strata. Stratum I was from —0.2 m to —0.8 m
below Mean Lower Low Water (MLLW) and stratum II from 0 m to —0.2 m
below MLLW.

From November 1992 through November 1993 we sampled monthly eight
quadrants of 20 cm by 20 cm in each stratum following a stratified random
sampling (Wonnacott & Wonnacott 1984). We collected a total of 10,000 complete
leaves from stratum I and 9000 from stratum II. Each sample was placed in
individually labeled plastic bags and refrigerated until processed in the laboratory.
To produce our data each shoot was cleaned with distilled water. Measurements
of length and width were taken for each leaf, and then its dry weight was deter-
mined.

All the basic statistics and the fit of the model by means of non linear regression
was obtained using the STATISTICA package (STATISTICA 1993). Finally we
applied a goodness of fit test to corroborate that for both strata the regression
equation used was consistent with the data with a probability of 0.95.

Theoretical Methods

The model presented here generalizes the equation introduced by Hamburg and
Homann (1986). This relates leaf dry weight simultaneously with leaf size and
width. In their formulation these authors considered that leaf dry weight depended
linearly on leaf length and non linearly on width. Besides this restrictive assump-
tion they did not provide a formal justification to their model. Our theoretical
exploration shows that when length and width determine simultaneously the vari-
ation of leaf dry weight we must necessarily consider non linear dependencies in
both variables.

At time tf let w(x,t) (measured in mg) be the weight and /(x,f), h(x,t) (both
measured in mm) respectively the length and the width of a typical Zostera marina
L. leaf collected at a position x of the two dimensional sampling space. Consider
also that the measurement of the width is taken at the middle of the longitudinal
size of each leaf. According with Batschelet (1975) we have the allometric rela-
tionships:

L souer (ek el
5 9 SS SS gp = CD)
w or [ot
1 oh ko al
a @)
hor bot

Where k, and k, are positive constants.
The allometric laws (1) and (2) permit us to obtain the direct dependency of

42 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

dry weight with respect to leaf length or width. The simultaneous dependency on
both variables can be formally justified. To achieve this goal, we notice that
according to the chain rule (Fulks 1978) we have;

dw OW ol ow oh

amma! ay an are @)
Combining equations (1), (2) and (3) we obtain,
k\w ol _ ow ohh Sly tel al ky
“tat al ot oh ar
Simplifying we can establish the partial differential equation;
> te lah = kw. (4)

In the appendix we have shown that a solution to equation (4) which satisfies
the allometric relations (1) and (2) becomes,

w(x,t) = Kh(x,t)*1(x,t)® (5)

where k, a and B are constants that can be obtained from the data.

The allometric model given by equation (5) can be used to estimate the dy-
namics for average leaf production using measurements of leaf size and width.
Let us consider a set of leave samples. Suppose that the mth sample contains N,,,
complete leaves collected at a time ¢. Then for the ith leaf in that sample equation
(5) gives

W seas t) a KIM OG) Up Xyisk)” (6)

where W,,(Xnist)s Am(Xmist), and L,,(x,,;¢) are respectively the dry weight, the width
and length of the considered leaf. In our notation, the sub-index mi identifies a
leaf collected at a position x,,,; and belonging to the mth sample for 1 = 7 S N,,,.

Taking logarithms in (6) and averaging we have

mi?

1 Nin OL Nin B Nin
N. > (in Wmi(Xmis t)) = In K aE Na > In Has Mie t) air N,. > In L ni(Xmis t) (7)

m t=) m t=

The left hand side of equation (7) gives the natural logarithm of the geometric
mean of the set of N,, dry weight values in the sample. This equation also permits
the exploration of the validity of equation (5) for different data sets. It is worth
to point out that the variability observed in the measurements makes the geometric
mean of dry weight a better estimator of central tendency for leaf dry weight. On
the other hand the use of logarithms in equation (7) will avoid the vanishing
effect associated to the large product of small numbers required to obtain the

referred mean.

Results

Using the collected data, we tested the model given by equation (5). We ob-
tained very similar results for both strata (see Table 1). No spatial dependencies
for the allometric parameters x, a and B along the strata where detected. For
stratum I and stratum II the coefficients of determination were 0.91 and 0.87

ALLOMETRIC MODEL FOR ZOSTERA BLADE PRODUCTION 43

Table 1. Estimations for both strata of the fitted parameters and their respective standard errors.
Stratum I Stratum II Std. error Stratum I Std. error Stratum II
K 0.000005 0.000015 0.04(p < 0) 0.03 (p < 0.0)
a 1.09 3 0.01 (p < 0.05) 0.01 (p < 0.0)
B 0.469 0.45 0.04 (p < 0.05) 0.03 (p < 0.0)

respectively. The standard error for the estimate was 0.43 for stratum I and 0.55
for stratum II. For both cases the parameters found in the regression have very
small standard errors and very significant p-values (see Table 1). The residual
analysis for both strata gave no indication of lack of fit of the model.

Plots of the predicted and observed values of leaf dry weight are presented for
each stratum to provide a visual interpretation of the adequacy of the fit (see Fig.
2). Finally a lack of fit F-test was applied to data in both strata. We obtained
significant evidence that the expected value of the dependent variable w is indeed
represented by means of the allometric equation (5) with a probability of 0.95.

Using data collected on a preliminary sampling, Solana et al. (1991) found
similar values for the parameters xk, a and B. This was corroborated using a
Student-t test at a 95% confidence level. As a conclusion equation (5) gives the
correct allometric relationship for the involved variables in our study site.

An application of the present model was performed. Using the values of the
parameters x, a and 6 corresponding to our data, we simulated the behavior of
the average mean dry weight as given by equation (7). For that purpose we used
an independent data set for leaf length and width collected by Ibarra-Obando
(1992) in the same MLLW level of stratum I. Fig. (3) shows the temporal variation
of the average dry weight obtained directly from our data and the predicted by
quation (7) for the Ibarra-Obando (op. cit.) data set. Using analysis of variance
and a LSD (Least significant difference) test, we found no significant differences
between both means. This shows that the sample paths shown in Fig. (3) are both
generated by the same stochastic process. This also implies the consistency of the
considered allometric relationship.

Discussion

The characterization of productivity for the eelgrass Zostera marina both under
laboratory and in situ conditions has been relevant in the study of the ecology of
the seagrass ecosystem. The advantages of allometric relationships in these studies
are pointed out by several authors e.g., (Jacobs 1979, McRoy 1970, Duarte 1991,
Patriquin 1973, Hamburg and Homann 1986). An allometric description of dry
weight in terms of direct in situ measurements could avoid tedious laboratory
processing and destructive sampling. The model we tested here permits the ex-
pression of leaf dry weight in terms of leaf length and width through a simple
equation whose parameters are easily obtained using available nonlinear regres-
sion methods. Although a form close to the proposed model was introduced by
Hamburg and Homann (1986) no formal justification was provided. Furthermore
the model proposed by these authors considers linear dependence of dry weight
with respect to leaf length. That model fails to provide the generality of the
allometric equations (1) and (2). On the other hand, as it is shown in the appendix,

44 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

stratum |
0.16
0.14
0.12
o = Ad
=
BS 2 0.08
>sG
o>
Hn &
8&5 0.06

0.04
0.02
0 ~s. Regression
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 95% confid.
Predicted Values
(Leaf dry weight)
stratum II

Observed Values
(Leaf dry weight)

“ea. Regression
0.14 95% confid.

0 0.02 0.04 0.06 0.08 0.1 OraZ

Predicted Values
(Leaf dry weight)

Fig. 2. Predicted vs. observed values of leaf dry weight predicted by equation (5) in terms of leaf
length and width. a) Stratum I. b) Stratum II. To produce these plots we selected a random sample of
1000 leaves.

the model given by equation (5) can be justified using the results in the theory
of first order partial differential equations. We conclude that an allometric relation
in the form proposed here must necessarily be considered in order to express leaf
dry weight in terms of length and width measurements.

The model that we present here provides a simple procedure to identify the

ALLOMETRIC MODEL FOR ZOSTERA BLADE PRODUCTION 45

0.014

0.012

0.01

0.008

0.006

0.004

natural logarithm of the geometric mean
of leaf dry weight

0.002

TIME (months)

Fig. 3. Variation over time natural logarithm of the geometric mean of leaf dry weights. The
continuous line corresponds to our data. The dashed line represents the simulation of the mean leaf
dry weight predicted by equation (7) using data on leaf length and width obtained by Ibarra-Obando
(1992) and the allometric scaling parameters k, a and B found in the present study.

allometric scaling factors for the considered variables. The high determination
coefficient obtained for the data sets analyzed in this study corroborate the claim
that our model is consistent with these observations. Our model was also tested
against independent data sets. In a preliminary application of our model using
only 21 shoots in a single sample, Solana et al. (1991) found similar values for
the allometric parameters. A Student-t test gave no indication of statistical dif-
ferences. Hence we can expect that the values obtained for the allometric param-
eters k, a and B will not depend on the particular data set considered. As a
conclusion the model given by equation (5) identifies unambiguously the allo-
metric linkage which relates the variation of the leaf dry weight as a function of
leaf length and width for Zostera marina L. in our study site. When we used the
values of parameters xk, a and £6 found with our data to obtain by means of
equation (7) the dry weight corresponding to data on length and width (Ibarra-
Obando 1992) we observed some deviations with respect to the corresponding
values measured in our study. As we have pointed out, these characterizations of
the temporal variation for the leaf mean dry weight portrayed in Fig. (3) corre-
spond to sample paths of the underlying stochastic process. Nevertheless these
deviations could be explained by the occurrence of a strong “El Nino Southern
Oscillation’? (ENSO) event which took place from June 1986 to January 1988;
that is just before and during the year where the data were taken (Climate Di-
agnostic Bulletin 1996). Solana et al. (1996) found that temperature is the most
significant variable in the determination of leaf size dynamics in our study site.
In the same study, dissolved nutrients were also found to be a determinant. The
ENSO event was reported to induce an increase of water temperature and a re-

46 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

duction of dissolved nutrients in San Quintin Bay (Silva-Cota and Alvarez-Bor-
rego 1988). By virtue of the tolerance law, the rise in water temperature could
have produced sub-optimal leaf growth rates. High temperature stress has been
claimed to induce a deleterious effect for Zostera marina (Rasmusen 1977). It
has also been reported that a sizeable increment in temperature reduced shoot
abundance and a change in the seasonal pattern of abundance of Z. marina in
Chesapeake Bay (Penhale 1977; Wetzel and Penhale 1983; Evans et al. 1986). In
our study site the reduction of nutrients could have also contributed to the pre-
dicted reduction of average leaf dry weight. The conjunction of high temperature-
stress and a reduction in dissolved nutrient availability could have created a de-
layed response characterized by a smaller leaf production which was observable
in summer of 1987.

Given the values of the allometric parameters equation (7) becomes an adequate
tool to estimate leaf production in Zostera marina L. (see Fig. 3). We claim that
our model is a general tool which could be straightforwardly applied in other
studies. This will simplify biomass estimations, eliminating tedious laboratory
processing while avoiding destructive sampling.

Acknowledgments

We thank Fernando Escoto and Hector Atilano-Silva for their fine laboratory
work. This paper is part of the research on eelgrass production partially funded
by CONACYYT, by grant 0263-N9107. Roberto Iglesias-Prieto provided valuable
suggestions and references. His orientation is greatly appreciated.

Literature Cited

Batschelet, E. 1975. Pp. 362—364. in Introduction to mathematics for life scientist. Springer Verlag.

Duarte, C. M. 1991. Allometric scaling of seagrass form and productivity. Mar. Ecol. Prog. Ser., 77:
289-300.

Evans, A. S., K. L. Webb, and P. A. Penhale. 1886. Photosynthetic temperature acclimation in two
coexisting seagrasses, Zostera marina L. and Ruppia maritima. L. Aquat. Bot., 24:185—197.

Fulks, W. 1978. Advanced Calculus. John Wiley and Sons Inc. New York. 500 pp.

Hamburg, S. P., and P. S. Homann. 1986. Utilization of growth parameters of eelgrass, Zostera marina,
for productivity estimation under laboratory and in situ conditions. Mar. Biol., 93:299-—303.

Ibarra-Obando, S. E., and R. Huerta-Tamayo. 1987. Blade production of Zostera marina L. During
the Summer-Autumn on the Pacific coast of Mexico. Aquat. Bot., 28:301-—315.

1992. Contribution a la connaissance de lherbier a Zostera marina en Bajja California
(Mexique): Biologie et Production Primaire. Thése de Doctorat, Université d’ Axi-Marseille I,
France, 286 pp.

Jacobs, R. P. W. M. 1979. Distribution and aspects of the production and biomass of eelgrass, Zostera
marina L., at Roscoff, France. Aquat. Bot., 7:151—172.

Mandel J. 1964. The Statistical Analysis of Experimental Data. Dover Publications, Inc. New York.
410 pp.

McRoy, C. P. 1970. Standing stock and other features of eelgrass (Zostera marina) populations on
the coast of Alaska. J. Fish., 27:1811—1812.

, and C. McMillan. 1977. Production, ecology and physiology of seagrasses. pp. 53-87 in
Seagrass ecosystems as scientific perspective. (C. P. McRoy and C. Helfferich, eds.), Marcel
Dekker New York.

Patriquin, D. G. 1973. Estimation of growth rate, production and age of the marine angiosperm,
Thalassia testudinum. Koenig Carib. J. Sci., 13:111—123.

Penhale, P. A. 1977. Macrophyte-epiphyte biomass and productivity in an eelgrass (Zostera marina
L.) community. J. Exp. Mar. Biol. Ecol., Vol. 26, pp. 211-224.

Rasmussen, E. 1977. The wasting disease of eelgrass (Zostera marina) and its effects on environ-

ALLOMETRIC MODEL FOR ZOSTERA BLADE PRODUCTION 47

mental factors and fauna. pp. 1-51 in Seagrass ecosystems, a scientific perspective, (C. P.
McRoy & C. Helffrich, eds.), Marcel Dekker, New York.

Sand-Jensen, K. 1975. Biomass net production and growth dynamics in an eelgrass (Zostera marina)
population in Vellerupo Vig. Denmark. Ophelia, 14:185—201.

Silva-Cota S., and S. Alvarez-Borrego. 1988. The ‘‘El nino” effect on the phytoplankton of a North-
western Baja California coastal lagoon. Estuarine, Coastal and Shelf Science, 27:109—115.

Solana-Arellano, M. E., S. E. Ibarra-Obando, and H. Echavarria-Heras. 1991. Calibraci6n de un
modelo alométrico para evaluar produccion foliar de Zostera marina L. Hidrobioldégica, 1(2):
41-11.

, H. Echavarria-Heras H., and S. E. Ibarra-Obando. 1996. Leaf size dynamics for Zostera
marina L. In San Quintin Bay, Mexico: A theoretical study. Estuarine, Coastal and Shelf Sci-
ence. (in press)

Wetzel, R. L., and P. A. Penhale. 1983. Production ecology of an eelgrass community in the lower
Chesapeake Bay. Mar. Tech. Soc., 17:22-31.

Zachmanoglou, E., and D. W. Thoe. 1976. Introduction to Partial Differential Equations with Appli-
cations. Williams and Wilkins Company, pp. 60-62.

Wonnacott T., and R. Wonnacott. 1984. Introductory Statistics for Business and Economics. John
Willey and Sons Inc. New York, pp 614-627.

Appendix

According to theorem 2.1 in Zachmanoglou and Thoe (1976) (pages 60-61), the solution w = f(h,/)
of equation (5) is given implicitly by the relation:

F(u,(h,Lw),u(h,lw) ) = 0 (Al)

Where F is a function of class C! and u,, u, are two functionally independent solutions of the
auxiliary system:

dl_— dh dw
—= = — (A2)
l k,h kw
From the system (A2) we can obtain by direct integration
l ly
a (A3)
he he
Ue ie
ope (A4)
W Wo

Where wo, /) and hy are respectively the dry weight, the length and width of a leaf at the
beginning of the growing process and a and 6 are constants defined in terms of the allometric
scaling factors k, and k, (see equation (1) and (2)) trough the relationships

= (— AS
" a

o=k, (A6)
From equations (A3) and (A4) we see that the functions u, and uw, defined according to

u,(h, L w) = a (A7)
he
u,(h, l, w) = a (A8)

satisfy
grad(u,) X grad(u,) ~ O

in the region / > O, h > O and w > O. Then in general u, (h, 1, w) = c, and wu, (h, 1, w) = c,
where c, and c, are constants, define two functionally independent solutions of the auxiliary

48 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

system (A2). Hence for u, and u, as given by equations (A7) and (A8) the implicit relation
(Al) gives the general integral to p.d.e. (4).
From equations (A7) and (A8) it is easily seen that

io = Ls voles (A9)
he wiih,

hence for u, and u, as defined above we have
u, — cu, = O (A10)

Where c is a constant that can be identified using equation (A9). Consequently equations (A1),
(A10), the choosing

E(u, Us) = Uy — Cl
and the implicit relation (Al) permit to conclude that the function
w = Khel®

Where B = 6 — | is a solution to equation (4) which also satisfies the allometric equations (1)
and (2).

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CONTENTS

Temporal Changes in Diet.and Foraging Habitat of California Killifish (Fun-
dulus parvipinnis) in Marina del Rey, California. By Kristine Beh-
rents Hartney and Lusine Tumyan

Polychaete Fauna from San Quintin Bay, Baja California, Mexico. By V.
Diaz-Castaneda and V. Rodriguez- Villanueva

Cetaceans of Isla De Guadalupe, Baja California, Mexico. By Juan-Pablo
Gallo-Reynoso and Ana-Luisa Figueroa-Carranza

A~ General Allometric. Model for Blade Production in Zostera marina
L. By Elena Solana-Arellano, Dora J. Borbon-Gonzales, and Hector
Echavarria-Heras

COVER: Common Dolphin (Delphinus delphis) near Isla de Guadalupe. Photo by
Juan-Pablo Gallo-Reynoso.

7. te

Pee neERN. -CALIFORNIA ACADEMY OF: SCIENCES

BULLETIN

Volume 97 Number 2

BCAS-A97(2) 49-88 (1998) AUGUST 1998

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Date of this issue 3 August:.1998

CALIFORNIA
ACADEMY OF SCIENCES

AUG 1 9 4998

LIBRARY

Bull. Southern California Acad. Sct.
97(2), 1998, pp. 49-75
© Southern California Academy of Sciences, 1998

Range Extensions of Ten Species of Bats in California

Denny G. Constantine

1899 Olmo Way, Walnut Creek, California 94598

Abstract.—Ten rare or uncommon species were among some 22,000 bats identi-
fied after being tested for rabies in California: Macrotus californicus, Choeron-
ycteris mexicana, Leptonycteris curasoae, Myotis velifer, Lasionycteris noctiva-
gans, Lasiurus blossevillii, Lasiurus xanthinus, Nyctinomops femorosaccus, Nyc-
tinomops macrotis, and Eumops perotis. Numerous geographic range extensions
were among 194 new localities reported. Perceived range extensions of southerly
species may be due to either increased sampling, global warming or other factors.
Identification by professional taxonomists of host animals tested for pathogens is
encouraged to save valuable data and as prerequisite to disease problem compre-
hension and resolution.

New geographic range records and associated data have resulted from the iden-
tification of more than 22,000 bats tested for rabies in California. Distributional
highlights of 425 bats of ten generally rare or uncommon species, nearly all
supported by preserved specimens, are presented here, whereas additional distri-
butional, population, ecological, and rabies epidemiological studies of these and
common species are in progress.

Methods

The author periodically identified bats tested for rabies in California subsequent
to his first bat rabies survey in the state in 1954 (Enright et al. 1955), but it was
not until 1977 that he did so regularly, if on a voluntary basis. Counties that could
cooperate shipped the carcasses of bats they had tested to the author, who was
employed at the California Department of Health Services in Berkeley.

Other workers participated in identifications in early years. Keith EK Murray
made several determinations cited in Constantine et al. (1979). Beginning in 1973
and ending in 1981, former Los Angeles Department of Health Services biologist
Loran M. Whitelock, who earlier had worked on bats with the author, performed
bat identifications for that county. Personnel took relevant health precautions
(Johnson 1979: Constantine 1988), including preexposure rabies immunizations.

Nearly all carcasses were damaged and decomposed when received, and the
cranium had been opened to remove the brain, destroying key characters needed
to differentiate some species. Most rare or uncommon bats were salvaged as
skeletons or in fluid preservatives, and a few were prepared by the author as study
skins, despite some hair slippage.

Measurements are presented to support certain critical identifications. Different
measurement methods were sometimes used for different species in order to match
techniques used by authors of relevant published studies and thus facilitate com-
parisons by the reader. Most external measurements were made with a rule. Fore-
arm, wing digit, and cranial measurements were made with dial calipers.

50 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Most new locality records are merely listed, in accordance with the limited
purpose of this report, relevant details being reserved for other reports, but the
more unexpected records are given in detail. Plant communities, cited in reference
to especially unusual locality records to reflect ecological parameters, are from
Kuchler (1977).

Maps bear a single symbol for each new (closed circle) or previously published
(open circle) locality. Symbols do not reflect the numbers of reports or specimens.
Museum catalog numbers and other details are generally given only for specimens
that represent peripheral range extensions, although a few of these bats have not
yet been cataloged. Recipient museums are the Museum of Vertebrate Zoology,
University of California, Berkeley (MVZ) and the Natural History Museum of
Los Angeles County (LACM).

Results

California leaf-nosed bat
Macrotus californicus Baird 1858

This insectivorous species has been reported from northern Sinaloa and south-
western Chihuahua, Mexico northward through Sonora and Baja California to
southern California, extreme southern Nevada, and southern Arizona; an appar-
ently disjunct population has been reported in Tamaulipas, Mexico (Koopman,
1993). The species is included herein primarily to report recent observations at
reported and unreported westernmost stations of known occurrence.

Howell (1920b), referring to this species in a cave (see photograph in Howell’s
paper), said to be 2 mi N of Owensmouth, Los Angeles Co., reported six of the
bats present on 6 April, none on 4 June, and about thirty on 14 December (years
not given). Owensmouth has been renamed Canoga Park. The cave, about 24 m
deep and 9 m high in calcareous conglomerate, was called Vanowen Bat Cave
by Halliday (1962) after the author took him there. It was found to be in the first
canyon south of Bell Canyon, about 6.6 km W of Canoga Park and just inside
Ventura Co. some 0.97 km W of the present end of Vanowen Street at Sunset
Ridge Court. On 30 January 1949, I observed three Macrotus on the cave ceiling.
Identified by their large ears, nose leaves, and “‘twirling’’ when hanging by one
foot to watch the observer, they were not disturbed further. No bats were seen in
the cave on subsequent visits made February 1953, 4 July 1989, and 27 April
1990:

A second cave, this one in Los Angeles Co. about 10.31 km NNE of the first
cave and about 3.32 km NNW of Chatsworth, was found by Thomas Cade and
Gary Casey to contain a small group of these bats on 8 May 1947, when six were
collected, prepared as skins, and given to the LACM. I joined them on a visit to
the cave later that month, when several Macrotus skeletons were found on the
cave floor. Mark Ryan collected a bat at this cave 15 June 1950 (MVZ 113637).
The cave was a dugout under several large adjacent boulders on an extensive
boulder-strewn property known as the Iverson Ranch. The area has since been
bisected by a freeway and subdivided for housing, with much ground surface
distortion. A search for the cave by the author and Kenneth E. Stager in April
1990 was unsuccessful.

Only four Macrotus are known to have been submitted for rabies testing in

RANGE EXTENSIONS OF BATS IN CALIFORNIA 51

Choeronycteris
mexicana

Oo published
@® new

100 mi.
Ee a |
100 km.

Fig. 1. Known distribution of the Mexican long-tongued bat, Choeronycteris mexicana, in Cali-
fornia.

California, as expected for a species that prefers living far from human habitat.
They were from within the known range in Imperial, San Bernardino, and San
Diego counties.

Mexican long-tongued bat
Choeronycteris mexicana Tschudi 1844

This nectar, pollen, and fruit-eating bat has been reported from El Salvador and
Honduras (Arroyo-Cabrales et al. 1987) northward through Mexico, including
Baja California, to San Diego, California (Olson 1947), southern Nevada (Con-
stantine 1987), southern Arizona (Hoffmeister 1986), southwestern New Mexico
(Findley et al. 1975), and extreme southern Texas (LaVal and Shifflett 1971).

The first observations of this species in California were made September to
December 1946, during an “‘invasion’”’ by the species, in San Diego, San Diego
Co. Fifty of the bats were collected, usually as individuals found hanging in dimly
lit sites about buildings, but as many as 40 to 50 were seen at one place and
time, with probably 75 total bats being detected (Olson 1947; Huey 1954b). Bond
(1977) mentioned that subsequent San Diego specimens were obtained in October
of 1947 and 1963 and in December 1947. Banks and Parrish (1965) reported
another specimen taken 15 October 1963 from Lemon Grove, at the eastern edge
of San Diego.

I have received 15 additional bats of this species: 10 from five localities in San
Diego Co., three from at least two localities in Orange Co., one from Los Angeles
Co., and one from Ventura Co. Unfortunately, labels came off individual con-
tainers within two frozen shipments, so data on two of these bats (one each from
Los Angeles and Orange counties) were lost (Fig. 1, Appendix).

The San Diego Co. bats do not represent remarkable range extensions. The first
Orange Co. bat, a female (MVZ 181846), was taken at an unknown place and
date between 1976 and 1978. The second, a male (MVZ 186389), was taken at
San Clemente 28 September 1993. The third, a male (LACM 94031), was found
at Tustin on 24 November 1995. The Los Angeles Co. bat, a female (MVZ

32 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

181845), was taken at an unknown locality and date between July and December
1988. The Ventura Co. bat, a male (LACM 94032), was found 15 November 1994
at Ventura, 260 km NW of San Diego.

This species, one of three leaf-nosed bats now known in California, is readily
differentiated from the other two. Macrotus has huge ears compared to the rela-
tively short ears of Choeronycteris and Leptonycteris. The latter lacks an evident
tail, whereas the short and exsert tail of Choeronycteris arises from the dorsal
surface of the interfemoral membrane near its base.

Southern long-nosed bat
Leptonycteris curasoae yerbabuenae
Martinez and Villa-R. 1940

These nectar and pollen eating bats are reported to appear in southern Arizona
in spring, produce offspring in colonies within caves and mine tunnels, and dis-
appear in fall, evidently returning south into Mexico (Hayward and Cockrum
1971; Hoffmeister 1986). Arita and Humphrey (1988) considered L. curasoae to
be divisable into two subspecies: (1) L. c. verbabuenae, distributed from southern
Arizona, New Mexico, and Tamaulipas, Mexico southward to Guatemala and El
Salvador, and (2) L. c. curasoae, thus far known as a disjunct population in
northern Colombia and Venezuela and nearby Caribbean islands. The species is
reported herein for the first time from California, where two bats were found,
each in a different county in the southern part of the state.

The first bat was found in suburban Yucaipa, 799 m elev., San Bernardino Co.,
formerly characterized by coastal sagebrush, adjacent to chapparal-covered hills.
At about 1100 h PDT, 3 October 1993, a male bat (MVZ 186390) was inadver-
tently flushed from a shaded site behind a meter-high bush growing next to the
outer side of a residence chimney, which was flush against the south side of a
one-story house. The bat flew about 4.6 m through the back door and into the
shade of a screened carport-patio, where it was captured. After brain removal, the
carcass was frozen and sent to the author four months later, when it was made
into a study skin with skeleton, and other tissues were saved. Dehydration pre-
cluded getting reliable ear and weight measurements.

The second bat, a male (LACM 94033), was found in urban Oceanside, 14 m
elev., San Diego Co., an area of former coastal sagebrush adjacent to chapparal
and southern oak forest. The bat was observed at 900 h PDT 18 October 1996
hanging outside under a canopy over the front door of a business concern. The
frozen carcass was received by the author four months later, when it was prepared
as a study skin and skeleton. The bat had considerable deposits of subcutaneous
fat throughout but especially in the neck, interscapular, and leg base areas.

The bats were identified as L. curasoae and not Leptonycteris nivalis by com-
paring them with skins and literature. Measurements were made using methods
described by Arita and Humphrey (1988), except bilateral measurements were
taken, where applicable, and averaged. The hair coat was typically short and
dense, and the hair fringe on the border of the uropatagium was inconspicuous.
The presphenoid ridge was prominent and rounded. Recoverable measurements
(Table 1) were consistent with those published for samples of bats designated L.
c. verbabuanae from Morelos and Colima, Mexico by Arita and Humphrey
(1988), from Baja California Sur, Mexico (as L. sanborni) by Woloszyn and Wo-

Nn
OW

RANGE EXTENSIONS OF BATS IN CALIFORNIA

Table 1. Leptonycteris Curasoae: measurements (mm) and weight (g).*
Yucaipa, San Oceanside
Bernardino Co San Diego Co
Measurement 3-X-1993 18-X-1996
Total length 70 81
Length of foot 14.4 14.0
Length of ear from notch 7/0)
Length of folded forearm 53.70 52295
Length of 3rd digit 99.45 oe )al 3)
Length of 3rd metacarpal 49.05 49.65
Length of Ist phalanx of 3rd digit 14.58 13.75
Length of 2nd phalanx of 3rd digit 23.47 2375
Length of 3rd phalanx and cartilage of 3rd digit 35 12.00
Condylobasal length Pasytes0) 26s lg)
Greatest cranial length excluding incisors 2ORS5
Zygomatic width 10.30 10.78
Least interorbitai width 4.35 4.40
Greatest width of braincase 10.09 9.98
Greatest width at mastoids 10.80 10.64
Width of rostrum at last maxillary molars 6.60 6.40
Length of palate excluding spine 14.14 14.18
Length of maxillary tooth row excluding incisors 9.00 8:95
Length of mandible 17.98 18.10
Length of mandibular tooth row excluding incisors 9.48 AE |
Weight (less brain) DOD

* Methods are from Arita and Humphrey, 1988.

loszyn (1982), and from Arizona (as L. nivalis sanborni and later as L. sanborni)
by Hoffmeister (1957, 1986).

The present known distribution of L. c. verbabuenae in the United States and
northwestern Mexico is indicated in Fig. 2.

Yucaipa, the new northernmost locality where the species is known, is 463 km
west and slightly north of the previous northernmost locality at Glendale, Mari-
copa Co., Arizona (Constantine 1966), 420 km NNW of the previous westernmost
locality in the United States at Agua Dulce Mountains, Pima Co., Arizona (Cock-
rum and Petryszyn 1991), and 823 km NNW of the northernmost Baja California
Sur, Mexico, locality at Santa Rosalia (Arita and Humphrey 1988). Oceanside is
98 km SSW of Yucaipa.

Cave myotis
Myotis velifer velifer (J. A. Allen 1890)

This insectivorous species is known to occur from the southeastern California
and Nevada borders at the Colorado River to Kansas and southward through
mainland Mexico and Guatemala to El Salvador and Honduras (Hayward 1970;
Helebuyck et al. 1985). The subspecies M. v. velifer reportedly occupies the west-
ern and southern parts of the range. Hayward (1970) concluded that the smaller
bat of the southern end of Baja California Sur, Mexico, classified as M. v. pen-
insularis by Miller and Allen (1928), is a separate sibling species, M. peninsularis,
as originally determined by Miller (1898).

Found during warm months in California only near the Colorado River, aggre-

54 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Leptonycteris
curasoae

Fig. 2. Known distribution of the southern long-nosed bat, Leptonycteris curasoae yerbabuenae,
in the southwestern United States and northwestern Mexico. From Arita and Humphrey (1988), Cock-
rum and Petryszyn (1991), Hoffmeister (1986), and the present study.

gations of this presumably migratory subspecies previously were common in
abandoned mine tunnels, where its numbers have been drastically reduced. Three
bats of this species are reported herein from Los Angeles Co., a surprising distance
westward from the former westernmost known boundary of the species.

The first bat, a female (MVZ 186397), was captured after it flew through a
door into a house during daytime 28 September 1992 at Florence, 49 m elev., an
urban area originally of coastal sagebrush. The scalped carcass was received by
the author the next month when it was salvaged as a skin and skeleton, although
it was decomposed with extensive hair slippage.

The second bat, a male (MVZ 186398), was found alive during daylight the
morning of 28 November 1994 clinging to an overhang above a door at Valencia,
303 m elev., in a parklike suburban setting with adjacent chapparal and riparian
vegetation. The scalped, decomposed and somewhat dessicated carcass was sent
to the author some six months later when it was salvaged as a skin, legs and tail
vertebrae contorted within the shriveled uropatagium, and skeleton with skull
fragments.

The third bat, a male (LACM 94035), whose canines were shortened by wear,
was captured about 1900 h PST 27 March 1997 while hanging in a covered
entryway outside the front door of a residence at Lancaster, 718 m elev. Areas
representing three plant communities meet in the vicinity: Joshua tree scrub, Mo-
jave creosote bush, and desert saltbush. I received the partially decomposed car-
cass the following month and salvaged it as a skin and skeleton.

Some external and recoverable cranial measurements of the three bats are pre-

RANGE EXTENSIONS OF BATS IN CALIFORNIA =)5)

Table 2. Myotis velifer from Los Angeles Co: measurements (mm) and weight (g).*

Florence Valencia Lancaster
Measurement 23-IX- 1992 28-XI-1994 3-XII- 1996

Total length 95 98 o5
Length of tail 4] 43 42
Length of foot a0 7 10.0
Length of ear from notch 1325 14.5
Length of forearm 42.75 44.05 42.40
Occipitonasal length 15:70 15.86
Condyle-premaxillae length (C) 15.05 14.94
Cranium breadth TD 8.10 7.78
Mastoid breadth 7.85 8.08
Rostrum breadth (H) 4.53 4.21 4.60
Least interorbital breadth 3.D> 4.05 3165
Braincase depth (H) 5502 (SHA
Maxillary tooth row length 6:33 6.18 632
Length of mandible (C) PEAT 11.99 12.29
Mandibular tooth row length (C) 6.71 6.66 6.67
Weight (less brain) 6.9

* Methods are from Hayward, 1970, who cited Cockrum, 1955 (C), from Hoffmeister, 1986 (H), or
from both where identical methods were used.

sented in Table 2, and localities of collection are indicated in Fig. 3 and the
appendix.

The measurements of the three bats are consistent with those given by Grinnell
(1918), Miller and Allen (1928), Stager (1939), Vaughan (1954), Hayward (1970),
and Hoffmeister (1986), although there are some differences between these au-
thors possibly referable to methods or specimen sexes and ages.

The long forearms of these three bats separate them from all other members

ORS SSS SSS CS SRS SSCS SSO e ay

Myotis
velifer

ate ee rE A Soo tte eT a PCat a

100 mi.

200 km.

Fig. 3. Known distribution of the cave myotis, Myotis velifer velifer, in California and adjacent
border areas.

56 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

of the genus known from the United States except M. volans, M. thysanodes, and
the southeastern M. grisescens. However, like velifer they lack the rounded ears,
furred basal wing membranes, and keeled calcar of volans, the fringed uropata-
gium and larger ears of thysanodes, and the unicolored dorsal hairs and tarsal
wing attachment of grisescens.

Valencia, Los Angeles Co., is now the westernmost known locality for this
species and is 377 to 482 km W of the previously reported westernmost localities
at or near the Colorado River as follows:

Jackass Flats, Clark Co., Nevada (Cockrum and Musgrove 1964)

Needles, San Bernardino Co., California (Grinnell 1918)

Parker, La Paz Co., Arizona (Hoffmeister 1986)

Riverside Mountains, Riverside Co., California (Stager 1939)

Blythe, Riverside Co., California (LACM 13626)

Picacho, Yuma Co., Arizona (Hoffmeister 1986)

Valencia is distant from the other two Los Angeles Co. localities as follows:
52 km WSW of Lancaster, and 62 km NNW of Florence.

The three cave bats from Los Angeles Co. are the only bats of that species
known to have been tested for rabies in California.

Silver-haired bat
Lasionycteris noctivagans (Le Conte 1831)

This insectivorous and presumed migrant has been reported from forested areas
throughout North America from southeastern Alaska across the southern half of
Canada and southward to or near the southern border of the United States ex-
cluding Florida, southwestern Arizona, and southern California (Hall 1981; Kunz
1982). Thus far, only one bat has been reported from Mexico, in Tamaulipas,
south of Texas (Yates et al. 1976). The species is also known to occur during
spring and fall in Bermuda, evidently as wind-blown migrants from the east coast
of North America (Van Gelder and Wingate 1961).

The distribution of this species in California is generally depicted on maps to
include and extend from the northern third of the state southward along coastal
mountains to Pacific Grove, Monterey Co. (Grinnell 1918) and, leaving the San
Joaquin Valley blank, southward through the Sierra Nevada Mountains and, in
the eastern part of the state, to Death Valley National Park (Grinnell 1937; Bradley
and Deacon 1971). However, Bond (1977) reported a bat much farther south in
eastern San Diego County.

I have identified numerous bats of this species from nearly all counties in the
northern two-thirds of the state, including the counties of Monterey, Kings, Tulare,
and Inyo northward. Unfortunately, relatively few bats of any species were re-
ceived during much of the period under consideration from the counties of San
Luis Obispo, Kern, Santa Barbara, and Imperial, so the absence of silver-haired
bats from those counties is of little significance. However, 23 of the bats were
received from 15 new localities in the southern Californian counties of Los An-
geles, San Bernardino, and San Diego during 1973-1997 (Fig. 4, Appendix). Of
the 23 bats from southern California, seven (identified by L. M. Whitelock) were
discarded before I was able to review and salvage specimens. Thus, voucher
specimens were lost for the following localities ‘in Los Angeles Co.: Bellflower,
Lakewood, and Torrance.

RANGE EXTENSIONS OF BATS IN CALIFORNIA a7

Lasionycteris
noctivagans

| 100 mi.

100 km.

Fig. 4. Known distribution of the silver-haired bat, Lasionycteris noctivagans, in southern Cali-
fornia.

The southernmost California locality for this species on the Pacific coast is San
Diego, represented by a male (MVZ 181863) taken 15 February 1978. San Diego
is 615 km SE of the previously published southernmost Pacific coastal locality at
Pacific Grove (Grinnell 1918) and 84 km WSW of the inland collection site at
Agua Caliente Springs in eastern San Diego Co. (Bond 1977).

Western red bat
Lasiurus blossevillii frantzii (Peters 1871)

This insectivorous, foliage-dwelling, migratory bat, recently regarded as taxo-
nomically separate from the eastern red bat, L. borealis (Baker et al. 1988; Mo-
rales and Bickham 1995), has been reported from southern British Columbia,
Canada, Utah, and western Texas southward through the western United States,
Baja California, mainland Mexico, Nicaragua, and south into South America (Hall
1981; Shump and Shump 1982; Eisenberg 1989; Redford and Eisenberg 1992).

This species generally occurs in California’s central valley, foothills, and in
similar areas of tree growth in southern California, preferring the dense foliage
of trees for shelter, presumably avoiding tree-deficient deserts. Range maps often
depict continuity of distribution through areas of unknown occurrence, although
supportive data are unavailable. Such is true of this species in reference to Cali-
fornian deserts. That limitation may be less misleading in reference to migrants
like the red bat that may seasonally or periodically migrate or stray into or through
these deserts. The following report may represent such an occurrence.

On 21 October 1991, a female western red bat was found crawling on the
ground at the Park Village government housing area near Furnace Creek Ranch,
Death Valley National Park, Inyo Co. External measurements (mm) were: total
length, 116; length of tail, 50; length of ear from notch, 12; length of foot, 7.5;
length of tibia, 21.0; length of forearms, 41.0, 41.5.

This record is within a broad void in the reported distribution of the species.
It is from 183 to 432 km distant from the nearest knowns stations of occurrence:

5 mi SW Fallon, Churchill Co. Nevada (Hall 1946)

58 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Overton, Clark Co., Nevada (Hall 1946)

Mouth of Bright Angel Creek, Grand Canyon National Park, Coconino Co.,
Arizona (Hoffmeister 1986)

Big Sandy Creek, Mohave Co., Arizona (Hoffmeister 1986)

Three Rivers, Tulare Co. (Grinnell 1918)

Lancaster, Los Angeles Co., (based on a discarded female bat identified by L.
M. Whitelock)

Warren’s Ranch, San Bernardino Co., (Grinnell 1918)

Santa Ysabel, San Diego Co. (Grinnell 1918)

Grinnell (1937) suggested that the appearance of hoary bats, Lasiurus cinereus,
and silver-haired bats at Furnace Creek Ranch, Death Valley National Monument,
in spring and fall coincided with their anticipated migratory movements, a con-
clusion that may be applicable as well to the present red bat record. The oasislike
site, surrounded by desert, would be especially attractive to these tree-dwelling
species.

Western yellow bat
Lasiurus xanthinus (Thomas 1897)

Originally described as a subspecies of L. ega, this insectivorous bat recently
was regarded as a separate species (Baker et al. 1988; Morales and Bickham 1995)
whose range reportedly extends southward from southwestern New Mexico,
southern Arizona, and southern California through Baja California, western Mex-
ico and the Mexican plateau to Nuevo Leon and Morelos.

Early locality records of this species in California include:

Palm Springs, Riverside Co. (Constantine 1946)

Cottonwood Spring, Joshua Tree National Monument, Riverside Co. (Loomis
and Stephens 1964)

Pomona, Los Angeles Co. (Stewart 1969)

Borrego Springs, San Diego Co. (Bond 1970)

Fourteen additional localities in the counties of Riverside, San Bernardino, San
Diego, and Imperial were reported later (Constantine et al. 1979). Including the
last-mentioned report, 214 bats of this species were received for identification
after rabies testing during the period 1969-1997. They represented 59 localities
within the aforementioned four counties and from Los Angeles and Orange coun-
ties (Fig. 5, Appendix).

Published northernmost and westernmost Arizona records for this species are
Phoenix, Maricopa Co. (Constantine 1966) and Yuma, Yuma Co. (Constantine
1966), as mapped by Hoffmeister (1986). The present report extends the known
northern and western limits of the range from Phoenix to Los Angeles County as
follows:

Blythe, Riverside Co., 7-XI-1980 (MVZ 181879)

Twentynine Palms, San Bernardino Co., 13-VIII-1980 (MVZ 181943)

Yucca Valley, San Bernardino Co., 25-IX-1985 (MVZ 181946)

Muscoy, San Bernardino Co., 14-I[X-1992 (MVZ 186347)

Azusa, Los Angeles Co., 12-XI-1987 (MVZ 181876)

Glendale, Los Angeles Co., 27-IX-1984 (MVZ 181877).

RANGE EXTENSIONS OF BATS IN CALIFORNIA 59

Lasiurus
xanthinus

100 mi.

200 km.

Fig. 5. Known distribution of the western yellow bat, Lasiurus xanthinus, in California and ad-
jacent Arizona.

Pocketed free-tailed bat
Nyctinomops femorosaccus (Merriam 1889)

Long classified in the genus Tadarida (Shamel 1931), this insectivorous species
recently was placed in the genus Nyctinomops by Freeman (1981). The species
is known from southwestern Texas (Easterla 1973; Schmidley 1991) and southern
New Mexico (Constantine 1958; Findley et al. 1975) through southern Arizona
(Hoffmeister 1986) to southern California and southward in Mexico to Baja Cal-
ifornia, Jalisco, and Nuevo Leon, as mapped by Hall (1981) and by Kumirai and
Jones (1990). In addition to the type locality at Agua Caliente [Palm Springs],
Riverside Co. (Merriam 1889), the species has been reported from only two ad-
ditional California localities, both in San Diego Co.: Palm Canyon, near Borrego
Springs (Neil 1940) and 3 miles southeast of Suncrest, now known as Crest
(Krutzsch 1944, 1945).

I have identified 47 additional bats of this species from 30 localities, 29 of
which are new, from the Californian counties of Imperial, Los Angeles, Orange,
Riverside, San Bernardino, and San Diego (Fig. 6, Appendix). Stations constitut-
ing the northernmost tier of these localities, proceeding from east to west, are:

Calexico, Imperial Co., 3-X-1995 (MVZ 186401)

La Quinta, Riverside Co., 13-IV-1994 (MVZ 186386)

San Bernardino, San Bernardino Co., 15-XI-1985 (MVZ 181965)

Covina, Los Angeles Co., 30-IV-1985 (MVZ 181959)

Inglewood, Los Angeles Co., 18-X-1994 (LACM 94036)

Calexico is located at the Mexico border, 190 km SSW of the nearest Arizona
record at Alamo Crossing, Mohave Co. (Cockrum and Musgrove 1965). Ingle-
wood is 182 km NW of the previously reported westernmost locality at Crest,
San Diego Co.

Big free-tailed bat
Nyctinomops macrotis (Gray 1839)

This insectivorous species is known from British Columbia, Canada, in the
Northwest (Cowan 1945), North Carolina on the Atlantic coast (Di Salvo et al.

60 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Nyctinomops
femorosaccus

oO published
@ new

100 mi.
200 km.

Fig. 6. Known distribution of the pocketed free-tailed bat, Nyctinomops femorosaccus, in Califor-
nia and adjacent Arizona. -

1992), and the central United States southward through most of Mexico, the
Caribbean islands of Cuba, Jamaica, and Hispaniola, and South America to Bo-
livia, northern Argentina, and Uruguay (Hall 1981; Milner et al. 1990). Reports
indicate that its greatest density in the United States is in the Southwest, reports
dwindling northward and eastward. For example, there are no published reports
between San Diego and British Columbia, there are only two reports each from
Oklahoma, Kansas, and Iowa, and no reports between Texas and the single spec-
imen from North Carolina, whereas 36 collection localities for the species were
reported from Arizona, New Mexico, and Texas (Constantine 1958, 1961a, 1961b;
Hoffmeister 1986; Findley et al. 1975; Schmidly 1991).

Four of these bats were reported previously from California. No locality was
given for the first bat (Shamel 1931). The other three were from San Diego, San
Diego Co. (Huey 1932, 1954a; August and Dingman 1973).

The present report concerns 26 additional bats from 25 new localities in the
Californian counties of Contra Costa, Imperial, Los Angeles, Orange, Riverside,
San Bernardino, San Diego, San Luis Obispo, San Mateo, and Santa Barbara (Fig.
7, Appendix). Only the northermost localities are listed below, proceeding from
east to west:

El Centro, Imperial Co., 31-II]-1982 (MVZ 181981)

Palm Springs, Riverside Co., 4-IV-1994 (MVZ 181986)

Pomona, Los Angeles Co., 23-XI-1987 (MVZ 181985)

Azusa, Los Angeles Co., 2-X-1997 (LACM 94037)

Burbank, Los Angeles Co., 19-XI-1987 (MVZ 181982)

Santa Barbara, Santa Barbara Co., 27-XI-1996 (MVZ 186402)

Morro Bay, San Luis Obispo Co., 18-XII-1981 (MVZ 181992)

Pacifica, San Mateo Co., 3-I-1984 (MVZ 181993)

Martinez, Contra Costa Co., 13-XI-1979 (MVZ 181980)

El Centro is 200-302 km distant from the nearest published reports to the east
at Eagle Tank, Yuma Co., Arizona (Simmons 1966); 1.5 mi SE Kingman, Mohave
Co., Arizona (Cockrum et al. 1996); Henderson, Clark Co., Nevada (Bradley et
al. 1965). Martinez is 1279 km S of Essondale, British Columbia, the northern-
most published locality. Relatively few bats of any species routinely are tested

RANGE EXTENSIONS OF BATS IN CALIFORNIA 61

Nyctinomops
macrotis

Oo published
@ new

Fig. 7. Known distribution of the big free-tailed bat, Nyctinomops macrotis, in California and
adjacent Nevada.

for rabies in Californian coastal counties north of the vicinity of San Francisco,
rendering nearly meaningless the absence of specimens of this rare bat from those
counties.

Western mastiff bat
Eumops perotis californicus (Merriam 1890)

This insectivorous subspecies has been reported from California to Texas south-
ward to at least central Mexico, whereas other subspecies are recorded from north-
ern South America southward into Argentina, (Koopman 1978). The species is
also known from Cuba (Koopman 1993).

Eighty-six mastiff bats were received from laboratories between 1973 and late
1997. Forty-nine new California locality records from 13 counties resulted, which
with 38 published records, are presented in Fig. 8 and the appendix. The new
records generally fill voids in the known range but include the northermost lo-
cality. This species has been reported earlier at or near the Colorado River from
Yuma, Yuma Co., Arizona (Cockrum 1960); 38.6 km S of Palo Verde, Imperial
Co. (Eger 1977); Parker, La Paz Co., Arizona (Sanborn 1932); and Las Vegas,
Clark Co., Nevada (Bradley and O’Farrell 1967). However, it has not been re-

62 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Eumops perotis

a a |
200 km.

Fig. 8. Known distribution of the western mastiff bat, Eumops perotis californicus, in California
and adjacent border areas.

ported heretofore from the Imperial Valley, Imperial Co., the Coachella Valley
north of Mecca, Riverside Co. (Grinnell 1918), from elsewhere in Riverside Co.
except 4 mi SW of Lakeview (Vaughan 1959), from San Bernardino Co. except
Colton (Grinnell 1918; Howell 1920a) and Keys Ranch (Campbell 1931), which
apparently was a sight record.

Counties represented herein from which no published records exist are Ventura,
Santa Barbara, Merced, Stanislaus, and San Joaquin.

The Calexico locality (MVZ 186385) is about 33 km WNW the nearest Mex-
ican locality record at Cerro Prieto, Baja California (MVZ 110877, a skull col-
lected by S. B. Benson 19 April 1948), the only record of this species in Baja
California.

The El Mirage, San Bernardino Co. bat (MVZ 186400) is the first specimen
from the western Mojave Desert north of the transverse San Gabriel and San
Bernardino Mountain Ranges, although Vaughan (1959) reported hearing the char-
acteristic high-pitched, piercing calls of this species in the same general area.

The Durham, Butte Co. bat, a female (MVZ 186399) taken 27 February 1997,
represents the northernmost specimen-substantiated locality for this species. Only
25.6 km NW of Oroville, the previous northernmost locality (Eger 1977), Durham

RANGE EXTENSIONS OF BATS IN CALIFORNIA 63

is 692 km WNW of Las Vegas, the next northernmost locality, and 952 km NW
of Calexico.

Discussion

The samples of bats from which these locality records were derived were char-
acterized by numerous biases that varied in space and time. In general, the bats
were dead, disabled through injury or disease, or very young when discovered,
and the majority had been brought home by household cats. Categorized as rabies-
suspect, they were tested for that infection, especially if people or pets had been
bitten or otherwise exposed.

Numbers of bats tested were proportional to the human population that discov-
ered them, so many were from cities and towns, whereas few were from unpop-
ulated areas. Most counties sent for taxonomic identification all of the bats they
tested, but others sent bats intermittently if at all, a few counties sending only
some of the bats that had proved to be infected. Relevant news stories temporarily
increased public awareness and submissions for testing, and molestation of col-
onies or illegal poisoning of bats had the same effect due to consequent increased
human and pet contacts.

The surprisingly great range extensions indicated for M. velifer and L. curasoae
at first elicited thoughts that the bats may have been accidently transported by
truck or other vehicle in which they had temporarily taken shelter and been closed
inside. However, such possibilities seemed unlikely after the second and third
velifer were found and after consideration that other southerly species (e.g., C.
mexicana, M. californicus, and L. xanthinus) are now known or were recently
known in the same general southern California areas.

Whether all of the reported range extensions from more southerly population
centers reflect true changes or our emergence from a less-informed state is unclear.
The increase in sampling of bats subsequent to the discovery of bat rabies in the
United States in 1953 and the ever-increasing human and cat populations to collect
them are undeniable. However, as evident are factors that support a concept of
invasion. Lasiurus xanthinus is now relatively common in much of southern Cal-
ifornia, where it was undetected until 1945. That species typically lives in fan
palms, with which human habitat in California has become increasingly forested
for ornamental purposes, evidently encouraging this bat’s range expansion from
the occasional desert oasis where fan palms naturally grow in California. The
majority of the migratory nectar-drinking bats (Choeronycteris and Leptonycteris)
reported herein were males found during fall, corresponding to the comparable
range-expansion scenario typically observed in pioneering birds, especially mi-
gratory species (Johnson 1994). Myotis v. velifer appears to be migratory as well,
because it has been unknown during cold months along the Colorado River and
in most of Arizona. Perhaps overriding influences effecting these perceived range
expansions of bats from the south and southeast are climatic warming and in-
creased summer moisture, as hypothesized by Johnson (1994) in reference to
perceived avian range expansions.

Six of the 10 species of bat dealt with herein are on the State of California
Department of Fish and Game’s List of Mammal Species of Special Concern: M.
californicus, C. mexicana, M. velifer, N. femorosaccus, N. macrotis, and E. per-
otis. A seventh, L. blossevillii, is expected to be added, and an eighth, L. curasoae,

64 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

will probably be included after its presence in California is anounced herein. Of
these eight species, M. californicus, C. mexicana, L. curasoae, and M. velifer are
generally found in caves or mines. Caves are relatively few in California, and far
fewer are suitably warm for these bats. Most are visited by recreational hikers,
and human population encroachment on them is increasing. The widespread clos-
ing of unused mine tunnels and shafts during hazard abatement programs, the
destruction of entire mine-riddled mountains by heap-leach mining practices, and
the establishment of toxic ponds and runoff by the latter must contribute to the
loss and future extinction of these and other associated species of wildlife in
California.

Nyctinomops femorosaccus, N. macrotis, and E. perotis naturally live in crev-
ices in cliffs or in spacious caves, but they sometimes live in suitably high human
structures, such as older wooden buildings, most of which have been replaced by
unsuitable substitutes. Like most other bats, these molossids have suffered as
targets of exterminators, especially Eumops, the largest and more obvious of the
three.

Increasing destruction of old-growth forest is removing the attendant hollows
and loose bark crevices used as shelter by L. noctivagans, a species also adversely
affected by the increasing elimination of native forested riparian habitat, the tree
foliage of which provides shelter for L. blossevillii.

The distributional data reported herein represent only one of several advantages
consequent to identifying to species the bats tested for rabies in California or
elsewhere. Taxonomic criteria, delineated through the past and continuing work
of scientists in field, museum, university, or laboratory, find increasing application
in disentangling the epidemiologic web of each disease that escapes from natural
ecosystems into invading human populations, and rabies is no exception. Despite
early opinions of leading health authorities that determining the species of each
rabid bat was superfluous and that there existed only a single natural strain of
rabies virus, it is now acknowledged that each of various known natural host
species of bat or carnivore may be afflicted by one or sometimes more strains of
rabies virus specific to that species. Host species-specific rabies virus strains were
first recognized by differences in either susceptibility or in pathological reactions
to the strains following inoculations of virus into panels of other mammal species
(Constantine 1967a), later by monoclonal antibody techniques (Smith et al. 1986;
Rupprecht et al. 1987), and recently by nucleotide sequence analysis of the viral
nucleoprotein genome (Smith 1996). It is evident that a factual, comprehensive
awareness of this and other zoonosis problems, now better known through the
contributions of vertebrate, invertebrate, and virus taxonomists, will precede man-
kind’s ability to develop appropriate responses. Thus, other states are encouraged
to utilize the services of professional taxonomists to salvage valuable data and
voucher specimens of bats currently being discarded after rabies tests.

Acknowledgments

I am indebted to many local, county, and state personnel who have and continue
to support the effort to identify the bats that have been tested for rabies in Cali-
fornia. Although participants include animal and vector control personnel, sani-
tarians, public health investigators and others, my contacts have been with health
department directors, physicians, public health veterinarians, and especially lab-

RANGE EXTENSIONS OF BATS IN CALIFORNIA 65

oratory directors, microbiologists, and laboratory assistants who have shared the
unpleasant work of organizing, labeling, and packaging for shipment the usually
decayed and often mangled carcasses. Thus, my records lack the names of many
participants but represent primarily laboratory personnel, as follows: E. Aaron,
A. Adams, R. Alexander, O. Armstrong, M. Ascher, B. Austin, R. Avedian, A.
Back, L. Barkley, R. Barnes, L. Barrett, I. Bihl, Jr., M. Brashear, J. Bunter, A.
Chandler, J. Cleaves, S. Coffey, D. Cottam, G. Cookson, M. Croghan, R. Crosby,
T. E Cuculich, H. DeBoer, D. Dondero, L. Doughty, J. Earnst, C. Egan, H. B.
Ehrhard, R. W. Emmons, J. Falcon, D. Ferrero, P Flanders, B. Fleischer, K. Flink,
C. Flinn, W. Fontes, B. Freeman, B. Fujikawa, EK Gettman, M. Giles, D. Gillies,
R. Greenwood, W. Gregory, G. Guibert, M. Hansen, H. Hanson, K. V. Hardy, M.
Hartley, S. Harvey, T. P. Herbenick, D. Hird, N. Hirada, M. T. Holland, J. Horn-
stein, E. Howard, S. Hull, G. L. Humphrey, R. R. Jackson, H. Johnstone, H. N.
Johnson, S. Kaddas, G. H. Kellogg, N. S. Kelly, R. Koelewyn, S. Kwan, R.
Lasater, W. Lawrence, E. H. Lennette, S. Liska, D. Lockford, K. S. Mahoney, J.
Marron, M. J. Martins, S. Matson, W. H. McCarley, D. McFarlane, T. Meier, D.
V. Miller, L. N. Miller, M. Miller, D. Moore, B. Mognus, K. EK Murray, D. Murrill,
M. Nachtigal, L. Oliver, W. Ota, D. Perez, C. A. Peter, J. Peterson, E. D. Pierson,
E. Portoli, A. Pruitt, R. Purves, W. E. Rainey, K. Riley, W. L. Rottman, R. Ruiz,
J. Ruprecht, C. P. Ryan, J. Saunders, M. Schaffran, R. J. Schroeder, H. Serva, R.
Shamansky, R. E Smith, K. E. Stager, S. Stanfield, Y. Sugiyama, J. Tacal, D.
Taclindo, K. Takata, R. Talbot, M. A. Thompson, R. Trump, J. Voss, H. Wallace,
E. K. Weeks, L. M. Whitelock, J. Wilbur, B. Wilcke, Jr, M. Wiles, S. A. Willis,
J. Woodie, P. Wong, M. Yamashiro, D. Yong, and C. Young. J. L. Patton and M.
A. Bogan are particularly thanked for reviewing and improving the manuscript.
Special appreciation is due Karen Klitz, who prepared the final maps.

Literature Cited

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G2:

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Accepted for publication 13 November 1997

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Bull. Southern California Acad. Sci.
97(2), 1998, pp. 76-81
© Southern California Academy of Sciences, 1998

Strategies of Predator Attacks on the Schooling Fish,
Selar crumenophthalmus, in Academy Bay, Socorro Island,
Islas Revillagigedo, Mexico

Bayard H. Brattstrom
Department of Biology, California State University, Fullerton, CA 92634-9480

Abstract.—One of the main reasons that fish form schools is that it serves to
reduce the risk of being eaten. Single predators are most successful at capturing
individuals not in schools. For every successful anti-predator strategy by a prey
species there is usually a concomitant more successful strategy by the predators.
I report here on the behavior of three species of predatory fish and two species
of predatory birds toward a school of jacks, Selar crumenophthalmus which dem-
onstrate that these predators use a variety of methods to obtain fish from a school.

Fish school for a variety of reasons. The behavior, dynamics, and advantages
of fish schools and other similar aggregations in birds, tadpoles, and mammals
have been fully described by many authors (Brattstrom 1962, 1989; Breder 1959,
1967; Cushing and Harden Jones 1968; Elliott, et al. 1977; Hamilton 1971; Major
1978, 1979; Partridge 1982; Partridge and Pitcher 1980; Seghers 1974; Shaw
1970, 1978; Webb 1980). One of the main reasons that fish school is that it serves
to reduce the risk of being eaten (Breder 1967; Partridge 1982). Single predators
are most successful at capturing isolated, individual prey and less successful at
capturing individuals in schools (Brattstrom 1989; Major 1978, 1979). Thanks to
natural selection, there usually will be a concomitant more successful strategy by
the predators for every successful anti-predator strategy by a prey species! Studies
on the behavior of the predator in response to schooling fish are diverse (Katzir
and Chamhi 1993; Major 1978, 1979; Parish, Strand, and Lott 1989; Schmitt and
Strand 1982). The outcome of any interaction between the predator and the prey
fish usually depends on three factors: relative performance, maneuvering, and
timing (Webb 1980). In addition, Major (1978) showed that while single predators
are most successful at capturing isolated prey and less successful at capturing
individuals in schools, grouped predators were more successful at capturing
schooled prey. Larger predators were also able to break up schools of prey, re-
sulting in increased numbers of prey becoming isolated. These predators then
attacked these isolated individuals (Major 1978). I report here on the behavior of
three species of predatory fish and two species of predatory birds preying on a
school of jacks, Selar crumenophthalmus. This behavior shows that these preda-
tors have developed diverse strategies to prey on schooling fish.

I observed the predation of three species of fish yellowtail, Seriola lalanderi,
California needlefish, Strongylura exilis, and black-tipped shark, Carcharhinus
limbatus) and two species of birds (masked booby, Sula dactylatra, and great
frigatebird, Fregata minor) on schooling jacks, Selar crumenophthalmus, locally
called cabalito.

PREDATORS ON FISH SCHOOLS We.

LAVA FLOW ms

MIDDLE BEACH

Fig. 1. Diagram of Academy Bay, Socorro Island, Mexico of cliff from which observations were

made.

Observations were made from a cliff above Academy Bay, at the north end of
Socorro Island, Islas Revillagigedo, Mexico. Socorro Island is 390 km SW of the
southern tip of Baja California (see descriptions in Brattstrom 1955, 1963, 1982,
1990; Brattstrom and Howell 1956; Richards and Brattstrom 1959).

Observations were made throughout the day of 14 April, 1978 by me and other
members of the Carnegie Museum/Sea World, 1978 Expedition to the Islas Re-
villagigedo. Notes and photographs (35 mm slides, 16 mm color film) were made
of the schooling jacks (Fig. 1, 3). Predation by the fish was observed in the clear
shallow water from the cliff (Fig. 1), predation by the birds was observed from
the cliff, beach, and aboard the expedition ship anchored in Academy Bay. The
temperature of the water in the bay as taken from under the ship was 25°C.

Following Breder (1959), I define a school as a behavior in which the fish are
oriented in the same direction and are more or less one fish-length apart, a Pod
as a group of fish that are in contact, a Pod I (or “‘ball’’) when the fish show no
orientation and a Pod II when the fish show orientation.

The jacks were in two, large schools (Fig. 1), each estimated to contain tens
of thousands of fish. These schools would often spontaneously change into a Pod
I or Pod II. Even when the fish were oriented in one direction, the entire school
or pod did not really move very far. Instead, the entire school or pod seemed to
slowly ‘‘float’’ about the bay. School B (see Fig. 1) once divided in two and then
recombined. The two main schools never joined, even though at one time they
were within 3 m of each other.

78 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

The behavior of the fish in the school changed as the school approached the
shore (Fig. 2; beach effect). Here the waves and/or the shallow water caused the
fish nearest the shore to form a Pod II (dots in Fig. 2). This pod formation spread
until the whole group was in a pod. This pod slowly moved away from the shore
and switched back to a school.

Three species of predatory fish were also observed in the bay and each at-
tempted to feed on the jacks in a different way. Groups of from two to 12 yel-
lowtail swam around the bay always some distance from the jacks. They would
circle both schools or swim back and forth in front of the beach or below the
cliff. Now and then, and very suddenly, the group would turn toward the school
and swim side by side straight into the school of jacks (Fig. 2, top). The fish in
the school would immediately form a Pod I or Pod II at the edge of the school
where the yellowtail were attacking. With the continued forward movement of
the yellowtail, a ripple-like effect of school changing into pod occurred until
finally all the fish were in a ball or Pod I. As the predators left, the pod would
change back into a school formation as diagrammed in Fig. 2. I could not deter-
mine if the yellowtail actually caught any of the jacks, though this strategy is
usually successful (Major 1978). Cooperative foraging in yellowtail has also been
documented by Schmitt and Strand (1982).

Two black-tip sharks were also swimming in the bay. Now and then a shark
would circle around a school of jacks, moving closer and closer to the school as
it circled (Fig. 2). When the shark was about 3 m from the school, the jacks on
the outer edge of the school would begin to contact each other. As the shark got
closer the pod formation continued from outside toward the center until all fish
were in a Pod I or ball. At that time the shark turned directly into the ball, mouth
opening and closing (Fig. 2).

A single needlefish also occurred in the bay. It usually swam just below the
tall cliff on which I was standing. It appeared not to notice the schooling fish,
yet (and I saw this happen many times) the needlefish would turn, suddenly,
directly toward the school. It swam fast, and just before reaching the school,
would jump out of the water and almost sail, like a flying fish. It would land in
the water in the middle of the schooling jacks with its mouth opening and closing
(Fig. 2). Again, I could not determine if the needlefish was successful in obtaining
a prey fish, but the density of jacks would suggest that there was a high degree
of success.

The schooling jacks were also preyed upon by two sea birds. For most of the
day a single frigatebird and a single masked booby flew over the bay. Both fed
on the jacks by plunging down on the fish from above (Fig. 2). Both birds were
successful in catching fish. The booby, for example, caught three fish in three
dives over a six minute period from 1432-1458 hrs. The school/pod concentration
of the prey made escape responses of the fish less effective (Katzir and Camhi
1993) and presumably therefore increased the success of the birds.

While schooling behavior in fishes may have many causes and advantages, the
most documented advantage is, of course, the group effect against predators
(Breder 1967; Partridge 1982). It is usually the individual, isolated or separated
from the herd, flock, or school, that is taken by predators (Brattstrom 1989). Yet
the mere presence of this school in this bay allowed the feeding on the school by
these predators. In addition, two of the predators manipulated the school into a

PREDATORS ON FISH SCHOOLS

‘UONVULIOJ pod & OJUI SUISURYS SI [OOYSS dy} DIDYM PUL UDYM dJBdIPUT SJOP YORI ‘;OOYds dy) JO 9zIs pue adeys ay) smoys
SUIPINO Ie[NSILy “yoeRoq ay} 0} syoef oy} JO asuodsoa1 puv ‘sJOJeposd asoy) 0} syoef oy) JO asuOdsa ‘s1OJepoid [VIDADS JO JOIARYOQ SUIMOYS SUILISVIGQ “7 ‘SI

HOV3d
SNIAVST q—
Od

Guid 31Vv9Id4a GNV ASOOd

Ov;

HSI4d 31034N

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aod es

1034343 HOVW3a
WIVLILV AWYVHS NOILVWHO4 GOd 100HOS

HLIM GOd ~ L * / ~

oN "4
&, NS HICE

1OOHIS ——— GOd
SHOLVG3Hd ON NOILYVWYO4 GOd 1OOHIS

CO @ cG2@: eC

STIVIMOTI3A

80 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Fig. 3. Photograph of a school of jacks, Selar crumenophthalmus, in Academy Bay, Socorro Island,
Mexico. Photograph by Robert Pitman.

pod formation where it would be expected that nearly any bite by a predator
would be assured of striking a fish. Parrish, Strand, and Lott (1989) showed that
while predation was highest on isolated stragglers, predation on a school of flat-
iron herring, Harengula thrissina, due to predator strategies, was about equal on
peripheral and central fish in the school. Thus, while there is an advantage to
schooling by fish, there are also predators that take advantage of that schooling
behavior. In addition, cooperative hunting can circumvent the schooling advantage
to prey species (Schmitt and Strand 1982).

Acknowledgments

The 1978 trip to the Islas Revillagigedo was aboard the R/V Sea World and
was sponsored by the Carnegie Museum of Philadelphia and Sea World of San
Diego under the leadership of Drs. Kenneth Parkes and Joe Jehl and was specif-
ically designed to study aspects of the biota of Socorro and allow me to continue
my studies of the effect of Barcena Volcano, 1952 on the biota of San Benedicto
Island (Brattstrom 1963). I am very thankful to those gentlemen and their insti-
tutions for support. Identifications of fish were made by Dr. Richard Rosenblatt,
Scripps Institution of Oceanography and an early draft of the manuscript was read
by Dr. Michael Horn. Figure 1 was photographed by Robert Pitman and the copy
made by Alan Fugleberg. The drawings were made by Mark Zolle with funds
from the Department of Biology, California State University, Fullerton.

PREDATORS ON FISH SCHOOLS 81

Literature Cited

Brattstrom, B. H. 1955. Notes on the herpetology of the Revillagigedo Islands, Mexico. Am. Mid.
Nat. 54:219-—229.
. 1962. Thermal control of aggregation behavior in tadpoles. Herpetologica. 18:38—46.

1963. Barcena Volcano, 1952; its effect on the fauna and flora of San Benedicto Island,
Mexico. Pp. 499-524. In Pacific Basin Biogeography. (J. L. Grissett, ed.), Bishop Museum
Press:

. 1982. The comparison of the social behavior of Chelonia mydas on the Islas Revillagigedo,

Mexico. Herp: Rev: 13:71:

. 1989. Predation of Bald Eagles, Habaeetus leucocephalus, on American Coots, Fulca Amer-

icana. J. Raptor Research, 23:16—17.

. 1990. Biogeography of the Islas Revillagigedo, Mexico, J. Biogeogr. 17:177-183.

, Brattstrom, B. H., and T. R. Howell. 1956. The birds of the Revillagigedo Islands, Mexico.
Condor 59:107—120.

Breder, C. M. Jr. 1959. Studies on social groupings in fishes. Bull. Amer. Mus. Nat. Hist. 117:393-
482.

. 1967. On the survival value of fish schools. Zoologica 52:25—40.

Cushing, D. H., and EF R. Harden Jones. 1968. Why do fish school? Nature 218:918—920.

Elliott, J. P, I. McTaggart-Cowan, and C. S. Holling. 1977. Prey capture by the African Lion. Ca-
nadian J. Zool. 55:1811—1828.

Hamilton, W. D. 1971. Geometry for the selfish herd. J. Theor. Biol. 31:142—-159.

Katzir, G., and J. M. Camhi. 1993. Escape response of Black Mollies (Poecilia sphenop) to predatory
dives of a Pied Kingfisher (Ceryle rudis). Copeia 1993:549-553.

Major, P. EF 1978. Predator-prey interactions in two schooling fishes, Caranx ignobilis and Stolephorus
purpureus. Anim. Beh. 26:760—777.

. 1979. Piscivorous predators and disabled prey. Copeia 1979:158.

Parrish, J. K., S. W. Strand, and J. L. Lott. 1989. Predation on a school of Flat-iron Herring, Harengula
thrissima Copeia 1989:1089.

Partridge, B. L. 1982. The structure and function of fish schools. Sci. Amer. 1982:114—123.

Partridge, B. L., and T. J. Pitcher. 1980. The sensory basis of fish schools. J. Comp. Physiol. 135:
315-325.

Richards, A. F, and B. H. Brattstrom. 1959. Bibliography, cartography, discovery, and exploration
of the Islas Revillagigedo. Proc. Calif. Acad. Sci. Ser 4. 20:315-—360.

Schmitt, R. J., and S. W. Strand. 1982. Cooperative foraging by yellowtail, Seriola lalandei (Caran-
gidae) on two species of fish prey. Copeia 1982:714—717.

Seghers, B. H. 1974. Schooling behavior in the guppy (Poecilia reticulata): an evolutionary response
to predation. Evolution 28:486—488.

Shaw, E. 1962. The Schooling of fishes: Sci Amer. June 1—10.

. 1970. Schooling in fishes: Critique and review. in Aronson, L. R., E. Tobach, D. S. Lehrman,

and J. Rosenblatt (eds.), Development and Evolution of behavior: essays in memory of T. G.

Schneirla. W. H. Freeman Co. San Francisco.

. 1978. Schooling of fishes. Amer. Sci. 66:166—175.

Webb, P. W. 1980. Does schooling reduce fast-start response latencies in teleosts. Comp. Biochem.
Physiol. 652A:231—234.

Accepted for publication, 26 June, 1997.

Bull. Southern California Acad. Sci.
97(2), 1998, pp. 82-85
© Southern California Academy of Sciences, 1998

Composition of the Helminth Community of a Montane Population
of the Coastal Whiptail, Cnemidophorus tigris multiscutatus
(Sauria: Teiidae) from Los Angeles County, California

Stephen R. Goldberg,' Charles R. Bursey,” and Mei Q. Wu!

'Department of Biology, Whittier College, Whittier, California 90608
*Department of Biology, Pennsylvania State University, Shenango Campus,
147 Shenango Avenue, Sharon, Pennsylvania 16146

Abstract.—Two-hundred sixty two Cnemidophorus tigris multiscutatus from the
San Gabriel Mountains of Southern California were examined for helminths. The
helminth community consisted of two species of cestodes (Oochoristica scelopori
and Mesocestoides sp.), two species of nematodes (Pharyngodon cnemidophori
and Physaloptera sp.) and one species of acanthocephalan (Moniliformis monili-
formis). The helminth with highest prevalence (15%) and greatest mean intensity
(6.35) was Pharyngodon cnemidophori. Cnemidophorus tigris represents a new
host record for Oochoristca scelopori and Moniliformis moniliformis.

The western whiptail, Cnemidophorus tigris Baird and Girard, 1852 ranges
from north central Oregon and southern Idaho, south to Baja California and south-
ern Coahuila, México and east to western Colorado, New Mexico and west Texas
(Stebbins 1985). There are reports of helminths from C. tigris from Arizona (Ba-
bero and Matthias 1967; Benes 1985; Goldberg et al. 1997), California (Read and
Amrein 1953; Telford 1970; Mankau and Widmer 1977), Idaho (Lyon 1986),
Nevada (Babero and Matthias 1967), Texas (Specian and Ubelaker 1974a, b) and
Utah (Grundmann 1959). The purpose of this paper is to report on the composition
of the helminth community from a montane population of a subspecies of C.
tigris, namely, the coastal whiptail, C. tigris multiscutatus Cope, 1892, from the
San Gabriel Mountains of Los Angeles County, California. There are no previous
reports of helminths from this subspecies which occurs in coastal California and
Baja California (Stebbins 1985). Additionally, comparisons are made with hel-
minth communities in other populations of C. figris.

Materials and Methods

Two-hundred sixty two Cnemidophorus tigris multiscutatus from the San Ga-
briel Mountains, Los Angeles Co., California were examined for helminths. Two
sites were sampled: 198 (112 female, 86 male) lizards were collected along Cal-
ifornia Highway 39 at 1580 m elevation and 64 (31 female, 33 male) from along
California Highway 2 at 1830 m elevation. These specimens were collected in
1971 and 1974 by shooting with 22-caliber dust shot, fixed in 10% formalin and
stored in ethanol. They were deposited in the Natural History Museum of Los
Angeles County (LACM 111193-110931).

The body cavity was opened by a longitudinal incision from vent to throat,
and the digestive tract was removed by cutting across the anterior esophagus and
rectum. The lumen of the esophagus, stomach, small and large intestines and the

HELMINTH COMMUNITY OF THE COASTAL WHIPTAIL 83

Table 1. Helminths from 262 Cnemidophorus tigris multiscutatus from the San Gabriel Mountains,
Los Angeles County, California (collected 1971 and 1974).

Preva- Mean
Number Infected lence! abun-
Helminth species helminths — lizards (%) dance? Site
Cestoda
Mesocestoides sp. (Tetrathyridia) 388 3 l 1.48 Body cavity
Oochoristica scelopori 6 5 2 0.02 Small intestine
Nematoda
Pharyngodon cnemidophori 1663 38 15 6.35 Large intestine
Physaloptera sp. (larvae) 6 3 1 0.02 Stomach
Acanthocephala
Moniliformis moniliformis 9 3 l 0.03 Small intestine

' Number of hosts infected with one or more individuals of a parasite species divided by the number
of hosts examined.
? Total number of individuals of a parasite species divided by the total number of hosts examined.

surfaces of the liver and body cavity were examined for helminths. Each helminth
was initially placed in a drop of glycerol on a glass slide. Nematodes were iden-
tified from these temporary mounts. Cestodes and acanthocephalans were stained
with hematoxylin and identified. Terminology usage is in accordance with Bush
et al. (1997). Selected specimens were deposited in the U.S. National Parasite
Collection, USNPC, Beltsville, Maryland: Mesocestoides sp. (87530); Oochoris-
tica scelopori (87529); Pharyngodon cnemidophori (87531); Physaloptera sp. lar-
vae (87532); Moniliformis moniliformis (87533).

Results

The helminth community of the San Gabriel Mountain population of C. t.
multiscutatus was found to consist of two species of cestodes, Oochoristica sce-
lopori Voge and Fox 1950 and Mesocestoides sp. (tetrathyridea only), two species
of nematodes, Pharyngodon cnemidophori Read and Amrein 1953 and Physalop-
tera sp. (3rd stage larvae), and one species of acanthocephalan, Moniliformis
moniliformis (Bremser 1811). The number of helminths, number of infected liz-
ards, prevalence, mean abundance and site of infection are given in Table 1. At
1530 m elevation, (18%) 35 of 198 lizards harbored helminths, at 1580 m, (14%)
9 of 64; there was no significant difference for prevalence of helminths between
elevations (chi-square = 0.33, | df, P > 0.05). Likewise, no significant difference
was found between prevalence of helminths between female, (18%) 26 of 143
infected, and male, (15%) 18 of 119, lizards (chi-square = 0.31, 1 df, P > 0.05).
It should be noted, however, that the nine Moniliformis moniliformis were found
only at 1530 m elevation; one female and two male lizards were infected. The
occurrence of Oochoristica scelopori and Moniliformis moniliformis represent
new parasite records for Cnemidophorus tigris.

Discussion

In the present study, C. t. multiscutatus served as a paratenic host for three of
the five species of helminths found. These species were represented by juvenile
forms only; tetrathyridia of Mesocestoides sp., 3rd stage Physaloptera sp., and
juvenile Moniliformis moniliformis. Tetrathyridia of Mesocestoides sp. are known

SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Table 2. Helminth communities (species reaching maturity) of Cnemidophorus tigris.

Locality

Arizona, Maricopa County

Arizona, Mohave County
Arizona, Pima County

Reference

Benes 1985

Babero and Matthias 1967
Goldberg et al. 1997

Helminth community

Oochoristica sp.

Alaeuris sp.
Pharyngodon warneri
Oochoristica bivitellobata

Abbreviata terrapenis

Pharyngodon warneri
California, Los Angeles County this paper Oochoristica scelopori
Pharyngodon cnemidophori
Oochoristica bivitellobata
Pharyngodon cnemidophori
Skrjabinoptera phrynosoma
Thubunaea iguanae
Pharyngodon cnemidophori
Oochoristica bivitellobata
Oochoristica bivitellobata
Thubunaea cnemidophorus
Parathelandors texanus
Pharyngodon cnemidophori
Oochoristica bivitellobata

Pharyngodon warneri

California, Riverside County Telford 1970

California, San Bernardino County Read and Amrein 1953
Idaho : Lyon 1986
Nevada, Clark County Babero and Matthias 1967

Specian and Ubelaker 1974a
Specian and Ubelaker 1974b
Utah Grundmann 1959

Texas, Brewster County

from a large number of lizard species (see McAllister 1988) and have previously
been reported from C. tigris from California (Mankau and Widmer 1977), Arizona
(Benes 1985) and Nevada (Babero and Matthias 1967). Mesocestoides sp. is
thought to require an arthropod intermediate host (Webster 1949). Third stage
larvae of Physaloptera sp. are commonly found in species of Cnemidophorus (see
Goldberg et al. 1993). In North America, no species of Cnemidophorus is known
to harbor adult Physaloptera. Helminths (USNPC # 80202) identified as Physa-
loptera retusa in the report by Goldberg and Bursey (1989) were found to be
Abbreviata terrapenis. Arthropods serve as intermediate hosts (Lincoln and An-
derson 1975). Mammals, especially rodents, serve as definitive hosts for M. mo-
niliformis; insects are intermediate hosts (Van Cleave 1953). Unidentified acan-
thocephalans were reported in C. tigris from central Arizona by Benes (1985) and
Centrorhynchus sp. was found in C. tigris from southern Arizona by Goldberg et
al. (1997). These helminth species might be expected in any insectivore. Cne-
midophorus tigris also serves as a paratenic host for another nematode, Angus-
ticaecum sp. from Utah (Grundmann 1959).

Cnemidophorus t. multiscutatus served as definitive hosts for two of the five
species of helminths found: Oochoristica scelopori and Pharyngodon cnemido-
phori. Oochoristica scelopori is known from a variety of North American lizards
(see Goldberg et al. 1996). Pharyngodon cnemidophori has been reported only
from teiid lizards: C. tigris in Texas (Specian and Ubelaker 1974b); C. tigris in
California (as Cnemidophorus tesselatus in Read and Amrein 1953; Telford 1970).
Other helminths for which C. tigris serves as a definitive host are Oochoristica
bivitellobata, Abbreviata terrapenis, Pharyngodon warneri, Parathelandros tex-
anus, Skrjabinoptera phrynosoma, Thubunaea cnemidophorus and T. iguanae (Ta-
ble 2). Cnemidophorus tigris from central Arizona was reported to harbor Alaeuris

HELMINTH COMMUNITY OF THE COASTAL WHIPTAIL 85

sp. and Oochoristica sp. by Benes (1985). We believe the identification of Alaeu-
ris sp. to be incorrect and consider this instance to represent an oxyurid species,
probably Pharyngodon sp. It is of interest to note that the helminth community
for which C. tigris is definitive host is different in each population so far studied
(Table 2). This suggests that distribution patterns of helminth species are often
different from distribution patterns of hosts or potential hosts.

Acknowledgments

We thank Robert L. Bezy (Natural History Museum of Los Angeles County)
for permission to examine Cnemidophorus tigris multiscutatus for helminths.

Literature Cited

Babero, B. B., and D. Matthias. 1967. Thubunaea cnemidophorus n. sp., and other helminths from
lizards, Cnemidophorus tigris, in Nevada and Arizona. Trans. Amer. Microsc. Soc., 86:173—
AT

Benes, E. S. 1985. Helminth parasitism in some central Arizona lizards. Southwest. Nat., 30:467—
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Bush, A. O., K. D. Lafferty. J. M. Lotz and A. W. Shostak. 1997. Parasitology meets ecology on its
own terms: Margolis et al. revisited. J. Parasitol., 83:575-583.

Goldberg, S. R., and C. R. Bursey. 1989. Helminths of the giant spotted whiptail, Cnemidophorus
burti stictogrammus (Sauria: Teiidae). Proc. Helminthol. Soc. Wash., 56:86—87.

, and H. Cheam. 1997. Helminths from the Sonoran spotted whiptail, Cnemidophorus

sonorae, and the western whiptail, Cnemidophorus tigris (Sauria: Teiidae), from southern Ar-

izona with comments on Abbreviata terrapenis (Nematoda: Physalopteridae). Great Basin Nat.,

SOS OAM

; , C. T. McAllister, H. M. Smith and Q. A. Truong. 1996. Oochoristica scelopori

(Cestoda: Linstowiidae) in a grassland population of the bunch grass lizard, Sceloporus scalaris

(Phrynosomatidae), from Arizona. Great Basin Nat., 56:180-—182.

, and R. Tawil. 1993. Gastrointestinal helminths of the western brush lizard, Urosau-
rus graciosus graciosus (Phrynosomatidae). Bull. So. Cal. Acad. Sci., 92:43-51.

Grundmann, A. W. 1959. Parasites recovered from six species of Utah lizards. J. Parasitol., 45:394.

Lincoln, R. C., and R. C. Anderson. 1975. Development of Physaloptera maxillaris (Nematoda) in
the common field cricket (Gryllus pennsylvanicus). Can. J. Zool., 53:385—390.

Lyon, R. E. 1986. Helminth parasites of six lizard species from southern Idaho. Proc. Helm. Soc.
Wash., 53:291-293.

Mankau, S. K., and E. A. Widmer. 1977. Prevalence of Mesocestoides (Eucestoda: Mesocestoididea)
tetrathyridea in southern California reptiles with notes on the pathology in the Crotalidae. Jap.
J. Parasitol., 26:256—259.

McAllister, C. T. 1988. Mesocestoides sp. tetrathyridea (Cestoidea: Cyclophyllidea) in the iguanid
lizards, Cophosaurus texanus texanus and Sceloporus olivaceous, from Texas. J. Wild. Dis., 24:
160-163.

Read, C. P., and Y. U. Amrein. 1953. North American nematodes of the genus Pharyngodon Diesing
(Oxyuridae). J. Parasitol., 39:365—370.

Specian, R. D., and J. E. Ubelaker. 1974a. Parathelandros texanus n. sp. (Nematoda: Oxyuridae)
from lizards in West Texas. Trans. Amer. Microsc. Soc., 93:413-—415.

, and . 1974b. Two new species of Phryngodon Diesing, 1861 (Nematoda: Oxyuridae)
from lizards in West Texas. Proc. Helm. Soc. Wash., 41:46—51.

Stebbins, R. C. 1985. A field guide to western reptiles and amphibians. Houghton Mifflin Company,
Boston, xiv + 336 pp.

Telford, S. R., Jr. 1970. A comparative study of endoparasitism among some Southern California
lizard populations. Amer. Midl. Nat., 83:516—554.

Van Cleave, H. J. 1953. Acanthocephala of North American mammals. Illinois Biol. Monogr., 23:1—
179.

Webster, J. P- 1949. Fragmentary studies on the life history of the cestode Mesocestoides latus. J.
Parasitol., 35:83—90.

Accepted for publication 22 December 1997.

Bull. Southern California Acad. Sci.
97(2), 1998, pp. 86-88
© Southern California Academy of Sciences, 1998

Notes on the Late Prehistoric Extension of the Range for the
Muskrat (Ondatra zibethicus) along the Ancient Shoreline of Lake
Cahuilla, Coachella Valley, Riverside County, California

Robert M. Yohe II

Archaeological Survey of Idaho, Idaho State Historical Society
Boise, Idaho 83702

In 1990, a series of archaeological excavations was conducted by the Archae-
ological Research Unit (ARU), University of California, as part of environmental
assessments prepared in anticipation of several proposed development projects in
La Quinta, California. La Quinta, located in the northwestern Coachella Valley,
is 24 km (15 miles) southwest of Palm Springs in central Riverside County (Fig.
1). Three archaeological sites in La Quinta, CA-RIV-3682, CA-RIV-3144 and CA-
RIV-1182, yielded collections of subfossil vertebrate remains (interpreted as food
refuse) in addition to an array of cultural materials. These three archaeological
sites, as well as many others in the region, are believed to represent small fishing/
lacustrine resource gathering encampments located along the shore of prehistoric
Lake Cahuilla (also known as Lake LaConte; see Wilke 1978). This lake filled
the Salton Basin up to the Coachella Valley at various times until the latter part
of the sixteenth century (Weide 1976; Wilke 1978; Figure 1). At maximum fill,
Lake Cahuilla was a veritable inland sea with an estimated surface area of
1,256,550 acres (Weide 1976). The three prehistoric sites and associated subfossil
assemblages are thought to date to A.D. 1300 to 1500 based on several radiometric
analyses of fire-hearth samples (Arkush 1990; Yohe 1990), a period that represents
the last stand of Lake Cahuilla.

The analysis of the vertebrate faunal assemblages from the three archaeological
localities (conducted by the author) revealed a wide range of aquatic and terrestrial
taxa, the former confined to CA-RIV-3682. A summary of taxa identified at the
sites include several species of freshwater fishes (Xyrauchen texanus, Gila spp.,
Mugil cephalus, Ptychocheilus lucius, Elops affinis), reptiles (Gopherus agassizi,
Dipsosaurus dorsalis, Sceloperus sp., Crotalus sp.) some birds (Fulica americana,
cf. Anas acuta, Passeriformes), and numerous mammals, with the Audubon cot-
tontail (Sylvilagus audubonii) and woodrat (Neotoma sp.) dominating the mam-
malian assemblage (Yohe 1990). Of particular interest among the mammals at
these three sites are the remains of muskrat (Ondatra zibethicus). This is signif-
icant since the present range for this species is 130 km southeast of La Quinta
(Cockrum 1960; Grinnell et al. 1937; Ingles 1965; Willner et al. 1980). At all
three sites the Ondatra skeletal elements are rare, consisting of isolated mandib-
ular and maxillary molars (n = 8; CA-RIV-3682), assorted postcrania (1 ulna, 1
radius, 1 metapodial, 2 phalanges [CA-RIV-3144]); and a partial rostrum and
palate with complete molar series identified from CA-RIV-1182 (Arkush 1990).

In historic times, the range of the closest extant subspecies of Ondatra, the
Colorado muskrat (Ondatra zibethicus bernardi); has been both sides of the Col-
orado River and the New River to the south (Cockrum 1960; Grinnell et al. 1937;

RANGE OF MUSKRAT IN RIVERSIDE COUNTY 87

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(A.D. 900-1500) iF" y= B 7

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Fig. 1. Regional map of the Salton Basin and Coachella Valley, California with general locations
of archaeological sites discussed in text. Dark outline represents the approximate shoreline of prehis-
toric Lake Cahuilla, stippling represents the current range for Ondatra zibethicus.

Ingles 1965; Willner et al. 1980). It is also found along irrigation canals and
sloughs in the south end of the Imperial Valley. Prized for their pelts, the Colorado
muskrat was hunted and trapped extensively in the southern Imperial Valley in
the earlier part of the 20th century where it occurred in large numbers (Grinnell
et al. 1937). According to Grinnell et al. (1937), approximately 25,000 muskrats
were trapped in the Imperial Valley alone between 1919 and 1920.

The presence of late prehistoric muskrat remains in the northwestern Coachella
Valley places this genus more than 100 km north of its present accepted range.
Late Pleistocene/Early Holocene Ondatra fossils have been discovered in the east-
ern Salton Basin near East Mesa (Reynolds 1989), but no other paleontological
occurrences in southeastern California have been reported. Ondatra fossils are
rare in California. The only other known occurrence is a single femur from Cos-
teau Pit (Rancholabrean-age) in the Los Angeles Basin (Miller 1971). Archae-
ological occurrences of the muskrat from southern California also are rare; a few
Ondatra specimens have been recovered from San Joaquin Marsh in Newport
Bay at CA-Ora-119 and -193, where they were found in both cultural and natural
deposits ranging in age from ca. 6000 to 750 B.P. (Langenwalter 1986).

The course of the Colorado River, which has been naturally diverted on nu-
merous occasions Over the past several thousands of years to produce an inland
sea in the Salton Basin (Wilke 1978), has provided an environmental setting

88 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

attractive to various lacustrine vertebrates in the past. The archaeological sites
containing the Ondatra remains all appear to correspond temporally with the last
stand of Lake Cahuilla (A.D. 900—1500; Wilke 1978). Muskrat remains occurring
in the faunal assemblages of archaeological sites associated with ancient Lake
Cahuilla suggest that these animals once frequented the cattail marshes (which
were Clearly present based on paleobotanical studies of human coprolite contents
from numerous archaeological sites along the shoreline [see Wilke 1978; Farrell
1988]) on the northwest end of the lake, and were a source of food and possibly
pelts for the prehistoric occupants of the region more than 500 years ago.

Acknowledgments

I thank the following people for their comments on this note: Robert Reynolds,
Department of Earth Sciences, San Bernardino County Museum; Brooke S. Ar-
kush, Weber State University; Greg McDonald, Hagerman Fossil Beds National
Monument, Idaho; Bill Akersten, Department of Vertebrate Paleontology, Idaho
Natural History Museum, Idaho State University; Susanne J. Miller, Idaho Falls,
Idaho. I also thank Mark Q. Sutton for his assistance with the graphics.

Literature Cited

Arkush, B. S. 1990. Archaeological investigations at CA-RIV-1182, CA-RIV-3143, CA-RIV-3144,
CA-RIV-3868, and CA-RIV-3882, Tentative Tract 25429, La Quinta, Central Riverside County,
California. Report on file, Archaeological Research Unit, Department of Anthropology, Uni-
versity of California, Riverside.

Cockrum, E. L. 1960. The recent mammals of Arizona: their taxonomy and distribution. University
of Arizona Press, Tucson.

Farrell, N. 1988. Analysis of human coprolites from CA-RIV-1179 and CA-RIV-2827. Pp. 129-142
in Archaeological investigations at CA-RIV-1179, CA-RIV-2823, and CA-RIV-2827, La Quinta,
Riverside County, California (M. Q. Sutton and P. J. Wilke, eds). Coyote Press, Salinas, Cali-
fornia.

Grinnell, J., J. S. Dixon, and J. M. Linsdale. 1937. Fur-bearing mammals of California: their natural
history, systematic status, and relations to man. Contr. from the Mus. of Vert. Zool., University
of California Press, Berkeley.

Ingles, L. G. 1965. Mammals of the Pacific States: California, Oregon, and Washington. Stanford
University Press, Stanford.

Langenwalter, P. E. 1986. Indigenous muskrats, Ondatra zibethicus, in coastal Southern California.
Calif. Fish and Game 72(2): 121-122.

Miller, W. E. 1971. Pleistocene vertebrates of the Los Angeles Basin and vicinity (exclusive of Rancho
La Brea). Bull. of the Los Angeles Co. Mus. of Nat. Hist., Science, No. 10.

Reynolds, R. E. 1989. Paleontologic Monitoring and Salvage, Imperial Irrigation District Transmission
Line, Riverside and Imperial Counties, California: Final Report. Manuscript on file, Los Angeles
Co. Mus. of Nat. Hist.

Wilner, G. R., G. A. Feldhamer, E. E. Zucker, and J. A. Chapman. 1980. Ondatra zibethicus. Mam-
malian Species, No. 141, American Society of Mammalogists.

Weide, D. 1976 Regional environmental history of the Yuha Desert. Pp. 9-20 in Background to the
prehistory of the Yuha Desert Region (P. J. Wilke, ed.). Ballena Press Anthropological Papers
No. 5., Ramona, California.

Wilke, P. J. 1978. Late prehistoric human ecology at Lake Cahuilla, Coachella Valley, California.
Contributions of the University of California Archaeological Research Facility 38.

Yohe, Robert M. II, 1990. Archaeological investigations at five sites located at One Eleven La Quinta
Center in the city of La Quinta, Central Riverside County, California. Report on file, Archae-
ological Research Unit, Department of Anthropology, University of California, Riverside.

Accepted for publication 25 March 1998.

INSTRUCTIONS FOR AUTHORS

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McWilliams, K. L. 1970. Insect mimicry. Academic Press, vii + 326 pp.

Holmes, T. Jr., and S. Speak. 1971. Reproductive biology of Myotis lucifugus. J. Mamm., 54:452—458.

Brattstrom, B. H. 1969. The Condor in California. Pp. 369-382 in Vertebrates of California. (S. E. Payne, ed.),

Univ. California Press, xii + 635 pp.

PROCEDURE

CONTENTS

Range Extensions of Ten Species of Bats in California Denny G.
Constantine

Strategies of Predator Attacks on the Schooling Fish, Selar crumenophthal-
mus, 1n Academy Bay, Socorro Island, Islas Revillagigedo,
Mexico Bayard H. Brattstrom

Composition of the Helminth Community of a Montane Population of the
Coastal Whiptail, Cnemidophorus tigris multiscutatus (Sauria: Teiidae)
from Los Angeles County, California Stephen R. Goldberg, Charles
Re Bursey and ies Oo Wi 2g

Notes on the Late Prehistoric Extension of the Range for the Muskrat (On-
datra zibethicus) Along the Ancient Shoreline of Lake Cahuilla,
Coachella Valley, Riverside County, California Robert M. Yohe II -

COVER: Photograph of a school of jacks, Selar crumenophthalmus, in Academy
Bay, Soccoro island, Mexico. Photograph by Robert Pitman.

ISSN 0038-3872

PerdeERN CALIFORNIA ACADEMY OF . SCIENCES

BULLETIN

Volume 97 Number 3

BCAS-A97(3) 89-126 (1998) DECEMBER 1998

Southern California Academy of Sciences
Founded 6 November 1891, incorporated 17 May 1907

OFFICERS

Robert S. Grove, President
David Huckaby, Vice-President
Susan E. Yoder, Secretary
Robert Lavenberg, Treasurer
Daniel A. Guthrie, Editor
Hans Bozler, Past President
David Soltz, Past President

BOARD OF DIRECTORS

1997-1999 1997—2000 1998-2001
Ralph G. Appy Robert S. Grove Kathryn A. Dickson
Jonathan Baskin David Huckaby Donn Gorsline

J.D. Stewart Robert Lavenberg Robert E Phalen
Gloria Takahashi Kenneth E. Phillips Cheryl C. Swift

Susan E. Yoder

PHOLeSSiOnal IVECMIDEES oi eS a ak, 8) eek ahs a GPA AAU Cae tie 2 $35.00
SGident Miemibers: i Moo ee ee a ge ia Sr Ree Soh LS toate ie ee tk, ee Lh 20.00

Memberships in other categories are available on request.

Fellows: Elected by the Board of Directors for meritorious services.

The Bulletin is published three times each year by the Academy. Manuscripts for publication should
be sent to the appropriate editor as explained in “‘Instructions for Authors’’ on the inside back cover
of each number. All other communications should be addressed to the Southern California Academy
of Sciences in care of the Natural History Museum of Los Angeles County, Exposition Park, Los
Angeles, California 90007-4000.

Date of this issue 11 December 1998

SOUTHERN CALIFORNIA ACADEMY
OF SCIENCES

CALL FOR PAPERS
1999 ANNUAL MEETING
APRIL 30-MAY 1, 1999
CALIFORNIA STATE UNIVERSITY
DOMINGUEZ HILLS

f
“NcoRpoRATED 1%

Contributed Papers & Posters: Both professionals and students are welcome to submit abstracts for
a paper or poster in any area of science. Abstracts are required for all papers, as well as posters, and
must be submitted in the format described below. Maximum poster size is 32 by 40 inches.

Symposia: The following symposia will be held. If you wish to participate or to organize any addi-
tional symposia, please contact the organizer or the Academy Vice President, David Huckaby (562)
985-4869, dhuckaby @csulb.edu. Organizers should have a list of participants and a plan for reaching
the targeted audience.

Guns and Water: Management of Mesic Lands in Military Revervations in the Mojave Desert
Organizer: David Morafka (310) 243-3407

Water in the Desert: Past, Present, Future
Desert Studies: Consortium Symposium
Organizer: William Presch (714) 278-2428

Wetlands Restoration
Organizer: Ralph Appy (310) 732-3497

Artifical Reefs
Organizers: Robert Grove (626) 302-9735 and Ralph Appy (310) 732-3497

Status of Natural Resources
Organizer: contact David Huckaby (562) 985-4869

Contaminated Sediments in Southern California: Sticking your Head in the Mud
Organizer: Sue Yoder (213) 740-1965

Student Awards: Students who elect to participate are eligible for best paper or poster awards in a
variety of categories. A paper by any combination of student and professional co-authors will be
considered eligible provided that it represents work done principally by student(s). In the case of an
award to a co-authored paper, the monetary award and a one year student membership to the Academy
will be made to the first author only.

ite ee — oe
era |

1998 SCAS STUDENT AWARD WINNERS

(and honorable mentions*)

Janelle Johnson, Pacific Estuarine Research Laboratory, San Diego State University: Best Poster Award
for her poster entitled ‘“‘Fish Use of Southern California Salt Marshes” with Joy B. Zedler.

Rebecca Herrick, Department of Biology, California State University, Fullerton: Jules Crane Award
for the Best Paper for her paper entitled ‘“‘Do Biochemical Indices of Aerobic Capacity Correlate with
Swimming Speeds in Scombrid Fishes?”’ with K. A. Dickson.

Mason Posner, University of Southern California, Los Angeles County Museum of Natural History,
Fishes Section: Durham Memorial Award for Vertebrate Zoology for his paper entitled ‘‘Light Atten-
uating Molecules in the Lens of the Fish Eye.”

Ramon M. Valencia, Biology Department, California State University, Long Beach: ARCO Award for
Environmental Sciences for his paper entitled “An Assessment of the Toxicological Effects of Ingested
Copper and Tungsten-Tin-Bismuth (TTB) Bullets on the California Condor (Gymnogyps californi-
anus)’ with A. Silverman, A. Z. Mason, D. Clendenen, and R. Risebrough.

Steve Lonhart, Department of Biology, University of California Santa Cruz: Margaret Barber Award
for the Best Paper for his paper entitled “‘Comparison of Consumption Rates Among Benthic Inver-
tebrate Predators.”

Mauricio S. Ramos, Biological Sciences Department, California State Polytechnic University: Southern
California Academy of Sciences Award for the Best Paper for his paper entitled “‘Synthesis and
Cloning of Hammerhead Ribozyme Construct Targeted to Non-Variable Sequence of Mouse Leukemia
Virus Reverse Transciptase Gene”’ with B. K. Pal.

Maress Lacuesta, Biological Sciences Department, California State Polytechnic University: Honorable
Mention Award from the Southern California Academy of Sciences for the poster entitled ““Oxidative
and Glycolytic Metabolic Activities in Neurons and Microglial Cells are Altered in Rats Exposed to
High Doses of Ketamine”’ with W. J. Tulpinski, and G. H. Kageyama.

Junior Academy: Participants in organizations belonging to the Southern California Junior Academy
of Sciences will present their papers at sessions scheduled in a way to avoid conflict with Academy
meeting symposia and contributed paper sessions, thus permitting professional Academy members to
attend. High school students contributing papers through the Junior Academy should contact J. D.
Stewart (213) 763-3318.

Registration: All individuals attending the meeting including presenters at contributed paper, poster,
and symposia sessions are required to register for the meeting. However, all presenters will be offered
the early registration rate for Academy members or students, whichever applies.

INSTRUCTIONS FOR THE ABSTRACT/INFORMATION

Abstract Guidelines: Your abstract must not exceed 250 words of text, exclusive of title,
authors, and author affiliations. You must submit abstract in Microsoft Word format (any
version: DOS, Mac, or Windows) as an e-mail attachment to scas@dhvx20.csudh.edu by
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NOTE: use 12 point Ariel font if possible.

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ABSTRACT/INFORMATION FORMS MUST BE E-MAILED NO LATER THAN
MARCH 1, 1999.

SAMPLE ABSTRACT & INFORMATION

MICROBIAL ACTIVITY IN THE DIGESTIVE TRACT OF THE HALFMOON,
Medialuna californiensis. J. S. Kandel', J. R. Paterek* and M. H. Horn’, 'California
State Univ. Fullerton, CA 92634 and ?Agouron Institute, La Jolla, CA 92037.

We report the presence of a diverse microbial flora and of microbial fermentation
products in the hindgut region of the halfmoon, Medialuna californiensis, a seaweed-
eating fish from southern California coastal waters. Viable aerobic and anaerobic
bacteria were found in all sections of the gut, but were of highest concentration (10°—
10*/ml) in the hindgut. Microscopy revealed vibrios, spirilla, rod-shaped bacteria and
flagellated protozoa in the midgut and hindgut, but primarily vibrios and rods in the
stomach and foregut. Acetic, isobutyric and butyric acids, the volatile products of

microbial breakdown of carbohydrates, were found only in the hindgut, as was eth-
anol, a nonvolatile product. These results provide the first evidence for microbial
fermentation and its possible contribution to the energy supply in a north-temperate
herbivorous fish.

. Judy S. Kandel, Department of Biology, California State University, Fullerton, Fullerton, CA
92634, 714-773-2546. FAX 714-773-3426, jkandel @fullerton.edu. Nonmember

. J.R. Paterek, Agouron Institute, La Jolla, CA 92037. Nonmember

Michael H. Horn, Department of Biology, California State University, Fullerton, Fullerton, CA
92634, 714-773-3707. Member

. Professional

. Contributed paper

. Marine Biology, Microbiology, or Ichthyology

. Kodak 35mm slide carousel projector

Two New Stenosini Species in the Genus Araeoschizus LeConte
from Baja California, Mexico (Coleoptera: Tenebrionidae)

Charles S. Papp
7451 Albezzia Lane, Sacramento, California 95828

The first Araeoschizus species from the northern part of the Baja California
Peninsula was described by Blaisdell (1943) as antennatus collected at Punta
Prieta, by E. A. Michelbacher and E. S. Ross from the California Academy of
Sciences, in 1938. The most expansive collecting was done in the 1970s by E G.
Andrews, A. R. Hardy, T. D. Eichlin and M. Wasbauer from the California De-
partment of Food and Agriculture; their material supplied most of the specimens
for my revision of the genus (1981). Also, W. H. Clark, P. H. Blom, and others
from the Orma J. Smith Museum of Natural History, Albertson College, Caldwell,
Idaho and the University of Idaho, Moscow contributed generously to the further
study of this genus.

It was a puzzle for me to classify the material William H. Clark initially col-
lected in the broader San Agustin area. Subsequent collecting supplied more ma-
terial (over 700 specimens) from this area, where, according to I. L. Wiggins
(1980), four distinct plant communities meet: (1) the Californian Region, (2) the
Baja California Coniferous Forests, bordered to the west by (3) a Microphyllous
Desert habitat, and to the south by (4) the Sarcophyllous Desert Region (Fig. 1).

There are two recognized subspecies from this general area:

Araeoschizus antennatus clarki Papp (1989:335—337) is characterized as the
more slender form. Head narrower posteriorly (more so in many specimens).
Ocular lobe posterior to eye flat, not well outlined; ocular ridge shallow, with row
of dense, erect to semierect squamules. Prothorax similar to A. a. antennatus,
except the squamules on the longitudinal median ridge (creating the groove) and
those along the margin of the prothorax are goldish yellow, erect and long, longer
than those squamules of the ocular ridge. Elytral costae with dense row of some-
what shorter and erect squamules; rows of squamules in the elytral interspaces
are much smaller, sparsely spaced and posteriorly decumbent, like those parallel
with the tightly fused sutural line. Overall dark brown; prothorax slightly darker,
appendages slightly lighter in color; surface shiny. Known to occur in the Rancho
Santa Inez area (550 m elev.), found by W. H. Clark in foraging columns of the
ant Neivamyrmex nigrescens Cresson.

Araeoschizus antennatus blaisdelli Papp (1989:338) with much paler, less dense
and generally narrower squamules than A. a. clarki. The squamules at anterior
half of elytra slightly thinner and somewhat roundedly pointed; in posterior half
narrow and club shaped, resembling that of A. a. antennatus. Squamules on the
longitudinal ridges of the elytra are shorter, sparser; those in the interspaces shorter
and more sparsely spaced. Uniformly lighter brown; surface shiny. From the Ran-
cho Santa Inez area (550 m elev.); also found in Valle Montevideo La Laguna
Wash, 18 km W of Bahia de Los Angeles. W. H. Clark and P. E. Blom collectors.

On several collecting trips of William H. Clark and his collecting companions,

90 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Californian
Region

B.C. Coniferous
Forest

Microphyllous
Desert

Sarcophyllous
Desert

Sarcocaulescent
Desert

Magdalena
Region

Arid Tropical
Region

Sierra de la Giganta
Region

B.C. = Baja California
B.C.S.= Baja California Sur

Major Plant Communities in
Baja California, Mexico

After |. L. Wiggins:
Flora of Baja California
Stanford Univ. Press, 1980

(Redrawn by C.S. Papp, 1998)

Fig. 1. The eight plant communities of Baja California. The area encircled is where four com-
munities meet. (After I. L. Wiggins, 1980).

they were able to collect more specimens in a wider area of, as we now call it,
the Four Corners (Figs. | and 2).

Araeoschizus agustinus Papp, n. sp. (Fig. 3)

In some respects the species resembles squamulissimus Papp (1981) from Dia-
blo Dry Lake east of the Sierra de Juarez, some 50 miles W of the Colorado
River delta, but the latter species is far more squamulose, head longer than broad
with deeper and longer ocular groove; prothorax longer than broad and edges
heavily squamulose. Dark brown, shiny throughout.

Head.—Slightly (one-tenth) longer than broad, about evenly rounded. Ocular
groove shallow more so posterior to eye; ridge slightly elevated, with erect and
short squamules; ocular lobe similarly squamulose. Occipital triangular impression
shallow, occipital region roundly elevated. Surface minutely punctured and with
forwardly decumbent short pale squamules. Frontal edge fairly straight, slightly
serrated, with few longer, hair-like squamules. Eyes large, almost covering the
width of the ocular groove, with 20 facets dorsally and 5 ventrally. Antennae

NEW SPECIES OF ARAEOSCHIZUS FROM BAJA CALIFORNIA 9]

BAJA CALIFORNIA, MEXICO
From El Rosario to Punta Prieta

souyEL ROSARIO
Thm ae

30 40 MILES

50 60 KILOMETERS

iE of /” PUERTECITOS

mar Wess Guayaquil

E/N

amen
{

Pico Son San Agustin xo = bs
Pongo N@Rancho Sonora |
eee) Rogar > \

4
: A Pico Son Miguel
aoe — tifa”

are)

yy 2 Ss i,

/ Santa

Catarina £=¢,
| ae

“@ Santa Inez x
, is

erro Ugorle @ nme
(asa

/ ec 164
.,, Lodos Santos
3 aay

@) = The Catavina-Santa Inez area the
major collecting site of the Clark’s

Fig. 2. The major localities mentioned in the text.

robust; segments with row of forwardly decumbent narrow squamules on anterior
margins of all segments with thinner squamules on sides.

Prothorax.—About as long as broad (occasionally very slightly longer), ante-
rior margin broader with well defined anterior pronotal angle; moderately con-
stricted posteriorly with short pronotal angle. Longitudinal groove shallow and
relatively broad; ridges with semierect narrow squamules with posterior end of
ridges longer, rosette-like. Edge densely squamulose, about the size of squamules
on longitudinal ridge. Surface granulose, with sporadically spaced forwardly de-
cumbent squamules shorter than those on margin.

Elytra.—About one-third longer than head and prothorax combined. Sides in
middle two-thirds parallel; shoulders broadly, posterior end more narrowly round-
ed. Longitudinal ridges prominent, sharply elevated, on ridge with posteriorly
decumbent, curved, narrow squamules. Puncture lines very prominent; there are
no secondary rows of squamules. Sutural line shallow, with a row of somewhat
shorter and more sparsely spaced squamules than on longitudinal ridges.

®
92 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

hes

Fig. 3. Araeoschizus agustinus Papp, n. sp.

Underside

Head: Basal groove of sublabial plate deep; proboscis very shallow, frontal
margin straight. Gular impression very shallow (almost non-existent). Surface
coarsely punctate and very sparsely covered with forwardly decumbent short
squamules. Prothorax: Surface with larger punctures than head; prosternal ridge
evenly rounded; prosternal process narrow and more squamulose than rest of
prothorax. Hind body: Surface with large, deep punctures, each puncture with a
posteriorly decumbent short and thin squamula; these somewhat longer toward
posterior end of body. Legs: Medium pair smallest, posterior pair largest; sparsely
squamulose throughout; tarsi with somewhat longer, hair-like squamules.

Length: 4.1—4.5 mm.

Distribution

Holotype: San Agustin, elevation 580 m, in Ethylene Glycol Pitfall Trap
(EGPT), VI. 16. 1991 to V. 27. 1992, William H. Clark, Paul E. Blom and Ellen
M. Clark collectors. In the Orma J. Smith Museum.

Paratypes: 12 specimens from the same location (in EGPT).

Additional specimens (all in EGPT): 3 from the same location, VI. 20. 1990—

NEW SPECIES OF ARAEOSCHIZUS FROM BAJA CALIFORNIA oS

III. 10. 1991 by W. H. and Ellen M. Clark collectors.—14 from 1 mi N of Santa
Catarina (Ranch), XII. 9. 1991—VIII. 3. 1992 by W. H. Clark and P. E. Blom
collectors.—8 from 1.5 km SW from Guayaquil, elev. 600 m, VI. 16. 1991—V.
27. 1992 by W. H. & E. Clark, P E. Blom and David M. Ward collectors.—10
from 10 km SE Rancho Sonora, elev. 600 m, III. 12. 1991—VII. 16. 1991 by W.
H., M. H., C. J. & K. D. Clark and Jane C. Luther collectors.—2 from 9 km NW
Santa Inez, VII. 17. 1991—V. 26. 1992 by W. H. and E. M. Clark collectors.—1
from 2 km E Mission San Fernando, elev. 480 m III. 12. 1991—VII. 3. 1991.—7
from 11 km ENE El Rosario, elev. 140 m VI. 22. 1991 -III. 9. 1992.—1 from
Valle Montevideo Wash, 18 km W Bahia de Los Angeles, elev. 380 m, III. 19.
1991-VIII. 19. 1991.—1 from Rancho La Ramona, elev. 500 m, III. 21. 1991—
VII. 3. 1991.—4 from 2 km E Mission San Fernando, elev. 480 m, VII. 3. 1991—
V. 20. 1992 by W. H. Clark collector.

Araeoschizus blomi Papp, n. sp. (Fig. 4)

Resembles antennatus Blaisdell (1943), however blomi can easily be differ-
entiated by the robust antennae, the narrow posterior portion of head, the more
prominent longitudinal groove of prothorax and the unique arrangement of squa-
mules. Secondary row of squamules hardly detectable. Brown to blackish brown,
shiny; also smaller.

Head.—A\lmost twice as long as prothorax; occipital portion narrowly rounded
with prominent, yet small, occipital impression. Ocular lobes only slightly ele-
vated, rounded, inner ocular ridge angularly placed (parallel to margin of head in
antennatus), short, slightly elevated with prominent row of decumbent squamules.
Ocular groove short, abruptly flattened posteriorly. Vertex round, evenly elevated,
a slight horizontal impression between ocular lobes separates it from the nearly
flat frons. Surface finely punctured, with forwardly decumbent squamules. Sides
with erect longer squamules, more sparsely spaced on anterior margin. Frontal
margin almost straight, with several semierect spine-like squamules. Eyes with
14-16 facets dorsally, with 5—6 facets ventrally. Antennae more robust; joints are
Squamulose, more densely so on anterior margin of each segment.

Prothorax.—Anterior margin slightly curved inwardly, angles more narrowly
rounded than that of antennatus, posterior third constricted. Longitudinal groove
evenly deep, one third as wide as length of posterior margin of prothorax; finely
punctured. Ridges with long, erect squamules (see top insert of Fig. 4), anterior
and posterior end slightly decumbent, as long as squamules on margin of protho-
rax, which are on sides horizontally, on anterior and posterior margin vertically
erect, on the latter somewhat shorter, dense, more numerous. Surface finely punc-
tured, with very few forwardly decumbent short squamules.

Elytra.—Slightly longer than head and prothorax combined. Shoulders narrow-
ly rounded, sides in mid-third almost parallel. Primary cordae prominent, on fron-
tal fourth longer, erect, other places with shorter and posteriorly decumbent, slight-
ly club-shaped squamules. Puncture lines are prominent, punctures deep, closely
Spaced; secondary row of squamules between them hardly detectable, consists of
Short, thin, sporadically spaced, posteriorly decumbent squamules. Sutural line
Slightly elevated and with very short, thin, posteriorly decumbent squamules.

94 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Sint ad -F

a 98

7) as

* NogS a
YY ' ax S yy
v3. EAD S iS
7a WAP Pe § N
BY "4 q ( 4 § yy;
ie C73 yt SS Am)
ye aays IA
Abe ot RAPES alae
AIK AY A\ te
pie) d AS

Fig. 4. Araeoschizus blomi Papp, n. sp.

Underside

Head: Densely punctured; with few forwardly decumbent squamules. Basal
groove of sublabial plate deep, posteriorly extended into a rounded-triangularly
shaped impression about half way to the very deep gular impression. Margin of
sublabial plate straight; wide, proboscis long, sharply pointed, at base deeply
carinate. Prothorax: Prosternal ridge highly elevated, with few, very short, erect
squamules on ridge. Coarsely punctured. Prosternal process broad and with round-
ed posterior margin; squamulose. Hind body: With large, closely fit punctures,
each puncture with narrow, posteriorly decumbent thin squamules longer than
diameter of punctures. Legs: Middle pair smallest, hind pair largest; covered with
relatively long narrow squamules, these thinner and longer toward tip of tibia;
longer and thinner on tarsi.

Length: 3.8—4.1 mm.

Distribution

Holotype: 9 mi N of Rancho Santa Inez, elevation 550 m, in EGPT, III. 18.
1991—VII. 17. 1991, by W. H., Mary H., Cynthia J. & Caren D. Clark and James
C. Luther collectors. In the Orma J. Smith Museum of Natural History.

NEW SPECIES OF ARAEOSCHIZUS FROM BAJA CALIFORNIA 95

Paratypes: 12 specimens, same location, same collectors; in the same Museum.

Additional specimens (all in EGPT): 45 from San Agustin, elevation 580 m,
III. 10. 1991—VII. 16. 1991, same collectors; additional 21 specimens from the
same location XII. 21. 1988—VIII. 29. 1989 by W. H. Clark collector.—2 from 2
km SE Rancho Sonora, VII. 16. 1991—V. 27. 1992, W. H. & E. M. Clark and P.
E. Blom collectors.—3 from 5 km SW Guayaquil, 600 m elevation, III. 23. 1991—
VIII. 3. 1991 and VII. 3. 1991—V. 27. 1992 by the same collectors.—3 from Santa
Inez, III. 13. 1991—VII. 17. 1991 by W. H. and Mary H. Clark collectors; 11
specimens VII. 4. 1991-I. 4-5, 1992 by W. H. Clark and P. E. Blom collectors.

It will be interesting to see what specimens the Clarks come up with south
from Santa Inez. No doubt, antennatus was reported in the above mentioned
general area (Papp, 1981:324) 13 mi E from El Rosario, collected by G. E. & E.
S. Ross and V. L. Vesterby in 1938 and later by W. H. Clark in 1978 to recently.
It would be interesting to find out the distribution of this species further to the
south and behind the type locality, Punta Prieta. I believe antennatus is the dom-
inant species in the center two-thirds of Baja California.

In the collection of the California Academy of Sciences there is a specimen
from Baja California Sur with spines on all femora and with secondary rows of
squamules on elytra. The specimen was collected by S. C. Williams in an isolated
area at San Migual de Comundu at 1500 ft. elevation on April 21, 1969. This
area should be intensively collected. This unique specimen belongs to Group I in
the key (Papp, 1981:295), the first ever collected in the southern portion of the
Baja California Peninsula.

Literature Cited

Blaisdell, EF E. 1943. Contribution Toward the Knowledge of the Insect Fauna of Lower California.
No. 7: Coleoptera, Tenebrionidae. Proc. Calif. Acad. Sci. 24(7):171—188, pls. 10 and 11.

Papp, C. S. 1981. Revision of the Genus Araeoschizus LeConte (Coleoptera: Tenebrionidae). Ent. Arb.
Mus. Frey, 29:273—420, 68 figs.

. 1989. Notes on the Stenosini genus Araeoschizus LeConte from Baja California, Mexico
(Coleoptera: Tenebrionidae). Entomography, 6:335—340, 3 figs.

Wiggins, I. L. 1980. Flora of Baja California. Stanford University Press, 1025 pp., 970 figs. (see pp.
21-26).

Accepted for publication 7 May 1998.

Distribution and ‘Taxonomic Remarks for Five Crab Species of the
Family Grapsidae (Crustacea: Sesarminae and Varuninae) of the
Mexican Pacific

Ernesto Campos and Alma Rosa de Campos

Facultad de Ciencias, Universidad Aut6noma de Baja California,
Apartado Postal 2300, Ensenada, B.C., 22800 México

Abstract.—The present report updates the distribution of Armases magdalenense
(Rathbun, 1918), Hemigrapsus oregonensis (Dana 1851) and Goetice americanus
Rathbun 1923 along the Baja California coast. Previous records of Tetragrapsus
jJouyi (Rathbun 1893) to the rocky intertidal of Punta Pelicano, near Puerto Pef-
asco, Sonora, are rejected. These were based on misidentifications of specimens
of G. americanus. Tetragrapsus jouyi is known from salt marsh areas of Guaymas,
Sonora, and Bahia de Los Angeles, Baja California (new locality). The presence
of Hemigrapsus nudus in the Gulf of California is not confirmed. It undoubtedly
occurs on the west coast of the Baja California Peninsula northward to Alaska,
U.S.A. An identification key to the Varuninae of the East Pacific is provided.

Resuimen.—E\ presente trabajo actualiza la distribuci6n de Armases magdalenense
(Rathbun, 1918), Hemigrapsus oregonensis (Dana 1851) and Goetice americanus
Rathbun 1923. Se rechazan los registros previos de Tetragrapsus jouyi (Rathbun
1893) para el intermareal rocoso de Punta Pelicano, cerca de Puerto Penasco,
Sonora. Estos fueron identificaciones incorrectas de especimenes pertenecientes a
G. americanus. Tetragrapsus jouyi se conoce para saladares de Guaymas, Sonora
y Bahia de Los Angeles, Baja California (nueva localidad). No se confirma la
presencia de Hemigrapsus nudus en el Golfo de California. Esta especie ocurre,
con certeza, en la costa occidental de la peninsula de Baja California y hacia norte
hasta Alaska, E.U.A. Se provee una clave para identificar las especies de la sub-
familia Varuninae del Pacifico Oriental.

The study of specimens collected in the Gulf of California and of others bor-
rowed from several institutions allows us to correct and update the distribution
of 5 species of grapsid crabs (1 Sesarminae and 4 Varuninae) of the East Pacific.
Information presented herein update those reported by Hendrickx (1995). For each
species listed, some taxonomic and ecological remarks based on the new material
are presented. In addition, a comparative morphological analysis allows us to
provide a key for the members of the subfamily Varuninae of the East Pacific.

Material and Methods

This study is largely based on material collected by the authors along the Baja
California Peninsula and Sonora coast, north to parallel 31°N. Additional material
came from the Invertebrate Collection (Crustacea) of the Scripps Institution of
Oceanography, University of California, La Jolla, California (SIO) and the In-
vertebrate Collection of the Peabody Museum of Natural History, Yale University,

GRAPSIDAE OF THE MEXICAN PACIFIC o7

ah en ), wreagheat y

“et

Fig. 1. Armases magdalenense (Rathbun 1918); A, male holotype dorsal view; B—C dactyli of the
fourth walking leg (A—C from Abele 1992).

New Haven, Connecticut (YPM). The Baja California records of Hemigrapsus
oregonensis provided by the late John S. Garth, are based on material of the Allan
Hancock Foundation, from collections made primarily by the “‘Velero IV”’,
“Searcher”? and *““The Kenyon-Williams”’ expeditions. This material is in the Nat-
ural History Museum of Los Angeles County (LACM). Voucher specimens are
deposited in the Laboratorio de Invertebrados, Facultad de Ciencias, Universidad
Aut6noma de Baja California (UABC). Other abbreviations used are: Gulf of
California (GC); Baja California (BC); Baja California Sur (BCS); Sonora (SON);
Departamento de Investigaci6n Cientifica y Tecnologica, Universidad de Sonora
(DICTUS).

Taxonomic Account
Family Grapsidae MacLeay 1838
Subfamily Sesarminae Dana 1851
Armases magdalenense (Rathbun 1918)
Fig. 1A—C

Previously known distribution.—Bahia Magdalena, west coast of BCS and from
Bahia Altata, Altata, Sinaloa (GC), to Agua Brava, Nayarit (Abele 1992; Hen-
drickx 1993, 1995; Villalobos-Hiriart et al. 1989).

Material examined.—20+ males and ovigerous females, Estuary of Mulegé
River, Mulegé, BCS (GC), 30 Jul 1996.

Remarks.—Four species of the genus Armases Abele 1992 have been recorded
along the East Pacific: A. angustum (Smith 1870) (Mexico to Ecuador); A. occi-

98 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

dentale (Smith 1870) (El Salvador to Ecuador); A. gorei (Abele 1981) (Peru) and
A. magdalenense (Rathbun 1918) (Mexico), (see Abele 1992). Armases magda-
lenense can be separated from other species for its carapace (Fig. 1A), distinctly
wider than long (cl/cb = 0.83), the extensor margin of the dactyl of the last
walking leg is also armed with black spines (Fig. 1B—C) and the palm of the
chela is smooth (Abele 1992).

The present record extends the northern distribution limit of A. magdalenense
in the GC approximately 300 km. It is a common but inconspicuous crab along
banks of estuary of the Mulegé River and its habitat agrees with that reported by
Hendrickx and Salgado-Barragan (1992): under dead plants on sandy substrate,
in the shade of mangrove trees above the water line. Two species of fiddler crabs,
Uca latimanus (Rathbun 1893) and U. crenulata crenulata (Lockington 1877),
and the grapsoid crab Geograpsus lividus (H. Milne-Edwards 1837) were col-
lected in the same habitat.

Subfamily Varuninae H. Milne-Edwards, 1853
Goetice americanus Rathbun 1923
Fig. 2A—B

Previously known distribution.—GC, Bahia San Luis Gonzaga, BC, and Guay-
mas, SON; west coast of the BC Peninsula at Bahia Tortugas (=San Bartolomé),
BCS (Rathbun 1923).

Material examined.—100+ males and females, San Felipe and vicinity, BC,
Puerto Pefiasco, SON, Bahia de Los Angeles, BC, and Bahia Concepcion, BCS,
1985-1995.

Remarks.—Goetice americanus is the most abundant brachyuran crab of the
highest rocky intertidal of the GC. It is a common species from Bahia de Los
Angeles, BC north to San Felipe, BC and Puerto Pefiasco, SON, but is rare at
Bahia Concepcion and southward along the BC peninsula coast. Hendrickx (1994)
reported G. americanus to Guaymas. However, his collecting efforts along the
tropical Pacific (see Hendrickx 1995) and that of ours on the west coast of the
BC peninsula (1985-1997) had failed to produce specimens of this species. Our
findings suggest that Rathbun’s (1923) record of G. americanus to Bahia San
Bartolomé (=Bahia Tortugas) on the west coast of the BC Peninsula is extra-
limital.

Goetice americanus can be easily recognized by its coloration. The carapace
has a marble color with a great deal of variation of white, red and gray. Ovigerous
females have been collected in January, April and November.

Additional remarks on this species are under Hemigrapsus nudus (Dana 1851)
and Tetragrapsus jouyi (Rathbun 1893).

Hemigrapsus oregonensis (Dana 1851)
Fig. 3A

Known distribution.—From Resurrection Bay, Alaska to Bahia San Juanico,
BCS (Campos and Campos 1989); San Felipe and Bahia de Los Angeles, BC
(Luke 1977).

Material examined.—14 juveniles, Estero Uno, north of Campo Don Abel, San
Felipe, BC, 17 Mar 1995 (UABC); 20 males, 20 females, Laguna Percebt, San
Felipe, BC, several dates (UABC); one ovigerous female, Guerrero Negro, BCS,

GRAPSIDAE OF THE MEXICAN PACIFIC 99

Fig. 2. A-—B, Goetice americanus Rathbun 1923; C, Hemigrapsus nudus (Dana 1951). A, C, frontal
view; B, dorsal face of the fourth walking leg.

21 Mar 1956 (LACM); 12 males, 12 females, Bahia Todos Santos, BC, 16 Apr
1980; 22 Nov 1996 (UABC); one male, two females, Bahia Tortugas, BCS, Jan-
Apr 1987 (UABC); number and sex not available, Bahia San Juanico, BCS, 8
February 1955 (LACM).

Remarks.—See remarks under H. nudus.

Hemigrapsus nudus (Dana 1851)
Fig: 2€

Known distribution.—From Yakobi Island, Alaska to Bahia Tortugas, BCS.
Mexico (Garth and Abbott 1980); presumably Bahia de Los Angeles (Luke
1977).

Material examined.—1 male, 1 female, Bahia Todos Santos, Ensenada, BC, no
date available.

100 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Fig. 3. A, Hemigrapsus oregonensis (Dana 1851); B—C Tetragrapsus jouyi (Rathbun 1893). A, C,
frontal view; B, dorsal face of the fourth walking leg.

Remarks.—Rathbun (1923), Brusca (1980) and Garth and Abbott (1980) were
hesitant about records of H. oregonensis and H. nudus in the Gulf of California.
Hendrickx (1995), based on Luke’s (1977) account, recorded these species to San
Felipe, BC and Bahia de Los Angeles, BC respectively. The study of the material
on which Luke (1977) based the records of H. oregonensis (SIO: C373, C375,
C379, C1334) permits us to confirm the presence of this species in the upper Gulf
of California. However, part of this material belongs in Goetice americanus. The
presence of H. nudus is not confirmed by the present study. The only lot of
specimens (SIO—C366) that supports Luke’s report was not found in the SIO
Crustacean Collection (C366). On the northeast Pacific coast Hemigrapsus nudus
lives under rocks in the middle and higher intertidal. Hemigrapsus oregonensis,
a burrower species, inhabits open mud flats, under rocks in muddy habitats, or in
mats of Enteromorpha and beds of Zostera, high to low intertidal (see Garth and
Abbott 1980; Bonfil et al. 1992).

GRAPSIDAE OF THE MEXICAN PACIFIC 101

Tetragrapsus jouyi (Rathbun, 1893)
Fig. 3B—C

Known distribution.—GC, Guaymas, SON (Rathbun, 1918); ‘‘quiet waters from
Puerto Pefiasco to Mazatlan, Espititu Santo Island and San Francisco and La Paz,”’
Mexico (Vogel 1966; Brusca 1980).

Material examined.—40+ specimens, Bahia de Los Angeles, BC, Mar 1987
and Jul 1996.

Remarks.—Tetragrapsus jouyi was originally recorded in Guaymas, SON
(Rathbun 1918). Later, Vogel (1966) reported this species in Punta Pelicano, a
locality close to Puerto Penasco, SON. Brusca (1980) pointed out that it is a
common and abundant species throughout the Gulf of California, living under
rocks. We have examined the 25 males and 13 females (YPM 5698) on which
Vogel (1966) based her report and they belong in Goetice americanus. The spec-
imens reported by Brusca (1980) were not found in the Puerto Pefiasco Laboratory
of the DICTUS or elsewhere. Their identity remains uncertain. Brusca (in litt.)
informed us that many of his records, including that of T. jowyi, were based solely
on field identifications, which further complicates this inquiry. We believe that
the grapsoid crab Brusca (1980) recorded as common and abundant under rocks
along the Gulf of California is either G. americanus, H. oregonensis or both. Our
conclusion is supported by the fact that 7. jouyi occurs intertidally in salt marsh
habitat. In Bahia de Los Angeles, it burrows among the pickle weeds (Salicornia
pacifica) and grasses (Distichiis spicata). Tetragrapsus jouyi never occurs under
rocks as do G. americanus and H. oregonensis.

Varuninae of the Mexican Pacific.—Six species of Varuninae occur along the East
Pacific coast. Except for Glyptograpsus impressus Smith 1870 (Acapulco, Mexico
to Panama) and Euchirograpsus pacificus Tiirkay 1975 (Galapagos) (see Tiirkay
1975; Hendrickx 1995), the remaining species G. americanus, H. nudus, H. orego-
nensis and T. jouyi occur intertidally in temperate and sub-tropical waters of the
Mexican Pacific. They inhabit the SON and BC coast, in the upper GC and the west
coast of the BC Peninsula along the Californian Province. The Varuninae of the
Mexican Pacific are morphologically similar, particularly in the general shape of the
carapace, third maxilliped, and chelipeds. This similarity among these species has
resulted in misidentifications. A detailed morphological comparison of these species
allowed us to recognize several features of the carapace, abdomen and walking legs
that permit easy recognition of each species. These features have been summarized
in the key below. Regarding habitat, H. oregonensis and T. jouyi prefer salt marsh
areas. However, the former may also live under rocks in muddy habitats. Hemigrap-
sus nudus and G. americanus inhabit rocky intertidal areas.

Key to the Grapsidae-Varuninae of the East Pacific

1. First segment of male abdomen covering entire sternum between legs of

TAS DAMME re PA a RE NER ae os oo ss ent one Pian em Sale oe Biel Baw eee 3)
1’. First segment of male abdomen not entirely covering the sternum heres

Fe SemO lel Aste caliypes yao aN. cu acer ao Biel ae eae Sub RS ae wee ee 2
2. Walking legs 1—4 stout, bare or with scatter, short tufts of hair setae (Fig.

OED ee verre Pete REIN ooo cae ds Ae Oe Bole eh wie MlAew team tied 3

Zee Walking legs 1-4 slender and hairy (Fig. 3B). .........0.0.20205..7.5-. 4

102 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Fig. 4. A, Euchirograpsus pacificus Tiirkay 1975, male holotype; B, Glyptograpsus impressus
Smith 1870, male dorsal view (A from Tiirkay 1975; B, Rathbun 1918 respectively).

3. Antero-lateral margins of carapace straight and parallel, front deeply
emarcinate, (Fil. DA) Wi Ale he ee, Goetice americanus Rathbun 1923
3’. Antero-lateral margins arcuate, front gently emarginate (Fig. 2C) .....
MA EIR La Pet See a: a Hemigrapsus nudus (Dana 1851)
4. Front deeply emarginate, with two prominent dorsal lobes (Fig. 3A) ..
S Loaweeaiah, See saeets Wire SEES SE AEG. RH Hemigrapsus oregonensis (Dana 1851)
4’. Front gently emarginate, without prominent dorsal lobes (Fig. 3C) ....
ste Gees AP AEA ES Tetragrapsus jouyi (Rathbun 1893)
5. Carapace squarish, lateral margins straight (Fig. 4A) ................
iteyen etek: th Mie ch aes, eee ee Euchirograpsus pacificus Tiirkay 1975
5’. Carapace subrotund, lateral margins arcuate (Fig. 4B) ...............
ih deat cox Dede oe ene Glyptograpsus impressus Smith, 1870

GRAPSIDAE OF THE MEXICAN PACIFIC 103

Acknowledgments

Our great appreciation is due to Eric Lazo-Wasem, Manager Collection, Pea-
body Museum of Natural History, Yale University, for making available part of
the reported material; to Richard C. Brusca, Michel Hendrickx, Raymond B. Man-
ning and Michael Tiirkay for supplying pertinent literature and sharing important
information; to José Delgadillo for the identification of the salt marsh plants; to
Eduardo, Carmina, Lalito and Paulina Aguirre y Gonzalez, and Tony Resendis
for their invaluable support during an academic sojourn at Puerto Pefiasco Lab-
oratory, DICTUS and The Archleon campus, Bahia de Los Angeles respectively.
This work was supported by the agreement CONACyT-UABC 3587-N9311.

Literature Cited

Abele, L. G. 1992. A review of the grapsid crab genus Sesarma (Crustacea: Decapoda: Grapsidae) in
America, with the description of a new genus. Smith. Contr. Zool. 527:1—60.

Bonfil, R., A. Carvacho, and E. Campos. 1992. Los cangrejos de la Bahia de Todos Santos, Baja
California. Parte II. Grapsidae, Pinnotheridae y Ocypodidae (Crustacea: Decapoda: Brachyura).
Ciencias Marinas 18(3):37—56.

Brusca, R. C. 1980. Common intertidal invertebrates of the Gulf of California. University of Arizona
Press, Tucson, 513 pp.

Campos, E. and A. R. de Campos. 1989. Range extension of Decapod Crustaceans from Bahia Tor-
tugas and vicinity, Baja California Sur, Mexico. Calif. Fish and Game 75:174-177.

Garth, J. S., and D. T. Abbott. 1980. Brachyura. The true crabs, chapter 25. Pp. 594-630 in Intertidal
Invertebrates of California. (R. H. Morris, D. P. Abbott, and E. C. Haderlie, eds.), Stanford
University Press, Stanford, California.

Hendrickx, M. E. 1993. Crustaceos decapodos del Pacifico mexicano. Pp. 271-318 in Biodiversidad
Marina y costera de México. S. I. Salazar-Vallejo and N. E. Gonzalez (eds.). CONABIO-
CIQRO, México.

. 1994. Catalogo de crustaceos estomat6podos y decapodos. Coleccién de referencia, Estacion

Mazatlan. Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Aut6noma de

México-Comisi6n Nacional para el Conocimiento y uso de la Biodiversidad, 134 pp.

. 1995. Checklist of brachyuran crabs (Crustacea: Decapoda) from the eastern tropical Pacific.

Bull. Inst. Roy. Sci. Nat. Belgique (Biologie) 65:125—150.

, and J. Salgado-Barragan. 1992. New records of two species of brachyuran crabs (Crustacea:
Decapoda: Brachyura) associated with tropical coastal lagoons on the Pacific coast of Mexico.
Rev. Biol. Trop. 40(1):149—150.

Luke, S. R. 1977. Catalog of the benthic invertebrate collection, I. Decapod Crustacea and Stomato-
poda. University of California, Scripps Institution of Oceanography. Reference Series 77—9: 72 pp.

Rathbun, M. J. 1918. The grapsoid crabs of America. Bull. U.S. Nat. Mus. 97:1—461.

. 1923. Scientific results of the expedition to the Gulf of California by the U.S. Fisheries
Steamer ‘“‘Albatross”’ in 1911. XIII. The brachyuran crabs collected by the U.S. Fisheries Steam-
er “Albatross” in 1911, chiefly on the west coast of Mexico. Bull. Amer. Mus. Nat. Hist. 48:
619-637.

Tiirkay, M. 1975. Zur Kenntnis der Gattung Euchirograpsus mit Bemerkungen zu Brachygrapsus und
Litocheria (Crustacea: Decapoda). Senckenbergiana Biol. 56(1/3):103—132.

Villalobos-Hiriart J. L., J. C. Nates-Rodriguez, A. Cantu-Diaz-Barriga, M. D. Valle-Martinez, P. Flores-
Hernandez, E. Lira-Fernandez, and P. Schmidtsdorf-Valencia. 1989. Listados Faunjisticos de
México. I. Crustaéceos estomatépodos y decapodos intermareales de las Islas del Golfo de
California, México. Instituto de Biologia, Universidad Nacional Aut6noma de México, 114 pp.

Vogel, B. R. 1966. A report on a collection of crabs from the Gulf of California. Southwest. Nat.
11(1):139-140.

Accepted for publication 29 December 1997.

A Dietary Analysis of Hippoglossina stomata Eigenmann and
Eigenmann, 1980 (Pisces: Bothidae) along the Western Coast of
Baja California, Mexico

Ricardo R. Murillo,
A. A. Ortega-Salas,
and Marco A. Martinez-Mufioz

Instituto de Ciencias del Mar y Limnologia, UNAM, México 04510, D.F.

Abstract.—A benthic trawl survey was conducted at depths of 38 to 218 m in
September of 1990 along the western coast of Baja California on board the R/V
E] Puma. A dietary analysis of 67 Hippoglossina stomata stomachs was made in
order to contribute to the knowledge of the diet of this species. Crustaceans,
principally Pleuroncodes planipes (44.8%), and stomatopods, Hemisquilla ensi-
gera californiensis (41.3%), were the most important prey items. Small crusta-
ceans such as Malacostracea, Penaeidae, Decapoda not identified represent 5%.
Fish and others were also consumed (8.4%).

The geographical and bathymetric range of the bigmouth sole, Hippoglossina
stomata spans from Monterey Bay, California, USA to Cabo San Lucas and into
the Gulf of California, México (Roedel 1953; Berdegué 1956; Eschmeyer et al.
1983) at depths from 30 to 240 m (Martinez and Ramirez 1992).

The bigmouth sole is a relatively abundant flatfish inhabiting soft sediments on
the continental shelf of southern Baja California, Mexico. It could be of com-
mercial importance (300 mm) due to the excellent quality of its meat (Berdegué
1956). Ecologically it is important since it preys on mysids, gammarideans and
amphipods (Allen 1982), as well as the red crab, Pleuroncodes planipes (Ramirez-
Murillo 1995). In turn, this species serves as food for the California sea lion,
Zalophus californianus (Aurioles et al. 1984).

The taxonomy of the genus Hippoglossina was studied by De Buen (1961).
Leonard (1971) studied the larvae of Hippoglossina oblonga. Yany et al. (1977)
surveyed the food intake of Hippoglossina macrops in Valparaiso. Goldberg
(1982) studied the seasonal spawning cycles of Hippoglossina stomata in Mag-
dalena Bay, Mexico and Ramirez-Murillo (1995) examined the age and growth
of H. stomata in Baja California. The purpose of the present study was to provide
a preliminary knowledge of the food intake of H. stomata, off the western coast
of Baja California, Mexico.

Materials and Methods

During September of 1990, a demersal trawl survey was conducted along the
western continental shelf off Baja California from the northern portion of Bahia
Vizcaino to the southern part of Magdalena Bay, between 24° and 28°30’N latitude
and 111°30’ and 114°30’W longitude (Fig. 1).

The samples were collected by the R/V El Puma, at depths between 38 and
218 m using a shrimp otter trawl] net, with a mouth opening of 21 m and 3 cm

104

DIETARY ANAYLSIS OF HIPPOGLOSSINA OFF BAJA 105

Hippoglossina stomata

114°

Fig. 1. Sampling stations from the EP9009 cruise, September, 1990.

mesh size. The catch was discharged on the deck and its contents counted and
identified.

The H. stomata specimens were separated into plastic bags and fixed in 10%
formalin for later transport to the laboratory.

The dietary analysis involved the following:

1. Stomachs were extracted, fixed and maintained in 10% formalin.

2. Food items were identified and counted. Those too difficult to identify were
considered unknown remains and were not considered in the analysis.

3. State of digestion of prey was noted according to the method of Banner (1948a,
b) and Brusca (1980).

4. Numeric, volumetric, frequency of occurrence and relative importance (IRI)
of each taxon to the diet of these fish were determined using the methods of
Pinkas et al. (1971): IRI = (7 N + % V)(FO)

106 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

where:

N: numeric percentage; V: volumetric percentage; FO: frequency of occur-
rence.

Results

Of the 30 trawling operations carried out off the west coast of Baja California,
H. stomata was present in 25 hauls (83% FO), rendering a total of 450 specimens
with the greatest abundance in the area between the 24th and 27th N parallel.
The minimum standard length of the fish sampled was 70 mm and the maximum
258 mm with an average of 171 mm. The main species associated with H. stomata
were Prionotus stephanophrys, Citharichthys xanthostigma, C. fragilis, Merluc-
clus augustimanus, and Synodus lucioceps.

Among the total of 67 H. stomata stomachs sampled, 11 were empty (16.4%).
The remaining 56 stomachs belonged to individuals of standard length between
87 and 125 mm, with an average of 106.8 mm.

Analysis of the diet indicates that H. stomata feeds on a benthopelagic fauna
as well as an epibenthic one. The stomachs analyzed are from relatively small
and immature individuals. Crustaceans were the most important prey groups over-
all in the diet of this species, followed by osteichthyes and others (Table 1).

Among the 105 prey items observed, 7 families, 6 genera and 2 species could
be identified by means of the analysis. The most abundant food item was the red
crab, Pleuroncodes planipes with 45.4% V, 29.8% FO and 44.8% IRI, while in
some stations the stomatopod, Hemisquilla ensigera californiensis was more
abundant, with 29.8% V, 30.3% FO and 41.34% IRI. It does suggest some trends,
when the distribution of Pleuroncodes is juxtaposed with the shift in dominance
of the diet from Pleuroncodes to stomatopods.

Preference for eating the red crab, Pleuroncodes planipes (44.8% IRI) occurs
when this species is most abundant. When P. planipes is absent, it is replaced in
the diet by other species, like Hemisquilla ensigera californiensis (41.34% IRI),
which live in shallower waters, and by other species, including fish, which total
13% IRI. Thus, diet diversifies based on food availability. As indicated by its
large mouth and eyes and by its tooth type, Hippoglossina stomata feeds by
settling to the bottom and waylaying its food.

Discussion

Studies of ecological communities are based on the organisms and their envi-
ronmental relationship, which could be observed by analysing the feeding habits,
selection of prey, transportation of energy, and nutrients. Methods and habits of
food intake are highly related to internal and external morphology of the organism
(Cailliet et al. 1986).

Frey (1971) states that the young flatfish settle on the bottom, eat small crus-
taceans, polychaetes, molluscs and fish, but, as they grow, they eat larger food
items of the same groups. In this paper, more than 91.5% of the crustacean,
Pleuroncodes planipes (44.8%) are the food intake of H. stomata on the Pacific
coast of Baja California.

Allen (1982) found that bigmouth sole, H. stomata and California halibut, Par-
alichthys californicus eat mysids, gammarideans and amphipods. He did not men-

107

DIETARY ANAYLSIS OF HIPPOGLOSSINA OFF BAJA

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108 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

tion, however, that they eat red crab and stomatopods as well, possibly because
his samples were taken in shallower waters. Also Allen (op. cit) established 3
groups according to length: A, within the range of 6.3 to 10.0 cm; B, 11.4 to
18.9 cm and C, 19.2 to 30.8 cm. The first and second group consisted of immature
fish and the main food intake were mysids and gammarideans. He also mentioned
that most of the food was taken from the bottom. In the present paper the size of
the fish could be compared to groups A and B, but here they prefer to eat anomurs
and stomatopods.

Haig in 1955 (in Yany 1977) mentioned that Pleuroncodes monodon is found
on the coast of Chile which spans to Ancud, and Pleuroncodes planipes appears
on the Mexican coast off Baja California. In the study area P. planipes was found
between 24° and 27°N latitude, although it was more abundant at 27°N (Aurioles-
Gamboa 1995). According to Yany et al. (1977), Hippoglossina macrops has as
preferred food the crustaceans, “‘langostino amarillo,’? Cervimunida johni in San
Antonio, Punta Gallo, Laguna Verde, Concon, Quintero and Papudo; and Pleu-
roncodes monodon in Mejillones, Chile (Tomicic 1973 in Yany et al. 1977). This
could indicate a close trophic relationship with similar taxa between the feeding
habits of these flatfish representative of the Galatheidae family, which could be
due to the distribution and abundance of these species. In either case, when the
red crab is abundant in the coastal areas of Mexico and Chile, flatfish feed pref-
erentially on this resource and on other additional groups when red crabs are
scarce.

The main food source for H. stomata in Mexico is the red crab, Pleuroncodes
planipes, and for H. macrops in Chile, the closely related P. monodon, due to the
great abundance of these crustaceans. However, to the south of the 27th North
parallel, Hemisquilla ensigera californiensis, which is less abundant than the red
crab, is always found in the stomach content of H. stomata together with other
species.

Acknowledgments

This study was partially supported by the ‘‘Consejo Nacional de Ciencia y
Tecnologia de México,”’ grant: P22OCCOR880518, by the “‘Universidad Nacional
Auténoma de México” for providing the R/V “‘E] Puma”’ from 1988 to 1991, by
the “Instituto de Ciencias del Mar y Limnologia’’ for the analysis of the infor-
mation, and by the ‘‘Centro de Investigaciones Biolégicas del Noroeste,’’ which
processed the raw material.

Literature Cited

Allen, M. J. 1982. Functional structure of soft bottom fish communities of the southern California
shelf. PhD dissertation, Univ. Calif. San Diego, La Jolla, Ca. 577 pp. (Univ. Microfilm Inst.
Ann Arbor, MI. ref. 830091).

Aurioles-Gamboa, D. 1995. Distribucién y abundancia de la langostilla bent6nica (Pleuroncodes pla-
nipes) en la plataforma continental de la costa oeste de Baja California. In Aurioles-Gamboa,
D. y E. E Balart (eds). La Langostilla: Biologia, Ecologia y Aprovechamiento. Centro de
Investigaciones Bioldgicas del Noroeste, S.C. 59-78.

Aurioles, D., C. Fox, E Sinsel and G. Tanos. 1984. Prey of the California sea lion (Zalophus califor-
nianus) in the Bay of La Paz, Baja California Sur, México. J. Mammal. 65:519-521.

Banner, A. H. 1948a. A taxonomic study of the Mysidacea y Euphausiacea (Crustacea) of the North-
eastern Pacific. Part I. Trans. Royal Canada Inst. (26): 347 pp.

DIETARY ANAYLSIS OF HIPPOGLOSSINA OFF BAJA 109

. 1948b. A taxonomic study of the Mysidacea y Euphausiacea (Crustacea) of the Northeastern
Pacific. Part II. Trans. Royal Canada Inst. (27):65—1235.

Berdegué, A. J. 1956. Peces de importancia comercial en la costa noroccidental de México. Dir. Gral.
Pesca e Industrias conexas. Cop. Fon. Pisc. Rural. Secretarfa de Marina. 345 pp.

Brusca, R. C. 1980. Common intertidal invertebrates of the Gulf of California. 2nd Edition. The
University of Arizona Press. Tucson, Arizona. 513 pp.

De Buen, FE 1961. Peces Chilenos. Estaci6n de Biologia Marina de Montemar, Chile. Rev. Bidl.
Marina, 1:1—52.

Cailliet, M. G., M. S. Love and A. W. Ebeling. 1986. Fishes: a field and laboratory manual on their
identification and natural history. Wadsworth Publishing Co. USA. 194 pp.

Eschmeyer, N. M., E. S. Herald and H. Hammann. 1983. A field guide to Pacific Coast Fishes of
North America. Houghton Mifflin Co., Boston, MA. 336 pp.

Frey, H. W. 1971. California’s living marine resources and their utilization. State Calif. Res. Ag. Dep.
Fish and Game. 61-69.

Goldberg, S. R. 1982. Seasonal spawning cycles of two California flatfishes, Pleuronichthys verticalis
(Pleuronectidae) and Hippoglossina stomata (Bothidae). Bull. Mar. Sci. 32(1):347—350.

Haig, J. 1955. The Crustacean Anomura of Chile, Reports of Lunds Univ. ARSSKR, 51(12):1—60.

Leonard, S. B. 1971. Larvae of the Fourspot Flounder, Hippoglossina oblonga (Pisces: Bothidae),
from the Chesapeake Bight, Western North Atlantic. Copeia, 4:677—681.

Martinez-Munoz, M. A. y Ramirez-Cruz, J. C. 1992. Distribuci6n y abundancia de pleuronectiformes
(TELEOSTEID), en la costa occidental de Baja California Sur, México. Tesis de Licenciatura.
Univ. Nal. Aut6n. México, Fac. de Ciencias. 133 pp.

Pinkas, L., M. S. Oliphant y I. L. K. Iverson. 1971. Food habits of albacore bluefin tuna and bonito
in California waters. Calif. Fish and Game, Fish. Bull. 152, 105 pp.

Ramirez-Murillo, R. 1995. Edad y crecimiento de Hippoglossina stomata Eigenmann & Eigenmann,
1890 (Pisces:Bothidae) en la costa occidental de Baja California Sur, México. Tesis Profesional.
U.M.S.N.H. 48 pp.

Roedel, P- M. 1953. Common ocean fishes of California Coast. Calif. Dept. Fish and Game. Fish
Bull., (91):1-184.

Tomicic, K. J. 1973. Alimentacién de Hippoglossina macrops Steindachner en Mejillones (Pisces,
Bothidae). Not. Mens. Mus. Nac. Hist. Nat., Santiago 205:3-7.

Yany, G. G., C. Moreno y P. Ramirez. 1977. Alimentacion de Hippoglossina macrops Steindachner
1876 (Pisces: Bothidae), en la zona de Valparaiso. Cienc. y Tec. del Mar, Cona 3:23—36.

Accepted for publication 29 December 1997.

SEM and Histological Evidence of Enlarged Nephridial Papillae in
Loandala Monro (Polychaeta: Pilargidae)

Sergio I. Salazar- Vallejo

Depto. Ecologia Acudtica, ECOSUR, Apdo. Postal 424
Chetumal QR 77000 MEXICO

Loandalia Monro and Parandalia Emerson & Fauchald are two closely allied
pilargid genera. Both have a rather cylindrical body with reduced parapodia an-
teriorly and enlarged parapodia posteriorly. The prostomial appendages are also
similar since they both lack antennae and have bifid, often biarticulated palps.
Setae are also similar; notosetae are simple spines sometimes with one or two
smaller companion setae dorsally and neurosetae are spinulous capillaries.

When establishing Parandalia, Emerson and Fauchald (1971) set the differ-
ences between both genera. Loandalia was restricted to the type-species (L. aber-
rans Monro), described from one specimen collected off Angola which lacks
notopodial spines and has unusually well-developed branchiae in posterior setig-
ers. Parandalia was separated from Loandalia by possessing notospines and lack-
ing branchiae in posterior setigers. These authors noted, however, that Monro
(1936) had described notospines though they did not find any when the type
specimen was examined. The branchiae on Monro’s specimen are unusual since
they are directed ventrolaterally and free from neuropodial lobes. The original
designation of these structures as branchiae has been retained by other authors.

The second species of Loandalia (L. maculata) was described by Intes and le
Loeuff (1975) from several specimens collected off the Ivory Coast. They noticed
the species was intermediate between both genera since it had emergent noto-
spines and branchiae in posterior setigers. It also had an emergent ventral spine
in setiger 1. These authors noted that the branchiae of L. maculata were smaller
and started more posteriorly (setiger 50; body length 50 mm) than in L. aberrans
(setiger 33; body length 35 mm). Salazar-Vallejo (1987) described the third spe-
cies, L. riojai, from several specimens collected off Western Mexico. It has no-
tospines from setiger 7 and branchiae from about setiger 22 (body length 59 mm),
but it lacks emergent ventral spines in setiger 1. The fourth species, L. salazar-
vallejoi, was described by de Leén-Gonzalez (1991), from three specimens col-
lected off Western Baja California. It has notospines from setigers 10—13 and
branchiae from setigers 31—40 (body length 67 mm); this species also lacks any
emergent ventral spines in setiger 1.

Thus, in the above species the presence of emergent spines in anterior neuro-
podia cannot be used to set apart Loandalia Monro from Parandalia Emerson &
Fauchald. Therefore, the only distinguishing feature is the presence of ventrolat-
eral branchiae in Loandalia (Salazar-Vallejo 1990).

Branchiae have been employed in polychaete taxonomy to set apart closely
allied genera. Although there are some arguments against branchiae as a generic
character (Orensanz 1990; Fauchald 1992), its utility still has some support. How-
ever, if these enlarged ventrolateral structures were nephridial papillae instead of

110

NEPHRIDIAL PAPILLAE IN LOANDALIA 111

; os ay ) a a ees
Fig. 1. SEM of a posterior fragment of Loandalia riojai. A. Panoramic view of the ventral portion;
B. Close-up of neurosetae (the oblique thread is cotton); C. Close-up of closed nephridial papillae; D.
Close-up of open nephridial papillae (scale in D is the same as in C).

branchiae, then they could not be used to separate these two genera. Since some
nephridial hypertrophy is associated with reproductive activity or with sexual
maturity (Schroeder & Hermans 1975), nephridial development cannot be relied
upon as a discriminating feature. An early description of enlarged nephridial pa-
pillae was provided by Moore (1910:369; Pl. 31, Fig. 60) when he described
Polynoe (?) renotubulata. This species was later moved to a new genus, Bathy-
moorea, by Pettibone (1967) due in part to its extended nephridial papillae. This
Research Note presents SEM and histological evidence that the ventrolateral struc-
tures in Loandalia Monro are nephridial papillae and not branchiae.

Posterior fragments of Loandalia riojai Salazar-Vallejo were prepared accord-
ing to standard methods for SEM and for histological analysis; some modifications
were employed (Sosa-Rodriguez, 1993) from standard Hematoxylin and Eosin
techniques. SEM analysis was performed in the Electronic Microscopy Unit of
the Instituto de Biologia, UNAM. The histological process was performed in the
Laboratory of Invertebrates, Facultad de Ciencias, UNAM. All photographs were
processed in the Photography Lab. of ECOSUR.

In ventral view, nephridial papillae can be seen clearly set off from neuropo-
dium (Fig. 1A); each neuropodium is larger than the papillae and clearly distin-
guished by the presence of neurosetae which arise from setal bundles containing
2—3 setae each (Fig. 1B). If seen from their tip, nephridial papillae appear either

112 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Fig. 2. Cross sections of posterior segments of Loandalia riojai. A. Anterior section without
nephridial papillae; B. More posterior setiger with enlarged nephridial papilla (indicated by an arrow);
C. Close-up of sections with nephridial ciliated funnel; D. Same, in another section; E. Close-up of a
section of the enlarged nephridial papilla; F Same, in another section (Scales: A 150 wm; F 25 wm;
A and B are at the same scale; C—F are at the same scale).

closed (Fig. 1C), or have a distal nephridiopore opening (Fig. 1D). Since the
distal pore might be an artifact of the dehydration process, histological inspection
of the internal structure was employed to reveal whether these were branchiae or
nephridial papillae.

The papillae are not seen in cross section (Fig. 2A) of anterior segments but
in more posterior setigers, a clearly digitate process emerges separate from the
neuropodium (Fig. 2B). Throughout the slide series, some tissue sections show a
circular ciliated structure that corresponds with the nephridial funnel and is exactly

NEPHRIDIAL PAPILLAE IN LOANDALIA Li3

at the end of the lateral muscular bundles (Figs. 2C, D). More posterior slides
show that the enlarged papillae are hollow (Figs. 2E, F). Some major blood ves-
sels can be seen in the tissue but there are no blood vessels associated with the
papillae so they cannot be branchiae.

Without true branchiae, the presence of enlarged nephridial papillae cannot be
employed to separate Loandalia from Parandalia. Thus the genus Parandalia is
a junior synonym of Loandalia. Since there is one species with gravid females
that lacks enlarged papillae (P. vivianneae Salazar-Vallejo & Reyes-Barragan,
1990), these papillae might be associated only with mature males. If some mature
males lack these papillae, it might represent an alternative to sperm release. Fur-
ther study will be necessary on these worms’ reproductive biology.

Acknowledgments

SEM work was kindly performed by Sara Fuentes and allowed by Hilda Flores,
both from Instituto de Biologia, UNAM. Histological preparations were made
easily by the help of Teresa Sosa, Eva Mufioz and José Luis Bortolini and allowed
by Maria Ana Fernandez, Facultad de Ciencias, UNAM. Photographs were pro-
cessed by Humberto Bahena from ECOSUR. This note was triggered by the
interaction with Thomas Parker, Marine Biology Lab, County Sanitation Districts,
Los Angeles; he also provided a complete ms on his proposal to synonymize two
species of Parandalia. Careful reviews by two referees and by the editor improved
the clarity of this note. The original regard of the ventrolateral branchiae in Loan-
dalia as peculiar structures comes directly from Marian H. Pettibone (1986 in a
letter); I’m glad she is right, again. Partial funding for this publication was pro-
vided by CONACYT (4120-P).

Literature Cited

de Leén-Gonzalez, J. A. 1991. Poliquetos de fondos blandos de la costa occidental de Baja California
Sur, México, 1. Pilargidae. Cah. Biol. Mar. 32:311—321.
Emerson, R. R., and K. Fauchald. 1971. A revision of the genus Loandalia Monro with description
of a new genus and species of pilargiid polychaete. Bull. So. Cal. Acad. Sci. 70:18-—22.
Fauchald, K. 1992. A review of the genus Eunice (Polychaeta: Eunicidae) based upon type material.
Smithson. Contr. Zool. 523:1—422.

Intes, A., and P. le Loeuff. 1975. Les annélides polychetes de Cote d’Ivoire, 1. Polychétes errantes—
compte rendu systématique. Cah. ORSTOM, sér. Océanogr. 13:267—321.

Monro, C. C. A. 1936. Polychaete worms, 2. Discovery Rep. 12:59-198.

Moore, J. P. 1910. The polychaetous annelids dredged by the U.S.S. “‘Albatross”’ off the coast of
Southern California in 1904: 2. Polynoidae, Aphroditidae and Segaleonidae (sic). Proc. Acad.
Nat. Sci. Phila. 62:328—402.

Orensanz, J. M. 1990. The eunicemorph polychaete annelids from Antarctic and Subantarctic seas,
with addenda to the Eunicemorpha of Argentina, Chile, New Zealand, Australia and the South-
ern Indian Ocean. Antarctic Res. Ser. 52:1—183.

Pettibone, M. H. 1967. Some bathyal polynoids from Central and Northeastern Pacific (Polychaeta:
Polynoids). Proc. U.S. Natl. Mus. 121(3575):1-15.

Salazar-Vallejo, S. I. 1987. Pilargidae (Annelida: Polychaeta) de México: Lista de especies, nueva
especie y bio(geo)grafia. Cah. Biol. Mar. 27:193—209.

. 1990. Redescriptions of Sigambra grubii Miiller, 1858 and Hermundura tricuspis Miller,

1858 from Brazil and designation of neotypes (Polychaeta: Pilargidae). J. Nat. Hist. 24:507—

S17.

, and M. P. Reyes-Barragan. 1990. Parandalia vivianneae and P. tricuspis (Miller), two es-
tuarine polychaetes (Polychaeta: Pilargidae) from Eastern Mexico. Rev. Biol. Trop. 38:87—90.

Schroeder, P. C., and C. O. Hermans. 1975. Annelida: Polychaeta. Pp. 1-213 in Reproduction of marine

114 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

invertebrates, Vol. 3. Annelids and Echiurans. (A. C. Giese and J. S. Pearse, eds.), Academic,
New York.

Sosa-Rodriguez, T. 1993. Estudio histolégico del poliqueto pelagico Alciopina parasitica (Claparéde
& Panceri, 1867). Tes. Prof., Fac. Ciencias, UNAM, México, 45 pp.

Accepted for publication 29 December 1997.

Status of Beavers (Castor canadensis) in Valle de Mexicali, México

Eric Mellink and Jaime Luévano

Centro de Investigacion Cientifica y de Educaci6én Superior de Ensenada,
B.C. Apartado Postal 2732, Ensenada, Baja California, México!

Abstract.—To determine the current status of beavers (Castor canadensis) in Valle
de Mexicali, Mexico, we surveyed the area in late 1995 and early 1996. We found
evidence of current presence of beavers at 20 sites; 11 additional sites had evi-
dence of past use. Most sites were along the Rio Colorado. Population levels of
beavers in the area are highly variable and depend on extraordinary water releases
through the Rio Colorado.

Resumen.—Con el fin de determinar el estado del castor (Castor canadensis) en
el Valle de Mexicali realizamos prospecciones a finales de 1995 y principios de
1996. Encontramos evidencias de presencia actual de castor en 20 sitios; otros 11
sitios tenfan evidencias de uso anterior. La mayoria de estos sitios se encontraban
a lo largo del Rio Colorado. Las poblaciones de castores en esta regi6n son
altamente variables y dependen de las aportaciones extraordinarias de agua del
Rio Colorado.

The Rio Colorado and tributaries historically had abundant water and main-
tained large stands of willows (Salix gooddingii, S. exigua, and S. hindsiana) and
cottonwoods (Populus macdougalii) along its banks and inundation flats (Wiggins
1980; Ezcurra et al. 1988). These areas supported abundant beavers (Castor can-
adensis; Stone and Rhoads 1905; MacDougal 1906; Mearns 1907; Pattie 1831).
The watercourse in the area was changed extensively early in the 20" century as
a requirement for agriculture. This lead from time to time to the near dissapear-
ance of beavers from most of the area (Sykes 1937a, b). Overall, however, beavers
continued to be a typical component of the region (Burt 1938; Dixon 1922; Huey
1964; Leopold 1953). Indeed, some areas that once were unsuitable for beavers
developed suitable habitat as a result of management of water for agriculture
(Dixon 1922; Grinnell et al. 1937; Tappe 1942). Irrigation practices and agricul-
tural development in the Valle de Mexicali intensified in the 1960s, reducing the
extent of wetlands (Mellink 1995). Also, hunting periodically substantially re-
duced beaver populations (Grinnell 1914; Pattie 1831).

The current status of beavers in the Mexican portion of the drainage of the Rio
Colorado was unknown, although it was supposed that they persisted in small
numbers (Ceballos 1985; Ceballos and Navarro 1991). The purpose of this survey
was to determine the extent of the presence of beavers in this area.

Methods

In October and November 1995 we visited all major water bodies in the Valle
de Mexicali. As we had surveyed the Ciénega de Santa Clara in previous years,

'U.S. Mailing address: CICESE; P.O. Box 434844; San Diego, CA 92143.

US)

116 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

we did not visit it at this time. We also interviewed colleagues with ample knowl-
edge of the Ciénega. We inspected 80 sites, and five stretches of the Rio Hardy.
The sites and river sections were surveyed from a car, on foot, or with a kayak.
In all places, we searched for past and current evidence of use by beavers: felled
trees, stumps, branches in the water, dikes, dens, and slides. On 7 February 1996,
we searched for dams or dens, aboard a Cessna 182 airplane, flying over the
central and northern sections of the mexican portion of the Rio Colorado, and
over the Ciénega de Santa Clara.

Results

We found evidence of current occupation by beavers at 20 sites, some of which
had also evidence of past use; 11 other sites had evidence only of past use (Figure
1). Beavers likely occur at some other, unsurveyed, locations in the area. Beavers
were found from Presa Morelos, at the northern border with the United States, to
the Vado de la Carranza, the intersection of the Rio Colorado with the road south
out of Colonia Carranza; in one spot at the end of Canal El Caiman (formerly
Canal Pescaderos), and in the Rio Hardy south of Campo Mosqueda. Evidences
of past use followed the same pattern, and filled in current gaps. Evidence of
former use was found also at two sites at the seldom-watered Canal Médanos,
and local residents informed us about past presence of beavers in Canal Alamo.
This channel had been cleaned a few months prior to our visit, and no evidence
of its past occupation was left.

The places that had only signs of past use by beavers reflect a current contrac-
tion of the area occupied by them, resulting from the drying of the water bodies.
Also, sites with beavers to which we made succesive visits 2—3 weeks apart were
rapidly drying.

Beavers were clearly associated with willows and cottonwoods, in addition to
the water, as elsewhere in the Lower Colorado. On occasions beavers were present
where water was limited to small stagnant pools, or to thin, shallow currents. The
absence of beavers from the Rio Hardy north of Campo Mosqueda, which has
abundant water and where beavers were once common, can be associated with
the lack of willows and cottonwoods; the only trees now present are shruby
tamarisks (mainly Tamarix pentandra). Current existence of beaver dams, as op-
posed to their absence earlier in the century (Leopold 1959), is the result of the
change in the type of watercourses, from a large river to small currents.

Some of the sites occupied by beavers were depressions that resulted from the
construction of a protection levee on the eastern side of the Rio Colorado during
1979-1981 (Sanchez-Ramirez 1990). These depressions, which can be several
meters deep, were surrounded by willows and cottonwoods. In all such holes that
we inspected, we found evidences of activity of beavers, either current or past.

The Ciénega de Santa Clara is a large wetland created and maintained by brine
water from the Wellton-Mohawk Irrigation District, Arizona (Glenn et al. 1992).
Beavers can occupy this type of marsh, when they have willows, as in Mittry
Lake, Arizona (R. Henry, pers. comm.; Todd 1986). However, the Ciénega de
Santa Clara has few trees, mostly restricted to the edges. Moreover, these are not
the beavers’ preferred trees, but western honey mesquites (Prosopis glandulosa
var. torreyana), screwbean mesquites (P. pubescens), and tamarisks (Tamarix ra-

BEAVERS IN MEXICALI 1k lig

115945) 115°30. 115915!
32°45)

ERS MEXICALL

‘SS
SAN LUIS
RIO COLORADO

Fig. 1. Sites with beaver activity in the Valle de Mexicali, México. Circles represent beaver pres-
ence in October-November 1995. Plus signs, sites with evidence of past use by beavers. Numbers
indicate waterbodies, and letters, specific locations: 1 = Canal Médanos, 2= Canal El Alamo, 3 =
Rio Colorado, 4 = Rio hardy, 5 = Canal El Caiman (formerly Canal Pescaderos), 6 = Ciénega de
Santa Clara, A = Presa Morelos, B = Campo Mosqueda, and C = Vado de la Carranza.

mosissima) (Zengel et al. 1995), which explains why neither we nor colleagues
who have worked in the area have seen any evidence of beavers.

In two cases, beavers had cut stems of young tamarisks, and in two sites they
seemed to be relying exclusively on tule roots (Scirpus americanus). Tappe (1942)
considered that tules could be a more important food than commonly considered.
We found them to be used rarely, and in one of the sites with heavy use of tules,
beavers had been using willows until the drying of the steep-sided pool they lived
in left such trees out of reach. Tules seemed, therefore, to be an emergency food.

Some people in the area eat beavers on occasion, but this does not seem to
happen often. In two places, beavers were a nuisance, as they were felling trees
that had been planted or were being cared for. Rather than killing the beavers,
the people in charge protected the trees with old barrels and salvaged metal.

118 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Discussion

Once control of water for agriculture began, flow in natural watercourses was
reduced and the courses themselves suffered major changes. Beavers followed
these changes, and some locations where beavers have been found were suitable
only as a result of watercourse management. The locality of the only museum
specimen from the region of which we are aware, and the locations reported by
Dixon (1922), Grinnell et al. (1937), Leopold (1953), and Tappe (1942), and three
of our sites were all in such newly developed riparian habitat.

The completion of Hoover Dam (in 1935) and Glenn Canyon Dam (in 1963)
caused a severe reduction in water flow through the Rio Colorado, and an ac-
cordingly severe reduction in populations of beavers in the Valle de Mexicali.
Before 1960, beavers were locally abundant, but even then they suffered fluctu-
ations due to dry periods, as in 1934 (Tappe 1942). Between 1960 and 1978,
water in the Rio Colorado south of the border was extremely scarce, and the
beaver population surely was reduced.

Since 1978, there have been some important flow events in the mexican portion
of the Rio Colorado. These flows, especially the one resulting from the 1982—
1983 El Ninio Southern Oscillation (ENSO) event, promoted the development of
riparian vegetation and an increase in the beaver population along the Rio Col-
orado. Elsewhere, waterways that are usually dry (the Alamos and the Médanos,
for example) received plenty of water at this time and, also, beavers.

Information on the Rio Hardy’s water history is difuse. During 1960-1978, it
seems to have had rather stable, deep water, as the area north of Campo Mosqueda
does today. Since 1947, a naturally formed dam near the entrance of the river to
the Gulf of California caused the development of a large wetland, the Rio Hardy
marsh (J.M. Payne, pers. comm.). At least the northern section of this marsh had
abundant willows and cottonwoods. The 1982-1983 ENSO caused the flooding
of a vast area below the protection levee and created a large wetland that joined
the Rio Hardy marsh. A large community of willows and cottonwoods developed,
and, according to riverside inhabitants, beavers were abundant. However, the in-
tense flows of the mid-1980s also eroded the dam (J.M. Payne, pers. comm.), and
when water flow ceased the marsh drained. Later on, the water level in the Rio
Hardy dropped as well.

Water flow was negligible during 1989-1992, but the 1992-1993 river dis-
charges revived some beaver colonies. At the time of our survey, the pools in the
river were drying once more; some colonies had disappeared, and others were
drying rapidly. In November 1995, water levels in the Rio Hardy were lowering
rapidly and only a few beavers remained. Photographs take by us in 1994 contrast
with the 1995 condition. However, during the aerial reconnaissance of February
1996, the Rio Hardy seemed to have a higher water level than during the previous
autumn.

When large amounts of water are released into the Rio Colorado they can
destroy existing beaver dams and carry animals away, sometimes for great dis-
tances. During the 1982-1988 flows, beavers were seen by the fuel dock at the
Estero de Santa Clara, and one was captured on the sandy seashore of Golfo de
Santa Clara, in the Gulf of California (R. Pita and M. J. Sanchez, pers. comm.).

BEAVERS IN MEXICALI je)

These animals were a distance of about 70 Km from the closest colony at that
time, across unsuitable habitat.

Although numbers of beavers in the Valle de Mexicali fluctuate dramatically
and often approach extirpation, it is difficult to give them a legal risk status. The
local subspecies (C. c. frondator, after Hoffmeister 1986) is widespread and has
healthy populations in adjacent areas in the United States, where beavers are often
considered a nuisance, and are controlled accordingly. There is no management
plan for beavers in the valle de Mexicali, and the conservation of the habitat, in
this area is fortuitous and completely marginal to agricultural production. Cur-
rently, beaver habitat is created mostly by rare extraordinary water releases
through the Rio Colorado.

Acknowledgments

This project was financed by the Programa Ambiental Frontera Norte, Instituto
Nacional de Ecologia. Rocio Esquivel and Rodrigo Medellin assisted the funding
process. Robert Henry assisted during early stages of the project. Alberto Tapia-
Landeros, Prisciliano Gonzalez, Enrique Galindo, Jesus Zazueta, Cecilio Lomeli-
Lopez, and several inhabitants of the Valle de Mexicali provided information.
Iriana Zuria, assisted during field work, and Lourdes Méndez and Martin Diaz
provided logistical support. Sandy Lanham (Environmental Flying Services) kind-
ly supported us with the aerial flight. Vicente Ferreira, Eduardo Palacios, Horacio
de la Cueva, Dan Guthrie and several anonymous reviewers made important sug-
gestions. To all of them, our deepest appreciation.

Literature Cited

Burt, W. H. 1938. Faunal relationships and geographic distribution of mammals in Sonora, Mexico.
Misc. Publ. Mus. Zool., Univ. Michigan, 39:1—77.

Ceballos-G., G. 1985. The importance of riparian habitats for the conservation of endangered mammals
in Mexico. U. S. Dep. Agric., For. Serv. Gen. Tech. Rep., RM-120:96—100.

Ceballos, G., and D. Navarro L. 1991. Diversity and conservation of Mexican mammals. Pp. 167—
198, in Latin American mammalogy: history, biodiversity and diversity (M. A. Mares and D.
J. Schmidly, eds.). Univ. Oklahoma, 468 pp.

Dixon, J. 1922. Rodents and reclamation in the Imperial Valley. J. Mamm., 3:136—146.

Ezcurra, E., R., S. Felger, A., D. Russell, and M. Equihua. 1988. Freshwater islands in a desert sand
sea: the hydrology, flora, and phytogeography of the Gran Desierto oases of northwestern
Mexico. Desert Plants, 9:35—44, 55-63.

Glenn, E., P, R. S. Felger, A. Burquez, and D. S. Turner. 1992. Ciénega de Santa Clara: endangered
wetland in the Rio Colorado delta. Nat. Res. J., 32:817—824.

Grinnell, J. 1914. An account of the mammals and birds of the Lower Colorado Valley. Univ. of Calif.
Publ. in Zoology 12(4):51—294.

Grinnell, J., J. S. Dixon, and J. M. Linsdale. 1937. Fur-bearing mammals of California. Univ. California
ress, 777 pp:

Hoffmeister, D. E 1986. Mammals of Arizona. Univ. Arizona Press, 602 pp.

Huey, L. M. 1964. The mammals of Baja California, Mexico. Trans. San Diego Soc. Nat. Hist., 13:

85-168.
Leopold, A. 1953. Round River; from the journals of Aldo Leopold (L. B. Leopold, ed.). Oxford
Univ., 173. pp.

Leopold, A. S. 1959. Wildlife of Mexico: the game birds and mammals. Univ. California Press, 568 pp.

MacDougal, D. T. 1906. The delta of the Rio Colorado. Contrib. New York Bot. Garden, 77:1—16.

Mearns, E. A. 1907. Mammals of the Mexican boundary of the United States; part 1 Didelphidae to
Muridae. Bull. U. S. Nat. Mus., 56:1—530.

120 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Mellink, E. 1995. Status of the muskrat in the Valle de Mexicali and the Delta del Rio Colorado,
México. Calif. Fish and Game, 8:33-38.

Pattie, J. O. 1831. The personal narrative of James O. Pattie of Kentucky. John H. Wood, 269 pp.

Sanchez-Ramirez, O. 1990. Crénica agricola del Valle de Mexicali. Univ. Aut. Baja California, 274 pp.

Stone, W., and S. N. Rhoads. 1905. On a collection of birds and mammals from the Colorado Delta,
Lower California. Proc. Acad. Nat. Sci. Philadelphia 1905:676—690.

Sykes, G. 1937a. Delta, estuary, and lower portion of the channel of the Rio Colorado 1933 to 1935.
Carnegie Inst. Washington Publ., 480: 1-70.

Sykes, G. 1937b. The Colorado delta. Am. Geog. Soc. Publ. 19:1—193.

Tappe, D. T: 1942. The status of beavers in California. Game Bull., Calif. Div. Game and Fish, 3:1—59.

Todd, R. L. 1986. A saltwater marsh hen in Arizona. Ariz. Game and Fish Dep., 290 pp.

Wiggins, I. L. 1980. Flora of Baja California. Stanford Univ., 1025 pp.

Zengel, S. A., V. J. Meretsky, E. P. Glenn, R. S. Felger, and D. Ortiz. 1995. Cienega de Santa Clara,
a remnant wetland in the Rio Colorado delta (Mexico): vegetation distribution and the effects
of water flow reduction. Ecol. Engin. 4:19-—36.

Accepted for publication 7 May 1998.

Re-occurrence of the Threebanded Butterflyfish,
Chaetodon humeralis (Chaetodontidae), with Notes on its
Distribution in Southern California

Daniel J. Pondella, II,' Robert Snodgrass,* Matthew T. Craig,' and Hugh Khim?

'Vantuna Research Group, Moore Laboratory of Zoology,
Occidental College, Los Angeles, California 90041
?11671 Tierra del Sur, San Diego, California 92130-2614
3National Marine Fisheries Service 76 N. King St., Suite 200,
Honolulu, Hawaii 96817

The threebanded butterflyfish, Chaetodon humeralis Ginther 1860, is an eastern
Pacific endemic species whose range has been reported as northern Chile to San
Diego, California, reaching the Galapagos and Cocos Islands (Miller and Lea
1972, Grove and Lavenberg 1997). It is easily distinguishable from the three other
chaetodontid species, C. falcifer, Johnrandallia nigrirostris, and Forcipiger flav-
issimus, found in the eastern Pacific and cannot be confused with any Indo-West
Pacific species. Two juvenile specimens are herein reported from southern Cali-
fornia.

On 1 November 1997, Hugh Khim, a student at the University of California,
San Diego, was free diving at 10 m along the wall of the underwater canyon in
the La Jolla marine reserve. While observing other juvenile fish hiding along the
one-meter high siltstone wall, he discovered a juvenile threebanded butterflyfish,
approximately 4 cm total length (TL). This fish was found some three weeks later
by Khim and Robert Snodgrass who videotaped it; it had not moved from its
original location. Water temperatures in La Jolla at this time and during the pre-
ceding weeks were above 20°C, even at depths exceeding 20 m (R. Mc-
Connaughey, pers. comm.).

In King Harbor, Redondo Beach, California, on 12 December 1997, while con-
ducting routine ichthyotransects with Matthew Craig, Daniel Pondella of the Van-
tuna Research Group (VRG) at Occidental College observed a solitary three-
banded butterflyfish at the end of the west breakwater (latitude 33°50.5 N, lon-
gitude 118°23.7 W). That day on a subsequent dive it was found at the same
location and captured with a hand net. The depth of capture was 10 m and the
water temperature was 17.3°C, the ambient temperature of Santa Monica Bay at
the time. This specimen, 46.5 mm TL, was photographed (Fig. 1), preserved and
given to the Marine Vertebrates Collection at the Scripps Institution of Ocean-
ography in La Jolla (SIO 98-23).

The last verified collection or known observation of C. humeralis in California
was during a warm-water period approximately 140 years ago (Hubbs and Rech-
nitzer 1958). During the Pacific Railroad Survey, Lt. W. P. Trowbridge collected
two specimens from San Diego (USNM 3170); however, these fish were not
catalogued until after Girard’s work on these collections (1854; 1858) and were
not included in books of California fishes (Barnhart 1936, Roedel 1948, 1953).
Hubbs and Rechnitzer (1958, p. 279) note:

121

122 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Fig. 1. Left lateral view of the threebanded butterflyfish, Chaetodon humeralis, (38.6 mm SL,
S1098-23) captured in King Harbor, Redondo Beach, California on December 12, 1997. Photograph
by Daniel J. Pondella, II.

The low catalog number (3170) indicates that the specimens were in fact
entered in the collection nearly 100 years ago. Lt. W. P. Trowbridge was one
of the most effective of the West Coast collectors on the Pacific Railroad
Surveys. Somehow the species escaped inclusion in Girard’s reports on the
fishes collected by these surveys. Presumably the specimens came to light
after the bulk of the collections had been studied and cataloged, for the
number is higher than those recorded for the species reported by Girard. In
this connection it may be noted that Girard (1858: 338) referred to other
specimens from San Diego that had become ‘“‘mislaid in the moving of the
Smithsonian collections from one end of the building to another a few months
since.’’ Some slight doubt regarding the validity of the San Diego record can
not be dispelled, but we believe that C. humeralis is to be added to the list
of tropical fishes that occurred at San Diego during the warm period a century
ago.

A trip by Matthew Craig to the National Museum of Natural History found the
specimens were catalogued as described by Hubbs and Rechnitzer (1958) with
the locality listed simply as “‘San Diego’’. The specimens (68.9, 89.2 mm TL,
Table 1) were in good condition. The two fish observed in 1997 are fairly small,
allowing inferences into settlement processes. Two possibilities are that they either
recruited from the ichthyoplankton or rafted into these reefs. The USNM speci-
mens are much larger than the 1997 specimens.

Although previously collected as far north as the San Benito Islands (SIO 84-

RE-OCCURRENCE OF THREEBANDED BUTTERFLYFISH IN CALIFORNIA [25

Table 1. Counts and measurements for the three museum specimens of threebanded butterflyfish,
Chaetodon humeralis, from southern California. Lengths given in millimeters.

Specimens
Counts and measurements SIO98-23 USNM3170 USNM3170

Standard length 38.6 59.9 75.9
Total length 46.5 68.9 89.2
Dorsal fin elements XIII, 20 XIII, 18 XII, 19
Anal fin elements a 17: Ill, 16 Ill, 16
Lateral line scales 32 34 35
Pectoral rays (1) 16 Ig) 16

227), the typical northern range does not extend past Magdalena Bay (eg. SIO
62-105, SIO 64-55 and R. N. Lea, pers. comm.). The specimen found in King
Harbor, Redondo Beach, California represents the known northern limit of this
species, an extension of some 150 kilometers from the historic San Diego locality.

Much attention has been given to the warming trends of coastal waters along
our coasts of the Americas beginning in the mid 1970’s (Hayward 1997) and
recently exasperated by the 1997-98 major El Nino Southern Oscillation (ENSO)
event. It is probable that the recruitment of these two juvenile individuals is related
to this event.

Various expatriated fishes to the Southern California Bight with the northern
limits of their ranges normally at Magdalena Bay, or occasionally at the San
Benito Islands, have been noted since the shift from Oregonian dominated fauna
to a San Diegan fauna beginning with the 1978-79 ENSO (eg. Brooks 1987, Lea
and Fukuhara 1991, Lea and Rosenblatt 1992, Lea and McAlary 1994, Lea and
Walker 1995, Pondella 1997). The long-term success of these individuals and the
continued presence of these species in the Southern California Bight are uncertain.
However, as indicators of environmental change (Radovich 1961, Mearns 1988,
Stephens et al. 1988) the recruitment of tropical and subtropical (Panamic) species
in the temperate waters of southern California is strong evidence of the current
ENSO strength.

Acknowledgments

We are indebted to the curatorial assistance of C. Klepadio and H. J. Walker
at the Scripps Institution of Oceanography and S. Jewitt and J. T. Williams at the
Smithsonian Institution National Museum of Natural History. We would like to
acknowledge the critical review and assistance of R. N. Lea, H. J. Walker and J.
S. Stephens, Jr. and information provided by R. McConnaughey.

Literature Cited

Barnhart, P. S. 1936. Marine Fishes of Southern California. University of California Press, Berkeley,
California. iv + 209.

Brooks, A. J. 1987. Two species of Kyphosidae seen in King Harbor, Redondo Beach, California.
Calif. Fish and Game. 73:49-61.

Grove, J. S. and R. J. Lavenberg. 1997. The Fishes of Galapagos Islands. Stanford University Press,
Stanford, California. XLIV + 863 p.

Hayward, T. L. 1997. Pacific Ocean climate change: atmospheric forcing, ocean circulation and eco-
system response. TREE. 12(4):150—154.

124 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Hubbs, C. L. and A. B. Rechnitzer. 1958. A new fish, Chaetodon facifer, from Guadalupe Island, Baja
California, with notes on related species. Sci., Proc. Calif. Acad. 29(8):273-313.

Girard C. E 1854. Observation upon a Collection of Fishes Made on the Pacific Coast of the United
States, by Lieut. W. P. Trowbridge, U.S.A., VII (no. 4). Proc. Acad. Nat. Sci. Phila. pp. 142—
156.

. 1858. Fishes of the Pacific Railroad Survey. Reports of explorations and surveys, to ascertain
the most practicable and economical route for a railroad from the Mississippi River to the
Pacific Ocean. House of Rep. Ex. Doc. No. 91. 400 pp., 76 pls.

Lea, R. N. and L. Fukuhara. 1991. The Gulf coney, Epinephelus acanthistius, from the marine waters
of southern California. Bull. S. Calif. Acad. Sci. 90(2):80—82.

Lea, R. N. and R. H. Rosenblatt. 1992. The Cortez grunt, Haemulon flaviguttatum, recorded from two
embayments in southern California. Calif. Fish and Game, 78:163—165.

Lea, R. N. and F McAlary. 1994. Occurrence of the swallow damselfish, Azurina hirundo, from islands
off southern California. Bull. S. Calif. Acad. Sci. 93:43—44.

Lea, R. N. and H. J. Walker, Jr. 1995. Record of the bigeye trevally, Caranx sexfasciatus, and Mexican
lookdown, Selene brevoorti, with notes on other carangids from California. Calif. Fish and
Game. 81:89-95.

Mearns, A. J. 1988. The “‘odd fish’’: unusual occurrences of marine life as indicators of changing
ocean conditions. Pp. 137-176, in Marine Organisms as Indicators. (D. E Soule and G. S.
Kleppel, ed.), Springer-Verlag, New York. xii + 342 p.

Miller, D. J. and R. N. Lea. 1972. Guide to the coastal marine fishes of California. Calif. Dept. Fish
and Game, Fish Bull. (157):1—249.

Pondella, D. J., Il. 1997. The first occurrence of the Panamic sergeant major, Abudefduf troschelii
(Pomacentridae), in California. Calif. Fish and Game. 83(2):84—86.

Radovich, J. 1961. Relationships of some marine organisms of the northeast Pacific to water temper-
atures, particularly during 1957 through 1959. Calif. Dept. Fish and Game, Fish Bull. (112):1—62.

Roedel, P. M. 1948. Common Marine Fishes of California. Calif. Dept. Fish and Game, Fish Bull.
(68):1-153.

. 1953. Common Ocean Fishes of the California Coast. Calif. Dept. Fish and Game, Fish Bull.
(91):1-184.

Stephens, J. S., Jr, J. Hose, and M. S. Love. 1988. Fish assemblages as indicators of environmental
change in nearshore environments. Pp. 91—105, in Marine Organisms as Indicators. (D. E Soule
and G. S. Kleppel, ed.), Springer-Verlag, New York. xii + 342 p.

Accepted for publication 30 July 1998.

INDEX TO VOLUME 97

Araeoschizus agustinus, new species, 90
Araeoschizus blomi, new species, 93

Borgon-Gonzalez, Dora J., see Elena Solana-Arellano

Brattstrom, Bayard H: Strategies of Predator Attacks on the Schooling Fish, Selar
crumenophthalmus, in Academy Bay, Soccoro Island, Islas Revillagigedo,
Mexico, 76

Bursey, Charles, R., see Stephen R. Goldberg

Campos, Alma Rosa de, see Ernesto Campos

Campos, Ernesto and Alma Rosa de Campos: Distribution and Taxonomic Re-
marks for Five Crab Species of the Family Grapsidae (Crustacea: Sesarminae
and Varuninae) of the Mexican Pacific, 96

Constantine, Denny G: Range Extensions of Ten Species of Bats in California,
49

Craig, Matthew T., see Daniel J. Pondella, I

Diaz-Castaneda, V. and V. Rodriguez-Villanueva: Polychaete Fauna from San
Quintin Bay, Baja California, Mexico, 9

Echavarria-Heras, Hector, see Elena Solana-Arellano
Figueroa-Carranza, Ana-Luisa, see Juan-Pablo Gallo-Reynoso

Gallo-Reynoso, Juan-Pablo and Ana-Luisa Figueroa-Carranza: Cetaceans of Isla
De Guadalupe, Baja California, Mexico, 33

Goldberg, Stephen R., Charles R. Bursey amd Mei Q. Wu: Composition of the
Helminth Community of a Montane Population of the Coastal Whiptail,
Cnemidophorus tigris multiscutatus (Sauria: Teiidae) from Los Angeles
County, California, 82

Hartney, Kristine Behrents and Lusine Tumyan: Temporal Changes in Diet and
Foraging Habitat of California Killifish (Fundulus parvipinnis) in Marina del
Rey, California, |

Khim, Hugh, see Daniel J. Pondella, I
Luevano, Jaime, see Eric Mellink

Martinez-Mufnoz, Marco A., see Ricardo R. Murillo

Mellink, Eric and Jaime Luevano; Status of Beavers (Castor canadensis) in Vaile
de Mexicali, Mexico, 115

Murillo, Ricardo R., A. A. Ortega-Salas, and Marco A. Martinez-Munioz: A Di-
etary Analysis of Hippoglossina stomata Eigenmann and Eigenmann, 1980
(Pisces: Bothidae) along the Western Coast of Baja California, Mexico, 104

126 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES

Ortega-Salas, A. A., see Ricardo R. Murillo

Papp, Charles, S: Two New Stenosini Species in the Genus Araeoschizus LeConte
from Baja California, Mexico (Coleoptera: Tenebrionidae), 89

Pondella, Daniel J. I], Robert Snodgrass, Matthew T. Craig, and Hugh Khim: Re-
occurrence of the Threebanded Butterflyfish, Chaetodon humeralis (Chaeto-
dontidae), with Notes on its Distribution in Southern California, 121

Rodriguez- Villanueva, V., see V. Diaz-Castafieda

Salazar- Vallejo, Sergio I: SEM and Histological Evidence of Enlarged Nephridial
Pappillae in Loandalia Monro (Polychaeta: Pilargidae), 110

Snodgrass, Robert, see Daniel J. Pondella, II

Solana-Arellano, Elena, Dora J. Borbon-Gonzalez, and Hector Echavarria-Heras:
A General Allometric Model for Blade Production in Zostera marina, 39

Tumyan, Lusine, see Kristine Behrents Hartney
Wu, Mei Q., see Stephen R. Goldberg
Yohe, Robert M. II: Notes on the Late Prehistoric Extension of the Range for the

Muskrat (Ondatra zibethicus) Along the Ancient Shoreline of Lake Cahuilla,
Coachella Valley, Riverside County, California, 86

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INSTRUCTIONS FOR AUTHORS

The BULLETIN is published three times each year (April, August, and December) and inc!udes articles in English
in any field of science with an emphasis on the southern California area. Manuscripts submitted for publication
should contain results of original research, embrace sound principles of scientific investigation, and present data in
a clear and concise manner. The current AIBS Style Manual for Biological Journals is recommended as a guide
for contributors. Consult also recent issues of the BULLETIN.

MANUSCRIPT PREPARATION

An abstract summarizing in concise terms the methods, findings, and implications discussed in the paper must
accompany a feature article. Abstract should not exceed 100 words.

A research note is usually one to six typewritten pages and rarely utilizes subheadings. Consult a recent issue
of the BULLETIN for the format of notes. Abstracts are not used for notes.

The literature cited: Entries for books and articles should take these forms.

MeWilliams, K. L. 1970. Insect mimicry. Academic Press, vii + 326 pp.

Holmes, T. Jr., and S. Speak. 1971. Reproductive biology of Myotis lucifugus. J. Mamm., 54:452—458.

Brattstrom, B. H. 1969. The Condor in California. Pp. 369-382 in Vertebrates of California. (S. E. Payne, ed.),

Univ. California Press, xii + 635 pp.

PROCEDURE

CONTENTS

Two New Stenosini Species in the Genus Araeoschizus LeConte from Baja
California, Mexico (Coleoptera: Tenebrionidae). Charles S. Papp —_

Distribution and Taxonomic Remarks for Five Crab Species of the Family
Grapsidae (Crustacea: Sesarminae and Varuninae) of the Mexican Pa-
cific. Ernesto Campos and Alma:Rosa de Campos — 3

A Dietary Analysis of Hippoglossina stomata Eigenmann and Eigenmann,
1980 (Pisces: Bothidae) along the Western Coast of Baja California,
Mexico. Ricardo R. Murillo, A. A. Ortega-Salas, and Marco A.
Miartineéz-MUNOZ 02.0.2 ee ee

SEM and Histological Evidence of Enlarged Nephridial Papillae in Loan-
dalia Monro (Polychaeta: Pilargidae). Sergio I. Salazar-Vallejo

Status of Beavers (Castor canadensis) in Valle de Mexicali, México. Eric
Mellink and Jaime Luévano: —.. 220. ee eee eee

Re-occurrence of the Threebanded Butterflyfish, Chaetodon humeralis
(Chaetodontidae), with Notes on its Distribution in Southern Califor-
nia. Daniel J. Pondella, II, Robert Snodgrass, Matthew T. Craig, and
Hugh: Kittin 22.202t.0 le ee

COVER: Araeoschizus agustinus Papp, n. sp.

104

110

115

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