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NOAA TR NMFS SSRF-665

A UNITED STATES DEPARTMENT OF COMMERCE PUBLICATION

►.

V

NOAA Technical Report NMFS SSRF-665

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Larval Fish Survey of Humboldt Bay, California

MAXWELL B. ELDRIDGE and CHARLES F. BRYAN

F?&2i 1973

SEATTLE, WA

December 1972

NOAA TECHNICAL REPORTS National Marine Fisheries Service, Special Scientific Report-Fisheries Series

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Contributions to the life histories of several penaeid shrimps (Penaeidae) along the south Atlantic Coast of the United States. By William W. Anderson. May 1970, iii + 24 pp., 15 figs., 12 tables.

606. Annotated references on the Pacific saury, Colol- abis saira. By Steven E. Hughes. June 1970, iii + 12 pp.

607. Studies on continuous transmission frequency modulated sonar. Edited by Frank J. Hester. June 1970, iii + 26 pp. 1st paper, Sonar target classification experiments with a continuous- transmission Doppler sonar, by Frank J. Hester, pp. 1-20, 14 figs., 4 tables; 2d paper, Acoustic target strength of several species of fish, by H. W. Volberg, pp. 21-26, 10 figs.

608. Preliminary designs of traveling screens to col- lect juvenile fish. July 1970, v + 15 pp. 1st paper, Traveling screens for collection of juvenile salmon (models I and II), by Daniel W. Bates and John G. Vanderwalker, pp. 1-5, 6 figs., 1 table; 2d paper, Design and operation of a canti- levered traveling fish screen (model V), by Dan- iel W. Bates, Ernest W. Murphey, and Earl F. Prentice, 10 figs., 1 table.

609. Annotated bibliography of zooplankton sampling devices. By Jack W. Jossi. July 1970, iii + 90 pp.

610. Limnological study of lower Columbia River, 1967-68. By Shirley M. Clark and George R. Snyder. July 1970, iii + 14 pp., 15 figs., 11 tables.

611. Laboratory tests of an electrical barrier for con- trolling predation by northern squawfish. By Galen H. Maxfield, Robert H. Lander, and Charles D. Volz. July 1970, iii + 8 pp., 4 figs., 5 tables.

612. The Trade Wind Zone Oceanography Pilot Study. Part VIII: Sea-level meteorological properties and heat exchange processes, July 1963 to June 1965. By Gunter R. Seckel. June 1970, iv + 129 pp., 6 figs., 8 tables.

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615. Distribution of fishing effort and catches of skip- jack tuna, Katsuwonus pelamis, in Hawaiian waters by quarters of the year, 1948-65. By Richard N. Uchida. June 1970, iv + 37 pp., 6 figs., 22 tables.

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Continued on inside back cover.

OWMOSP,

"^flifofC^

U.S. DEPARTMENT OF COMMERCE Peter G. Peterson, Secretary

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION Robert M. White, Administrator

NATIONAL MARINE FISHERIES SERVICE Philip M. Roedel, Director

NOAA Technical Report NMFS SSRF-665

Larval Fish Survey of Humboldt Bay, California

MAXWELL B. ELDRIDGE and CHARLES F. BRYAN

SEATTLE, WA December 1972

For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, DC. J0402 - Price 25 cents

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CONTENTS

Page

Introduction 1

Methods 2

Results 2

Environment 2

Species composition 4

Areal distribution 5

Seasonal distribution 6

Discussion 6

Acknowledgments 8

Literature cited 8

Figures

1. Humboldt Bay, Calif., and the five sampling stations 2

2. Sampling boat showing macroplankton sampling apparatus 3

3. Surface ( — ) and bottom ( — ) temperatures recorded in Humboldt

Bay during 1969 3

4. Surface ( — ) and bottom ( — ) salinities recorded in Humboldt

Bay during 1969 3

5. The mean larval fish catch per cubic meter of water samples

collected in each station during 1969 5

6. The number of species offish larvae and juveniles collected

in each station during 1969 6

7. The mean fish catch per cubic meter of water sampled each

month during 1969 6

8. The number of species of fish larvae and juveniles captured each

month during 1969 6

in

Larval Fish Survey of Humboldt Bay, California

By MAXWELL B. ELDRIDGE

National Marine Fisheries Service

Tiburon Fisheries Laboratory

Tiburon, CA 94920

and

CHARLES F. BRYAN

Cooperative Fisheries Unit

Louisiana State University

Baton Rouge, LA 70803

ABSTRACT

As part of a series of investigations of the marine resources of Humboldt Bay, Calif., a larval fish survey was conducted from January to December 1969. Bottom and oblique tows were made at five sampling stations with 1-m plankton nets on alternate biweekly intervals. Thirty-seven species of larval and juvenile fishes representing 17 families were collected. In terms of larval abundance, the dominant fish was the bay goby, Lepidogobius lepidus, followed by Pacific herring (Clupea harengus pallasi). Pacific staghorn sculpin (Leptocottus armatus), longtin smelt (Spirinchus thaleichthys), and the arrow goby {Clerelandia ios). These five species constituted 95% of all larvae captured.

The number of larvae captured increased with increasing distance from the mouth of the Bay. The lowest number of species captured was at a station which experienced the widest range of salinities and temperatures. Peaks of seasonal abundance occurred in January and February and in April and May. Relatively few fish were captured after June. Some notable appearances of offshore spawned fishes were found in Hum- boldt Bay.

INTRODUCTION

Pacific coast estuaries are important spawn- ing and nursery grounds for fishes, but the extent of this utilization has received little attention from fishery scientists. In northern California waters, several biologists have conducted investigations. Porter (1964) studied the larval and juvenile pleuronectids and bothids in the waters adjacent to the entrance of Humboldt Bay, Calif. Further pleuronectid research was carried on when Misitano (1970) captured premetamorphosed and juvenile

English sole (Parophrys vetulus) during the course of his early life history study. Some incidental catches of fish larvae were made in a zooplankton survey recently completed in the northern part of Humboldt Bay (Eichen- berry, 1970). The most current research in- volves a larval cottid study which was begun in the spring of 1971.

This larval fish survey was conducted as part of a series of studies to evaluate the resources of Humboldt Bay. From January to December 1969, an intensive effort was

made to determine the seasonal and areal distribution of the larval fishes.

METHODS

Humboldt Bay is located on the north coast of California (Fig. 1). It is 14 miles long, shallow with extensive mudflats, and is mostly bordered by marshlands and sandy beaches. Areata and South Bays are uniform- ly shallow and unnavigable outside the narrow channels, except at high tide. Limited fresh- water entry is provided by one small river, three creeks, and minor tributaries.

Five sampling stations, each 153 m (500 ft) long, were selected (Fig. 1). Stations 1 and 4 were similar in depth (5-8 m) and were lo- cated in major drainage channels adjoining expansive eelgrass mudflats. Station 2, ad- jacent to a rock jetty, experienced the strong- est tidal currents and was the deepest station (12-15 m). Station 3 was relatively shallow

(3-5 m) and bordered by a gently sloping sandy beach. Station 5 was the shallowest (2-3 m) and experienced the greatest varia- tion in salinity and temperature.

An attempt was made to sample the entire water column at each station, making alter- nate bottom and oblique tows at biweekly intervals. A 1-m plankton net of No. 0 mesh (aperture size 0.57 mm) was used with a centrally located flowmeter. For bottom samples, a macroplankton sled (Fig. 2) was towed at 1-3 knots. The sampling gear was retrieved, using a variable-speed winch ap- paratus powered by a 4-hp engine with a 4-speed automobile transmission.

Larval and juvenile fishes were collected in 118 tows over a 12-month period. All samples were fixed and held in 5% formaldehyde in sea- water. Fishes were sorted, identified, enumer- ated, and measured, using an ocular microm- eter mounted in a stereozoom dissecting micro- scope. Identifications were made with the assist- ance of E. H. Ahlstrom (personal communica- tion) and by using several keys and descriptions, the most useful of which were: Ahlstrom (1965), Bolin (1944), Breder and Rosen (1966), Budd (1944), Clothier (1950), Hart and McHugh (1944), Hickman (1959), Jones (1962), Orcutt (1950), and Orsi (1965).

Surface and bottom temperatures and salinities were taken with each sampling. Temperatures were recorded using a standard nonreversing mercury thermometer while salinities were determined with an induc- tion salinometer in the laboratory.

RESULTS

Environment

Figure 1. — Humboldt Bay, Calif., and the five sampling stations.

In general, vertical similarities in temper- ature and salinity reflect the extent of mixing and low freshwater inflow into the Bay (Fig. 3 and 4). Water temperatures from January to December 1969, ranged from 7.5° to 19.6°C (Fig. 3). The temperature began to increase in February and reached a maximum in late May, remaining high until September. Stations 1, 2, and 3 exhibited the lowest over- all combined surface and bottom temperature means (11.4°, 11.0°, and 11.3°C, respectively), while stations 4 and 5 had relatively high

Figure 2. — Sampling l>oat showing macroplankton sampling appartus.

-

t

STATION 1

-

^ , - - -_^>— -^rrr*

■"•— -

-

^<- ~^—

STATION 2

1

^*"

STATION ]

-

-

-

STATION 4

-

-

S^^ ^"^<,

-

-

—I—

STATION S

1 1 1 1 1 1 1 V~ f-

1

-

JIN MB MAR APR MAT IUN I II I AOG SEP OCT NOV DEC

_i 1 1.

J I I 1 1 1 1 1_ — -4 -f-

' ■ i i i • i T u i i ' i ii ii i ii i i ii i: ■ i c n r i unu i

JAN I t H MAR APR MAT IUN JUL I II G SEP OCT NOV 0 E C

Figure 3. — Surface (— ) and bottom ( — ) temperatures Figure 4. -- Surface ( — ) and bottom ( — ) salinities

recorded in Humboldt Bay during 1969. recorded in Humboldt Bay during 1969.

overall means (12.8° and 13.3°C, respective- ly). The greatest fluctuation in bottom and surface salinities occurred between January and May (Fig. 4), then they stabilized through- out the remainder of the year. Because station 5 was located within the mouth of a fresh- water tributary, the greatest range and vertical variation in salinities were found here. The overall mean for all stations was 31.5 & and the range 8.5-34.1%.

Species Composition

Thirty-seven species of larval and juvenile fishes representing 17 families were collected during the 12-month sampling period (Table 1). Of these, nine forms were not identifiable beyond family and two only to superorder.

Two were classified to genus and 24 to species. The total catch of larvae and juveniles was 9,766, yielding an average of 0.13 larvae per cubic meter of water sampled.

The most speciose family was the Cottidae with six species. Only two were identifiable; the rest were present in too few numbers or were not found in developmental series to allow identification. In terms of abundance, the bay goby, Lepidogobius lepidus, dominated the catch and Pacific herring, Clupea harengus pallasi, were almost as abundant; together they comprised 82% of the total catch. The bay goby, Pacific herring, Pacific staghorn sculpin (Leptocottus armatus), longfin smelt {Spirinchus thaleichthys), and the arrow goby (Clevelandia ios) constituted 95% of all larvae collected.

Table 1. Species, month, size and numbers offish larvae and juveniles collected in Humboldt Bay, Calif.

No.

of

No.

of

Size

larvae

juveniles

Month collected

Taxon

Common name

range

(mm)

OT1

BT2

OT1

BT2

Clupeidae:

Chtpea harengus pallasi

Pacific herring

4-32

2,814

864

3

278

Jan. -May

Engraulidae:

Engraulis mordax

Northern anchovy

5-37

1

3

3

12

Mar., Aug., Sept.

Dec.

Osmeridae:

Hyponiesus pretiosus

Surf smelt

23-51

-

-

10

23

Nov. -Mar.

Spirinchus stark si

Night smelt

55-69

-

-

25

Jan.

Spirinchus thaleichthys

Longfin smelt

4-51

525

186

--

2

Jan. -Dec.

Osmerid

Unknown

4-13

20

140

--

-

Mar. -June

Sciaenidae:

Cynoscion nobilis

White seabass

4-6

1

8

--

-

Jan., Dec.

Myctophidae:

Stenobrachius leucopsarus

Northern lampfish

3-5

4

3

-

-

Jan. -Mar., May

Tarltonbeania crenularis

Blue lampfish

4-7

4

2

-

-

Sept. -Nov.

Gonostomatidae:

Cyclothone acclinidens

Benttooth

bristlemouth

4

1

-

-

-

Dec.

Gobiidae:

Lepidogobius lepidus

Bay goby

3-33

790

3,260

3

19

Apr. -Sept.

Eucyclogobius newberryi

Tidewater goby

10-12

-

-

2

--

Nov.

Clevelandia ios

Arrow goby

3-6

41

216

-

-

Aug. -Dec.

Scorpaenidae:

Sebastodes spp.

Rockfish

4-6

6

5

-

-

Dec. -Mar.

Hexagrammidae:

Hexagrammos decag nun urns

Kelp greenling

8

-

11

-

-

Feb.

Ophiodon elongatns

Lingcod

4-9

2

4

-

-

Jan. -Feb.

Hexagrammid

Unknown

8

-

1

-

-

May

Comparatively few juveniles (386) were captured with 11 species represented. Herring were very numerous making up 73% of the total catch of juveniles (Table 1).

Areal Distribution

Larval abundance increased with distance from the Bay entrance (Fig. 5) and an analysis of variance comparing catch means of all larvae produced an F ratio 0.5871/0.0255 = 23.0235, with 4 and 44 df which was signifi- cant at the 1% level. The comparatively large catches from stations 4 and 5 were composed

o S i-

Figure 5. — The mean larval fish catch per cubic meter of water sampled collected in each station during 1969.

Table 1. — Species, month, size and numbers offish larvae and juveniles collected in Humboldt Bay. Calif — Continued.

Taxon

Common name

No. of Size larvae

range (mm) OT1 BT2

No. of juveniles

OT1

BT2

Month collected

Cottidae: Artedius sp.

4-9

Leptocottim armatus

Pacific staghorn

sculpin

Cottid (4 types)

Unknowns

Agonidae:

Odon topyxis t rispi >i osa

Pigmv poacher

Stellerina as yon tenia

Pricklebreast

poacher

Cyclopteridae:

Cyclopterid (2 types)

Unknowns

Ammodytidae:

Ammodytes hexapterus

Pacific sand

lance

Blennioidei:

(2 types)

Unknowns

Atherinidae:

At he ri nops is ca lifornien s in

Jacksmelt

Bothidae:

Citharichthys stigmaeus

Speckled

sanddab

Paralichthys californicus

California

halibut

Pleuronectidae:

Parophrys vetulus

English sole

Platichthys stellatus

Starry flounder

Psettichthys melanostictus

Sand sole

Pleuronectid

Unknown

1 Oblique tow.

2 Bottom tow.

3-8

40

213

3-8

33

88

14

-

-

4-17

-

3

3-4

1

1

3-7

7

36

3-14

1

5

8-10

3

5

3

1

-

3

1

-

7

__

1

5-9

—

7

18

--

--

3-4

4

17

Feb., Oct.

an. -Apr., Sept. -Dec. an. -May, July

Dec.

une, Julv, Oct.

an., May

an. -Apr.

an. -Apr.

Apr. -June

Dec.

Mar.

Dec.

June-Aug. Jan. Jan. -Apr.

primarily of Pacific herring and bay goby. They comprised 88% of the larvae collected in station 4 and 89% in station 5. On the other hand, the two least productive stations, 2 and 3, were located near the mouth of the Bay and they differed from stations 1, 4, and 5 in that they had no eelgrass or mudflats in close proximity. In addition, the water currents were visually noted to be the great- est in stations 2 and 3.

Although station 5 had the second highest catch rate, it exhibited the lowest number of species (Fig. 6). This may be linked to the comparatively wide range in temperature and salinity found in station 5. The Pacific herring, northern anchovy, longfin smelt, an unknown smelt, bay goby, arrow goby, and the Pacific staghorn sculpin were most ubiqui- tous during the course of the study. Whereas offshore species, bothids, and plueronectids were largely confined to the stations nearest the Bay entrance, resident demersal groups (cottids and gobiids) were concentrated in Areata Bay.

3 4

SAMPLING STATIONS

Figure 6. — The number of species of fish larvae and juveniles collected in each station during 1969.

Seasonal Distribution

Two periods of abundance are evident in the seasonal distribution of the average month- ly larval fish catch per cubic meter (Fig. 7). The peak in January and February is primari- ly due to Pacific herring, and the high in April and May is a result of large bay goby catches. A slight increase in catch was noted in October because of an increase in the num- ber of arrow gobies; however, fish larvae were comparatively scarce after June. The

" *-WmmlM

JAN FIB MAI API MAT JUN JUl AUO SIP OCT NOV OIC

Figure 7. — The mean fish catch per cubic meter of water sampled each month during 1969.

.-. . . ■ ■ ■ ■ , ■ i ■ ■■ ■ — -

AUG ' SIP ' OCT ' NOV ' DEC

Figure 8. — The number of species of fish larvae and juveniles captured each month during 1969.

period from January to May yielded the high- est average number of species caught (Fig. 8). They consisted primarily of resident in- shore species, Sebastes spp., hexagrammids, cottids, and the Pacific sand lance. The longfin smelt was collected throughout the year with the largest numbers in January. Interestingly, the December catch exhibited a marked in- crease in the number of species while the catch remained low. This was the effect of an influx of larvae spawned offshore. The Northern anchovy was collected sporadically during four different times of the year.

DISCUSSION

The ichthyoplankton population of Humboldt Bay appears to follow a pattern in which the majority of species are endemic to the immedi- ate area. In this survey 32 of the 37 collected

species are commonly found in nearshore areas.

Four fish species (Cynoscion nobilis, Steno- brachius leucopsarus, Tarltonbeania crenu- laris, and Cyclothone acclinidens) were not previously known to exist in the Bay and represent new introductions to the list of Bay fauna (Gotshall and Allen, in preparation).1 The latter three species are classified as meso- pelagic fishes and exhibit diel migration in offshore waters (Pearcy and Laurs, 1966). Cyclothone acclinidens is recorded as abun- dant and is commonly found at a depth of 100 ft or more (Fitch and Lavenburg, 1968). The occurrence of these fishes in shallow in- shore areas is most likely due to fortuitous drifting of larvae into Humboldt Bay. Fast (1960) believed seasonal oceanographic con- ditions involving changes in current directions were responsible for large catches of Steno- brachius leucopsarus in Monterey Bay. Like- wise, for Humboldt Bay, onshore currents resulting from southerly winds combined with tidal movements could bring these mesopelagic larvae into the Bay. Wind direction data from near the Bay for the periods of capture of these fishes generally indicate either mixed conditions or predominate southerly winds. It has also been noted (Ahlstrom, 1959) that most fish larvae, including the three meso- pelagic species in this survey, were found in the upper part of the thermocline to ap- proximately 125 m. This would place the fish larvae in the waters most influenced by sur- face winds. A concluding factor is that all but two of the specimens representing four species were captured near the Bay entrance.

Localization in distribution was evidenced with the bothids, pleuronectids, and offshore species near the Bay entrance, and cottids and gobies in Areata Bay. Their limited dis- tribution were most likely due to being spawn- ed and surviving in large numbers only within certain areas. For many species the small numbers captured obviate a discussion of their distribution.

Winter freshwater runoff and shallow depth were responsible for the wide range in salinity and temperature in station 5. Concurrently,

1 Gotshall, D., and G. H. Allen. Annotated checklist of Humboldt Bay. Manuscript in preparation.

the number of species found at station 5 was the lowest which may reflect the limiting en- vironmental conditions. The estuarine waters at the other four stations were mixed well from surface to bottom by virtue of the large tidal prism relative to the volume of the Bay and the turbulence on both the flood and ebb tide stages.

In the pelagic larval fish surveys along the California coast, most notably the California Cooperative Fisheries Investigations, larval fish abundance is measured in numbers of individuals below 1 square meter of sea sur- face. This analysis is confined to results of oblique plankton net hauls. For surveys in estuarine areas, this method becomes more complicated because of the shallowness of the stations which often necessitates develop- ment of specialized sampling gear as in this study. In order to compare the results of the sled and the oblique tows, we chose to use larvae per cubic meter strained. This and similar values have been commonly used in studies along the east coast of the United States (Lewis and Mann, 1971; Pearcy and Richards, 1962; Richards, 1959). It should be noted, however, that numbers of fish larvae per volume of water strained are not strictly comparable values but density measurements. If the total number of larvae in an area are used for the analysis of horizontal distribu- tion, more meaningful conclusions of the rela- tive productivity of different areas can be formed.

The Pacific coast of the United States (ex- cluding Alaska) has remarkably few estu- aries. Consequently, those that do exist are focal points for population concentrations and commercial and industrial developments. The extent to which these marine environ- ments have been modified by man's activities is not fully known. Yet the rate of activity is increasing and the need to understand and evaluate the effects of these activities on the ecosystem has become important. Estuarine larval fish surveys can provide information relating to the utilization of inshore areas for spawning and nursery grounds both in space and time. By monitoring the larval fish population over long periods of time, it is also possible to determine the rate and extent of change in the abundance and species

composition of these fishes. This larval fish survey offers some basic information relating to the larval fish population in Humboldt Bay. Further research is presently needed for development of more efficient sampling methods, for gathering information on the distribution of fish larvae within the estuary and how it changes with time, and for under- standing how physical-chemical conditions affect distribution.

ACKNOWLEDGMENTS

We wish to thank C. S. Apperson for his assistance in the data acquisition, which often took place under inclement conditions. We also greatly appreciate the help provided by E. H. Ahlstrom and his staff. Dr. Ahlstrom's critical review and comments on the manu- script were especially helpful.

This study was supported by the California Cooperative Fisheries Unit, Humboldt State College, and was submitted in partial ful- fillment of the Master of Science degree re- quirement.

LITERATURE CITED

AHLSTROM, E. H.

1959. Vertical distribution of pelagic fish eggs and larvae off California and Baja California. U.S. Fish Wildl. Serv., Fish. Bull. 60:107-146.

1965. Kinds and abundance of fishes in the Cali- fornia Current region based on egg and larval surveys. Calif. Coop. Oceanic Fish. Invest. Rep. 10:31-52.

BOLIN, R. L.

1944. A review of the marine cottid fishes of Cali- fornia. Stanford Ichthy. Bull. 3:1-135. BREDER, C. M., JR., and D. E. ROSEN.

1966. Modes of reproduction in fishes. Nat. Hist. Press, Garden City, N.Y., 941 p.

BUDD, P. L.

1940. Development of the eggs and early larvae of six California fishes. Calif. Dep. Fish Game, Fish Bull. 56, 53 p. CLEMENS, W. A., and G. V. WILBY.

1961. Fishes of the Pacific coast of Canada. Fish. Res. Board Can., Bull. 68, 443 p. CLOTHIER, C. R.

1950. A key to some southern California fishes based on vertebral characters. Calif. Dep. Fish Game, Fish Bull. 79, 83 p.

EICHENBERRY, J.

1971. Seasonal and spatial distribution of mero- plankton in north Humboldt Bay. M.S. Thesis, Humboldt State College, Areata, Calif., 48 p. FAST, T. N.

1960. Some aspects of the natural history of Steno- branchiiis leticopsarns Eigenmann and Eigen- mann. Ph.D Thesis, Stanford Univ. (Libr. Congr. Card No. Mic. 60-6729) 107 p. Univ. Microfilms. Ann Arbor, Mich. (Diss. Abstr. 21:2833-2834.) FITCH, J. E„ and R. J. LAVENBERG.

1968. Deep-water teleostean fishes of California. Univ. Calif. Press, Berkely, 155 p. HART. J. L., and J. L. McHUGH.

1944. The smelts (Osmeridae) of British Columbia. Fish. Res. Board Can., Bull 64, 27 p. HICKMAN, C. P., JR.

1959. The larval development of the sand sole (Pset- tichthys melanostictus). Wash. Dep. Fish., Fish. Res.Pap. 2(2):38-47. JONES, A. C.

1962. The biology of the euryhaline fish, Leptocottus armatus armatus Girard. Univ. Calif. Publ. Zool. 67:321-368. LEWIS, R. M., and W. C. MANN.

1971. Occurrence and abundance of larval Atlantic menhaden, Brevoortia tyrannus, at two North Carolina inlets with notes on associated species. Trans. Am. Fish. Soc. 100:296-301. MISITANO, D.

1970. The early life history of English sole (Paro- phrys vetulus) in Humboldt Bay. M.S. Thesis, Humboldt State College, Areata, Calif.. 54 p. ORCUTT, H. G.

1950. The life history of the starry flounder, Plati- chthys stellatus (Pallas). Calif. Dep. Fish Game, Fish Bull. 78, 64 p. ORSI.J. J.

1965. The embryology of the English sole, Paro- phrys retains. Calif. Dept. Fish Game 54:133-155.

PEARCY, W. G.. and R. M. LAURS.

1966. Vertical migration and distribution of meso- pelagic fishes off Oregon. Deep-Sea Res. 13:153- 165.

PEARCY, W. G., and S. W. RICHARDS.

1962. Distribution and ecology of fishes of the Mystic River estuary, Connecticut. Ecology 43:248-259.

PORTER, P.

1964. Notes on fecundity, spawning and early life history of Petrale sole (Eopsetta jordani), with descriptions of flatfish larvae collected in the Pacific Ocean off Humboldt Bay, California. M.S. Thesis, Humboldt State College, Areata, Calif., 98 p.

RICHARDS, S. W.

1959. Pelagic fish eggs and larvae of Long Island Sound. In Oceanography of Long Island Sound and Guide for Preparing Figures, p. 95-124. Yale Univ., Bull. Bingham Oceanogr. Collect. 17 (artic. 1).

ir GPO 796-325

«SmSS}^SSf)l - Serial.

5 WHSE 01843

Predation by sculpins on fall chinook salmon, Oncorhynchus tshawytscha, fry of hatchery or- igin. By Benjamin G. Patten. February 1971, iii + 14 pp., 6 figs., 9 tables.

Number and lengths, by season, of fishes caught with an otter trawl near Woods Hole, Massa- chusetts, September 1961 to December 1962. By F. E. Lux and F. E. Nichy. February 1971, iii + 15 pp., 3 figs., 19 tables.

Apparent abundance, distribution, and migra- tions of albacore, Thunnus alalunga, on the North Pacific longline grounds. By Brian J. Rothschild and Marian Y. Y. Yong. September 1970, v + 37 pp., 19 figs., 5 tables.

Influence of mechanical processing on the quality and yield of bay scallop meats. By N. B. Webb and F. B. Thomas. April 1971, iii + 11 pp., 9 figs., 3 tables.

Distribution of salmon and related oceanographic features in the North Pacific Ocean, spring 1968. By Robert R. French, Richard G. Bakkala, Ma- sanao Osako, and Jun Ito. March 1971, iii + 22 pp., 19 figs., 3 tables.

Commercial fishery and biology of the fresh- water shrimp, Macrobrachium, in the Lower St. Paul River, Liberia, 1952-53. By George C. Mil- ler. February 1971, iii + 13 pp., 8 figs., 7 tables.

Calico scallops of the Southeastern United States, 1959-69. By Robert Cummins, Jr. June 1971, iii + 22 pp., 23 figs., 3 tables.

Fur Seal Investigations, 1969. By NMFS, Ma- rine Mammal Biological Laboratory. August 1971, 82 pp., 20 figs., 44 tables, 23 appendix A tables, 10 appendix B tables.

Analysis of the operations of seven Hawaiian skipjack tuna fishing vessels, June-August 1967. By Richard N. Uchida and Ray F. Sumida. March 1971, v + 25 pp., 14 figs., 21 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - 35 cents.

Blue crab meat. I. Preservation by freezing. July 1971, iii + 13 pp., 5 figs., 2 tables. II. Effect of chemical treatments on acceptability. By Jurgen H. Strasser, Jean S. Lennon, and Fred- erick J. King. July 1971, iii + 12 pp., 1 fig., 9 tables.

Occurrence of thiaminase in some common aquat- ic animals of the United States and Canada. By R. A. Greig and R. H. Gnaedinger. July 1971, iii + 7 pp., 2 tables.

An annotated bibliography of attempts to rear the larvae of marine fishes in the laboratory. By Robert C. May. August 1971, iii + 24 pp., 1 ap- pendix I table, 1 appendix II table. For sale by the Superintendent of Documents, U.S. Govern- ment Printing Office, Washington, D.C. 20402 - 35 cents.

Blueing of processed crab meat. II. Identification of some factors involved in the blue discoloration of canned crab meat Callinectes sapidus. Bv Melvin E. Waters. May 1971, iii + 7 pp., 1 fig!, 3 tables.

634. Age composition, weight, length, and sex of her- ring, Clupea pallasii, used for reduction in Alas- ka, 1929-66. By Gerald M. Reid. July 1971, iii + 25 pp., 4 figs., 18 tables.

635. A bibliography of the blackfin tuna, Thunnus atlanticus (Lesson). By Grant L. Beardsley and David C. Simmons. August 1971, 10 pp. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - 25 cents.

636. Oil pollution on Wake Island from the tanker R. C. Stoner. By Reginald M. Gooding. May 1971, iii + 12 pp., 8 figs., 2 tables. For sale by the Superintendent of Documents, U.S. Govern- ment Printing Office, Washington, D.C. 20402 - Price 25 cents.

637. Occurrence of larval, juvenile, and mature crabs in the vicinity of Beaufort Inlet, North Carolina. By Donnie L. Dudley and Mayo H. Judy. August 1971, iii + 10 pp., 1 fig., 5 tables. For sale by the Superintendent of Documents, U.S. Govern- ment Printing Office, Washington, D.C. 20402 - Price 25 cents.

638. Length-weight relations of haddock from com- mercial landings in New England, 1931-55. By Bradford E. Brown and Richard C. Hennemutti. August 1971, v + 13 pp., 16 fig., 6 tables, 10 appendix A tables. For sale by the Superintend- ent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 25 cents.

639. A hydrographic survey of the Galveston Bay system, Texas 1963-66. By E. J. Pullen, W. L. Trent, and G. B. Adams. October 1971, v + 13 pp., 15 figs., 12 tables. For sale by the Super- intendent of Documents, U.S. Government Print- ing Office, Washington, D.C. 20402 - Price 30 cents.

640. Annotated bibliography on the fishing industry and biology of the blue crab, Callinectes sapidus. By Marlin E. Tagatz and Ann Bowman Hall. August 1971, 94 pp. For sale by the Superinten- dent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price $1.00.

641. Use of threadfin shad, Dorosoma petenense, as live bait during experimental pole-and-line fish- ing for skipjack tuna, Katsuwonus pelamis, in Hawaii. By Robert T. B. Iversen. August 1971, iii + 10 pp., 3 figs., 7 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 25 cents.

642. Atlantic menhaden Brevoortia tyrannus resource and fishery — analysis of decline. By Kenneth A. Henry. August 1971, v + 32 pp., 40 figs., 5 appendix figs., 3 tables, 2 appendix tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 45 cents.

646. Dissolved nitrogen concentrations in the Colum- bia and Snake Rivers in 1970 and their effect on chinook salmon and steelhead trout. By Weslev J. Ebel. August 1971, iii + 7 pp., 2 figs., 6 tables. For sale by the Superintendent of Doc- uments, U.S. Government Printing Office, Wash- ington, D.C. 20402 - Price 20 cents.

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NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION

NATIONAL MARINE FISHERIES SERVICE

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MARINE BIOLOGICAL LABORA LIBRARY - PERIODICALS - WOODS HOLE, KA 02543

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