VIRGINIA JOURNAL OF SCIENCE

OFFICIAL PUBLICATION OF THE VIRGINIA ACADEMY OF SCIENCE

Vol. 62 No. 3 Fall 2011

TABLE OF CONTENTS

ARTICLES PAGE

Breeding Biology of Oryzomys Palustris, the Marsh Rice Rat, in

Eastern Virginia. Robert K. Rose and Erin A. Dreelin. 113

Abstracts missing from Volume 62 Number 1 & 2 123

Academy Minutes 127

The Horsley Award paper for 2011 135

Virginia Journal of Science
Volume 62, Number 3
Fall 2011

Breeding Biology of Oryzomys Palustris, the Marsh Rice

Rat, in Eastern Virginia

Robert K. Rose 1 and Erin A. Dreelin 2 , Department of Biological
Sciences, Old Dominion University, Norfolk, Virginia 23529-0266

ABSTRACT

The objectives of our study were to determine the age of maturity, Utter size,
and the timing ofthe breeding season of marsh rice rats (Oryzomys palustris)
of coastal Virginia. From May 1995 to May 1996, monthly samples of rice
rats were Uve-trapped in two coastal tidal marshes of eastern Virginia, and
then necropsied. Sexual maturity was attained at 30-40 g for both sexes.
Mean Utter size of 4.63 (n = 16) did not differ among months or in mass or
parity class es. Data fromtwo other studies conducted in the same county, one
of them contemporaneous, also were examined. Based on necropsy, rice rats
bred from March to October; breeding did not occur in Dcccmber-Fcbruaiy.

By contrast, rice rats observed during monthly trapping on nearby Uve-trap
grids were judged, using external indicators, to be breeding year-round except
January. Compared to internal examinations, external indicators of
reproductive condition were not reUable for either sex in predicting breeding
status in the marsh rice rat.

INTRODUCTION

Oryzomys palustris (Harlan), the marsh rice rat, has the northernmost range in the
genus Oryzomys, extending from southern Texas and Florida as far north as southern
New Jersey. Apart from O. couesi Alston, found in two counties in southern Texas,
other Oryzomys species are distributed from Mexico to South America (HaU 1981).
(NOTE: A recent paper [Hanson et al. 2010], which explores molecular divergence in
Oryzomys, suggests the possibility that Oryzomys in parts of Mississippi and Louisiana
should be assigned to O. texensis. But even afterapossible revision ofthe taxonomy,
O. palustris lives in the most seasonal environments for this tropical genus.)

Studies of the reproductive biology of the marsh rice rat have not provided a
consensus on the timing and duration ofthe breeding season, hi Mississippi, using
assessments from live-trapped animals only, Wolfe (1985) observed breeding year
round with the major breeding period from late spring to late autumn. By contrast, in
Louisiana, breeding was not observed during two of three winters in which rice rats
were trapped (Negus et al. 1961). Edmonds and Stetson (1993) report the breeding
season in Delaware usually extends from March to September, but can last into late
autumn when environmental conditions are favorable. Svihla (1931) and Worth (1950)
report February-October breeding seasons in eastern Texas and Florida, respectively.

! brose@odu.edu

2 Current address: Center for Water Sciences and Department ofFisheries and Wildlife, Michigan
State University, 13 Natural Resources Building, East Lansing, Michigan 48824, dreelin@msu.edu.

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VIRGINIA JOURNAL OF SCIENCE

Laboratory studies provide a similar picture of occasional year-round breeding, with
Conaway (1954) reporting year-round breeding for captive rice rats from Tennessee.

Whereas small mammals in the tropics often breed year round, in temperate
latitudes they commonly cease or reduce breeding in the winter. To compensate fora
shorter breeding season, they frequently increase reproduction with larger or more
frequent litters or by maturing more quickly. We sought to learn how O. palustris,
living far from its tropical origins, has adjusted its breeding season near the northern
limits of its distribution. We also were interested to leam if litter sizes are similar to
southern populations and whether sexual maturity is reached at 30-40 g, as in other
regional populations (Conaway 1954, Negus et al. 1961) or if maturity is reached
earlier to compensate for a shorterbreeding season. The objectives of our study were
to determine the age of maturity, litter size, and the timing of the breeding season of
marsh rice rats of coastal Virginia. We examined whether rice rats mature at 30-40g
and tested the null hypotheses that litter size does not vaiy throughout the breeding
season and that O. palustris populations in coastal Virginia have equal breeding
intensity for each bimonthly period throughout the year.

MATERIALS AND METHODS

We trapped rice rats monthly fromMay 1995 through May 1996 fromtidalmarshes
at two sites near Oyster and Townsend in Northampton County on the Eastern Shore
of Virginia. Marshes in this region are dominated by Spartinaal tern (flora Lois el, salt
marsh grass, S. patens Muhl., salt meadow hay, Juncus roemerianus Scheele, black
needlerush, and Baccharis halimifolia L., saltbush. Traplines were placed at the wrack
line, i.e., the transition from the Spartina spp. and needlerush to saltbush, so all
vegetation types were trapped.

We set traplines consisting of 50-60 Fitch live traps (Rose 1994) at 2-3 mintervals
in transects on the wrack line just above mean high waterat each site. We baited traps
with birdseed in the evening and checked them in the early morning. Potentially
mature rice rats ( > 30 g) were euthanized in the field with chloroform and stored in a
-20 C freezer until necropsy; smaller rice rats and other species were released. Our
methods followed the 1987 guidelines of the American Society of Mammalogists for
the use of mammals in research (eld hoc Committee 1987).

Necropsy methods and variables measured followed those of Keller and Krebs
(1970). We recorded mass (g), total length (mm), and lengths (mm) of the tail, ear, and
hind foot and assigned rice rats to sub-adult (31-50 g) and adult (> 51 g) age classes
following the criteria of Wolfe (1985). We also recorded a fat index for each rice rat
with 1 designating no fat, 2 for gonadal fat only, 3 with the addition of inguinal or
scapular fat, 4 with the addition of mesenteric fat, and 5 for obese rats. Additional
information recorded for females included perforate or imperforate vagina, open or
closed pubic symphysis, uterine mass (mg), numbers of embryos, resorbing embryos,
and placentalscars,and numbers ofcorpora lutea and corpora albieantia. We classified
females as nulliparous (having no reproductive experience) ifthe pubic symphysis was
closed and there was no evidence of placental scars or ovarian corpora. Primiparous
females had pubic bones separated and embryos or placental scars and corpora of
similar size and appearance. Multiparous females had separated pubic bones combined
with both embryos and placental scars (or numerous scars of two color classes) and
coq^ora that differed in appearance. For males, we recorded the position of the testes

BREEDING BIOLOGY OF Otyzomys Palustris

115

(abdominal or scrotal), masses of testes and seminal vesicles (mg), and looped or
convoluted epididymis. If the cauda epididymides are convoluted, then sperm are
present and the male is fertile (Jameson 1950). We defined winter as Dec-Feb, summer
as Jun-Aug, and spring and autumn as the intervening months.

We also used data from two other studies of nee rats from the same county in the
analysis. Rice rats fromFisherman’s Island, 7 kmsouth of our field sites, were trapped
and necropsied in January and February 1982; these are the only necropsy results from
January and February. Additional information on breeding condition was gleaned from
rice rats captured during a contemporaneous population study (Bloch and Rose 2005),
which used capture-mark-release (CMR) methods on two grids located within 2 kmof
our removal transects and provided information during the same months that we
collected our rice rats for necropsy. Bloch and Rose (2005) provides external
information on reproduction: males with scrotal testes were considered to be breeding
and for females, vaginal patency, nipple size, and pregnancy were recorded, whereas
necropsied animals yielded both internal and external reproductive information.

The hypothesis that rice rats breed throughout theyearwastestedusingChi-square
analysis. Differences in litter size between age classes were analyzed using ANOVA.

We examined differences in litter size by parity with ANOVA after the data had
been square-root transformed. A Kruskal-Wallis test was used to analyze differences
in litter sizes by month because the assumptions of normality for ANOVA tests were
not met even after data transformations. Pearson’s correlations were used to examine
the relationship between fat indexand breeding condition. Finally, logistic regression
was conducted to determine how effectively external indicators can predict breeding
condition.

RESULTS

We trapped 85 males for necropsy during May 1995-May 1996. However, due to
a sharp mid-winter decline in population density (also observed on Bloch’s CMR
grids), no males were trapped duiing January or February. We necropsied 44 females,
but 0 were captured during May 1995 or the next January, February, or March. Rice
rats reached sexual maturity close to the 30-40 g expectation. The smallest pregnant
female was 34 g and the smallest male with convoluted cauda epididymides was 43 g.

Sixteen pregnant females were captured during the study: in April, July, August,
September, and October (Table 1). When these differences in litter size among months,
parity, and age classes were examined, litter sizes did not differ among months (H =
0.09, NS). After data for litter size by month were square-root transformed to meet the
assumptions of ANOVA, litter size did not vaiy between primiparous (x =4.89) and
multiparous (x = 4.00) females (F = 1.61, NS) or between subadults (x = 3.83) and
adults (x = 5.10;F = 3.86, NS).

For the analysis of breeding season, allnecropsied rice rats (n= 170), including the
41 ffomJan-Feb 1982 fromFisherman’s Island, were combined into bimonthly periods
to conpensate for small sample sizes. Males were in breeding condition from March
to November (Figure 1), but both testes and seminal vesicles showed substantial
regression with the approach of winter. The mean mass of paired testes, expressed as

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VIRGINIA JOURNAL OF SCIENCE

TABLE 1. Mean litter size for Oryzomys palustris based on embryo counts during the year.

Month

Mean

n

April 6.001

6.00

1

July4.502

4.50

2

August4.673

4.67

3

September4.889

4.88

9

October

1.00

1

Totals

4.63

16

4 9 10

6 2

100 %

90%

80%

70%

60%

50%

40%

30%

20%

10 %

0 %

May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

Date(1995-1996)

FIGURE 1. The percent of male rice rats from eastern Virginia in breeding condition from May 1995
through May 1996. Males were considered to be breeding if the cauda epididymides were convoluted.
Numbers above bars indicate sample sizes.

mg/10 g of body mass, was greater in spring and summer (50.9-113.7) than during
November (14.1) and December (7.3). The mean mass of seminal vesicles (also in
mg/10 g body mass) also was greater in spring and summer (36.7-139.6) than in
November (13.9 mg) and December (2.5). The mean testes masses, expressed as
mg/10 g body mass, were 11.73 ± 8.2 for January 1982 and 51.17 ± 4.6 for February
1982, compared to 103.4 ± 5.5 in July and 113.7 ± 3.4 in August, the period of peak
breeding. Mean body masses of male rice rats trapped in January 1982 (x =57.8± 2.7
g; n = 15) and in February 1982 (x = 60.8 ± 3.1 g; n = 11) indicated that winter males
were large adults. The mean mass of females for January 1982 was 38.5 ± 3.2 g (n =
4) and for February 1982 was 49.6 ± 2.0 g (n = 11).

Rice rats in breeding condition were found from March-April to November-
December (Figure 2), with males having a longer breeding season on each end than

BREEDING BIOLOGY OF Oryzomys Palustris

117

120

C

.2

’■J3

XS

C

o

u

GO

c

xi

<u

Qi

v_

CO

C

C

<u

u

<v

Cl

Bimonthly Period

FIGURE 2. The percent of breeding rice rats from eastern Virginia for bi-monthly periods, when breeding
condition is defined as descended testes in males and pregnant, lactating, or recently littered for females.
Results for both sexes combined and including animals collected from Fisherman’s Island in Januaiy and
February 1982; no rice rats were caught in Januaiy or February 1996.

100% n

I

90% j

|

80% -J

70% -j

60% -f

50% •{

40% j
30% -j
20 % j
10 %

1 0

0 % 4 ..

May

12 6

1

Jun Jui Aug Sep

5

Oct Nov Dec Jan

Date (1995-1996)

0 1 1
Feb Mar Apr May

FIGURE 3. The percent of female rice rats fom eastern Virginia in breeding condition ifoni May 1995
through May 1996. Females were considered to be in breeding condition if they were pregnant, lactating,
or recently had litters.

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VIRGINIA JOURNAL OF SCIENCE

TABLE 2. Percent correct of external indicators in predicting breeding condition in marsh rice rats from
eastern Virginia, as determined by logistic regression. Regressions using nipple size and nipple size + mass
were unsuccessfrtl due to small sample sizes.

Model

Percent correct

G

df

r

SE

P

Scrotal testes

73.2

77.01

1

0.98

0.7979

0.0001

T estes + mass

92.6

67.62

2

0.86

0.0268

0.0066

Perforate vagina

61.5

54.05

1

0.92

0.7585

0.0001

Vagina + nipple size

68.5

42.32

2

0.83

1.1853

0.1294

Vagina + mass

92.9

34.14

2

0.86

0.0573

0.0039

females. The null hypothesis that rice rats breed at uniformrates throughout the year
was rejected (X 2 = 86.9b df = 5, p < 0.001). Breeding females (pregnant, lactating, or
recently Uttered) were recorded during June-October and the next April (Figure 3).

Fat index and breeding condition were not correlated for either males (r = 0.1188,
NS) or females (r = 0.0320, NS). Fat index was negatively correlated with percent
breeding in the month for males (r = -0.2177, p < 0.05) but not for females (r = -0.1063,
NS). Males trapped in January-Febmary 1982 (midwinter) had higher fat indices than
those trapped in July-August 1995 (midsummer) (t = 3,69, df = 14, p < 0.05).
However, fat indices in a similar comparison of females did not differ significantly.
Rice rats with high fat indices (large fat stores ) were trapped during winter, whereas
those trapped in spring had lower fat indices.

Logistic regression was used to analyze external predictors of breeding condition
(Table 2). For males, the best predictor (highest r-value) was descended testes (r =
4.5462, df = 1, p <0.001). When breeding condition is defined as pregnancy, lactation,
or recently Uttered, the best predictor for females was perforate vagina (r = 3.1781,
df= 1, p <0.001). For both sexes, mass was also a useful predictor variable.

DISCUSSION

Based on necropsied specimens coUected at monthly intervals throughout the year,
female rice rats bred from April to October, and males were fertile a few weeks eariier
and later than females. However, neither sex was fertile during the winter months of
December, 1995 and January and February, 1982, although males rapidly regained
fertifrty in Februaiy. Litter sizes and masses at maturity were similar to those of other
southern populations of rice rats.

Litter size did not differ among months, between age classes, or with parity.
Placental scar counts were not used to assess Utter size because to be accurate,the time
of parturition should be known (Martin et al. 1976). Also, previous studies of rice rats
have used only embryo counts (Negus et al. 1961, Edmonds and Stetson 1993) or
counts of young at parturition in the laboratory (Conaway 1954). The latter method
may underestimate Utter size because recently parturient females may eat their stifrbom
orotheryoung without those losses being detected. AUstudies ofUttersize have smafr
sample sizes of pregnant females: Conaway (1954, n = 5), Exlmonds and Stetson (1993:

BREEDING BIOLOGY OF Oiyzomys Palustris 119

n =20), and we examined 16 pregnant females. Although these sample sizes are small,
there is little variation among populations.

Many small mammals show a trend of increased litter size in northern populations
(Sadleir 1969). The mean litter size of 4.63 young for our study was comparable to that
of 4.8 young reported for the 3-year study of Negus et al. (1961) in Louisiana but was
much smaller than the mean of 6.7 young of the Delaware populations (Edmonds and
Stetson 1993). The larger litter size of Delaware rice rats may be an adaptation to
increase reproductive output in response to a shorterreproductiveseason; Delaware is
near or at the northern limit ofthe distribution of Oiyzomys palustris. Such responses
by geographic populations are illustrated by Sigmodon hispidus Say and Ord (hispid
cotton rat), for which litter size ranges from 2.5 in Is la del Toro, Mexico, 4.8 in
Houston,Texas, 6.0 in Stillwater, Oklahoma, to 9.0 in Lawrence, Kansas (Cameronand
McClure 1988). These authors conclude that variation in litter size in geographic
populations of S', hispidus is attributable to greater seasonality of resources and to
abiotic factors in populations with larger litter sizes. The increased litter size of
northern populations probably is ameans to increase reproductive output in a shortened
breeding season (Sadleir 1969). Given the absence of breeding during the winter, we
would have expected larger litter sizes in the Virginia population.

External and internal indicators showed some agreement in the age at which rice
rats reached sexual maturity. The smallest necropsied pregnant female, 34 g, was only
slightly smaller than the 39-g female judged to be pregnant on the CMR grids (Bloch
and Rose 2005). However, the mass of males at maturity differed between the studies
because the smallest necropsied males with convoluted epididymides were 43 g
whereas one male under 20 g had scrotal testes on the CMR grids. Although several
juvenile males on the CMR grids had descended testes, most did not. Overall, there
was modest agreement in the external and internal indicators of reproduction that rice
rats mature at 30-40 g. However, based on external features, males appear to have
reached maturity before females. By contrast, the common pattern seen in studies of
other genera of small mammals is for males to mature days or weeks after females
(Sadleir 1969).

In ournecropsy study, breeding males were observed lfomMarch to November, but
by November the percent in breeding condition was declining and none was seen in
December. Therefore, the transition from breeding to non-breeding status was
documented before the population crash (no rice rats were trapped in January or
February 1996). The males trapped on Fisherman’s Island in January-February 1982
were not in breeding condition, which further supports that Virginia rice rats do not
breed in winter.

The mass of testes declined during late autumn and in winter, which corresponded
to the cessation of breeding. The gonads of small mammals regress to minimal levels
during periods of non-breeding (e.g., Sadleir 1969). For example, the testes of adult
hispid cotton rats from southeastern Virginia regress during late autumn to about 1/25
(2000 vs 80 mg) that of values during the breeding season (Rose and Mitchell 1990).
Although the male rice rats trapped in Jan-Feb 1982 were adults based on body mass,
the mean testes mass (expressed as mg/10 g body mass) were 10-49% of mean testes
mass ofmales from July and August. Thus, with body masses near 60 g, these winter
males were full adults with highly regressed testes.

Pregnant females were recorded in spring, summer, and autumn but none in

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VIRGINIA JOURNAL OF SCIENCE

November or December 1996. If defined by pregnant females alone, the breeding
season is April-October. The females trapped in January and February 1982, with body
sizes sufficiently large to reproduce, were not breeding either, contributing additional
support that rice rats do not breed in winter in eastern Virginia.

An inverse relationship between breeding season and fat index was expected;
however, only males showed a significant correlation between fat index and percent
breeding in the month. Males with greater fat stores were trapped in winter; allhad fat
deposits around the testes, which is the site of the first-laid fat for males. Although
females showed the same pattern of greater fat stores in winter,the correlation was not
significant. Lacking the brown adipose tissue that many temperate small mammals use
during winterto make heat by non-shivering thermogenesis, the storage offat in winter
may represent an adaptation in rice rats for winter conditions. Laboratory mice, Mus
musculus , which also lack brown tat, when kept in cool conditions (11 C) die within
hours of missing one feeding period because they have a high metabolism and small
energy stores (Bronson 1989). Bronson and Peirigo (1987) conclude that due to their
energy-related constraints, smallmammals usually allocate energy to fat storage rather
than reproduction when thermoregulatory cos ts are high, as in winter at most locations
in the southeastern US. If so, then rice rats may have sufficient energy to breed in
Louisiana during mild winters but most winters in Virginia or Delaware are
substantially longer and colder, making winter breeding unlikely or rare there.

In orderto coup a re estimates of reproduction with contemporaneous populations
from nearby CMR grids (Bloch and Rose 2005), we excluded rice rats < 30 g to
conform to necropsied animals. Position of testes and vaginal patency were used to
assess the breeding condition ofrice rats trapped on the CMRgrids. Males in breeding
condition were recorded throughout the year but the percent of males in breeding
condition was low during the months of winter (25-50%) and highest in spring (67-
100%) and summer (91-100%). Although perforate females were found throughout the
year, the percent was highest in spring and summer and declined in winter (Bloch and
Rose 2005) and the percent of females judged to be pregnant (0% in winter) was
highest in spring (> 50%) and summer (> 42%) and declined in autumn months (<
46%).

Thus, in contrast to the results ofnecropsied specimens, marsh rice rats on the CMR
grids were judged to be in breeding condition throughout the year (Bloch and Rose
2005). The percentage of mature rice rats in breeding condition based on external
examination did decline in autumn, but a substantial number remained in breeding
condition in December (14-68%), January (19-25%), and February (8-100%). Wolfe
(1985) also concluded marsh rice rats bred year round in Miss issippi, but he, like Bloch
and Rose (2005), evaluated only CMR animals. However, none of the necropsied rice
rats were in breeding condition in winter based on the internal indicators evaluated in
our study.

We conclude that external indicators are unreliable in predicting the real breeding
status of marsh rice rats. The results of our necropsy study and those of the
contemporaneous CMR study differed due to the subjectivity and relative inaccuracy
of external indicators. For example, six of 16 necropsied pregnant females were
classified as non-breeders based on external indicators; they were not perforate, had
small nipples, closed pubic symphyses, and were not visibly or heavily pregnant.
McCravy and Rose (1992) also found external indicators to be less accurate for females

BREEDING BIOLOGY OF Oryzomys Palustris

121

than for males. The inaccuracy of external indicators may be the reason that rice rats
studied on the CMR grids (Wolfe 1985, Bloch and Rose 2005) show signs of breeding
throughout the year whereas breeding during the wintermonths was not observed for
the rice rats examined by necropsy. Thus, the breeding season of the rice rat in
Virginia, based on the time for the first to last conception, was from March to October.
Large overwintering males regain fertility in February with rapid testicular
recrudescence and a smaller fraction of males remains fertile for part of November.
Although no necropsied male was judged to be fertile in December or January,
testicular regression was less pronounced than that seen in male hispid cotton rats of
the region, perhaps enabling a rapid return to fertility should benign winter conditions
persist, as they sometimes do in coastal Virginia.

ACKNOWLEDGMENTS

We thank Old Dominion University and The Nature Conservancy (TNC) for grant
support and also thank TNC for permission to conduct our study on their property.
Thanks to C. Bloch, A. Emerick, M. Watson, and S. Wright for help with field and lab
work, and to two anonymous reviewers for useful comments to improve accuracy and
clarity.

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southern Indiana, 1965-1967. Ecological Monographs 40:263-294.

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Rose, R. K., and M. H. Mitchell. 1990. Reproduction of the hispid cotton rat
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2011 MEETING MISSING ABSTRACTS

123

DEVELOPMENT OF A QUANTUM DOT SIMULATOR (QDSIM) FOR
RESEARCHING SEMICONDUCTOR NANO-CRYSTALLINE PHOTO
DETECTORS AND LASERS. Anthony A. Teate, Dept, of Integrated Science and
Technology, James Madison University, 701 Carrier Drive, Harrisonburg, VA 22807.
Semiconductor Quantum Dot (QD) nanostructures with dimensions on the order of the
thermal DeBroglie wavelength of electrons provide three-dimensional (3-D) quantum
confinement of carriers. These nano-crystallites have lead to a recent class of laser
sources and photo detectors which are an alternative to the conventional bulk and
quantum well devices. An important tool for making progress in the development of
these laser sources and detectors is the modeling and simulation of the devices to be
realized. This requires the use of good methods that are able to incorporate various
physical phenomena present in real devices. In this paper we discuss the details of the
development and implementation of a computer software program that provides an
interactive environment for studying and researching quantum dot devices. This
quantum dot simulator (QDSim) allows one to analyze dynamic characteristics such as
relaxation oscillations, modulation and turn-on delay as the injection current increases
as well as other characteristics of areal quantum dot laser source. The simulator, which
is based on modeling and numerically solving rate equations for InGaAs/GaAs and
InAs/InP self-assembled quantum-dot systems using the fourth-order Runge-Kutta
algorithm, also permits researching time-resolved photoluminescence and
electroluminescence results in quantum dot photo detectors. The computer program and
physics presented here are intended as aids for teaching or conducting basic research
in the field of quantum confinement optoelectronics.

ANTIOXIDANT CONTENT OF SELECTED WINES FROM VIRGINIA
VINEYARDS. Ivy A. Walker, Elise L. Stephenson & Michael H. Renfroe , Dept, of
Biol., James Madison Univ., Harrisonburg VA 22 801. Moderate wine consumption has
been linked to reduced incidence of coronary heart disease, atherosclerosis, thrombosis,
myocardial infarction, and slightly increased longevity. These effects have been
attributed to the presence of antioxidant molecules including phenolics, flavonoids, and
stilbenes, such as resveratrol, in wines. Wines were sampled from six Virginia
vineyards extending If om Frederick County in the north to Patrick County in the south.
The antioxidant activity was measured by using the ABTS/FEOVHRP decoloration
method. Trolox, a well-characterized and stable antioxidant, was used as a comparative
standard for wine antioxidants. The highest antioxidant contents were found to be in
the red wines with a range of means from 15.38 - 7.42 pmol TE (Trolox equivalents)
/ml. Rose wines ranged fiom a mean of 4.89 - 3.40 prnol TE/ml. White wines ranged
from a mean of2.64 - 1.62 pmol TE/ml. Many antioxidants such as anthocyanins and
resveratrol are particularly concentrated in red and purple grape skins. Red wines
which include the skins during processing have the greatest antioxidant concentrations.
White wines which are made from green grapes or grapes with the skins removed
contain the least antioxidants.

IN SEARCH OF JACKSON BRIAR {SMILAXSMALLII MORONG) IN VIRGINIA.
Robert A. S. Wright, EEE Consulting, Inc., 201 Church St. SE, Blacksburg, VA.
Jackson Briar has for many years been accepted as a member of the Virginia Flora. All

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sources which documented its inclusion into the Virginia Flora were investigated,
requiring (1) a literature review which included reaching into the hallowed antiquity of
Colonial Period descriptive treatments and specimens for reportedly synonymous taxa;
(2) a search of all regional herbaria to locate the extant vouchers from VA, and; (3) a
synthesis of the collected data. The results are: (1) the taxon is reported (as S.
lanceolata L.) from VA in literature as far back as 1861, but S. smallii * S. lanceolata
= S. laurifoliaL. per Taxon Vol. 59 (2010); (2) a long-standing misidentitication of the
voucher that “documented'’ the taxon in Virginia Beach, VA (from a native habitat) has
confused the nativity of the taxon for VA; (3) unrealized “ornamental-planted” habitat
at the State Arboretum in Clarke County, VA is (partly) the erroneous basis for
inclusion of S. smallii in the recent FNA treatment of Smilax ; (4) the taxon’s long-term
valid acceptance as a member of the Virginia Flora has no basis, and (5) the ultimate
potential habitat where it could be extant in VA is estimated. The final analysis
determined that Smilax smallii “could have” historically occurred in VA as reported in
literature, but not as represented by a verified extant voucher specimen or a validly
corroborated report. Flowever, Smilax smallii could possibly occur along the southern
tier of VA. Until such time as it can be found in VA, Jackson Briar should be
considered as erroneously attributed to VA on the basis of misidentification of the
voucher [= Smilax waiteri Pursh].

A PRELIMINARY STUDY OF THE POLLINATION BIOLOGY OF AN ENDEMIC
GALAPAGOS VARRONIA (CORDIACEAE). Julia K. Stutzman & Conley K.
McMullen , Dept, of Biol., James Madison University, Harrisonburg VA 22807.
Pollination experiments, visitor observations, nectar sampling, and pollen-ovule ratio,
and pollen size were components of this investigation to determine the pollination
biology of VaiTonia scouleri (Hook, f.) Andersson (Cordiaceae), a distylous Galapagos
endemic. Flowers involved in pollination experiments produced fruit via open
pollination, “legitimate” cross-pollination (pin x thrum), diurnal pollination, and
nocturnal pollination. A significant difference in fruit set was found between flowers
that were open pollinated and “legitimately” cross-pollinated (pin x thrum), and those
that were self-pollinated. Nocturnal and diurnal fruit set did not differ significantly.
Nocturnal visitors included ants, hawk moths, and non-sphingid moths; the main
diurnal visitor was the endemic carpenter bee ( Xylocopa darwini). Flies were also
common diurnal visitors. Insufficient nectar was available for measurement. Based
on these preliminary studies, we suggest that Varronia scouleri possesses a strict
xenogamous breeding strategy (distyly), which is rare in the Galapagos Islands.

THE FLOM OF VIRGINIA PROJECT: A2010-2011 UPDATE. MarionB. Lobstein ,
Dept, of Biology, Northern Virginia C.C., Manassas, VA 22205. Virginia, for its
landmass, has the most diversity of vascular plant species of any state in the United
States. It had the first flora, the Flora Virginica in 1739, yet does not have a modern
flora. The Virginia Academy of Science for over eighty years has supported efforts to
produce a modem Flora of Virginia. In 2001 the Foundation of the Flora of Virginia,
Inc, was formed in 2001 and in May 2002 received 501(c) 3 status. Work on the
content of the Flora of Virginia including the nearly 300 of the core illustrations have
been commissioned, completed, and funded by VAS funds. Grants from the Virginia
Environmental Endowment, Southern Appalachian Botanical Society, Carrier

2011 MEETING MISSING ABSTRACTS

125

Arboretum and Botanical Gardens at JMU have been obtained for the Project during
this past year. The Academy, including the Fellows, continues to provide essential
support including financial for this Project. Other progress includes completion of
treatments of the dichotomous keys to the vascular plant families as well as the species
and genus descriptions. A contact has been signed with BRIT (Botanical Research
Institute of Texas. The projected publication date is October 2012.

FLOWER MORPHOLOGY POLLINATION SUCCESS AND REPRODUCTIVE
SUCCESS IN PASSIFLORA INCARNATA. JieRen, Laura F. Galloway & Can Dai,
Department of Biology, University of Virginia, Charlottesville VA 22904. Floral
morphology affects pollination success and reproductive success in animal-pollinated
plants. Floral traits such as flower size and anther length can increase pollination
success by affecting pollinator attraction and pollen dispersal efficiency. Similar to
among-flower variation, within-flower variation such as different levels of anther
exsertionhas also been shown to influence pollination success. However, within-flower
variation in female traits, especially style position, has received less attention. To test
the relationship between flower morphology, pollination success and reproductive
success, we studied floral traits, especially style deflexion, in Passiflorci incarnata. Our
results show that lower style deflexion increases both cross-pollination and self-
pollination. At the flower level, lower style deflexion is typically less variable and leads
to a larger quantity of pollen deposition and seed production. Higher and more variable
levels of style deflexion lead to greater variation in pollination and heavier seed weight.
In addition, a higher level of style deflexion causes an increased proportion of effective
pollination by reducing of self-pollination. These results suggest that style deflexion
is genetically controlled to promote pollination success and reproductive success as
well as reducing self-pollination.

VASCULAR FLORA OF BANSHEE REEKS NATURE PRESERVE, LOUDOUN
COUNTY, VIRGINIA, USA. Lisa D. Williams, Department of Biology, Northern
Virginia Community College, Annandale, Virginia 22003. Banshee Reeks Nature
Preserve located in the southeastern Goose Creek watershed in the Triassic basin of
Loudoun County, Virginia covers 293 hectares and was surveyed for its floristic
composition once to twice weekly during the growing seasons of 2002 and 2003.
Vascular plants from 90 families, with 211 taxa at the genus level and 281 at the
species level, were found and identified. Nineteen species are new records for
Loudoun County. Two species -Erigenia bulbosa (Michx.) Nutt, (harbinger-of-spring)
and Fraxinus nigra Marsh, (black ash) - are on the state’s watch-list. Data gathered
are currently being used as baseline information for land use decisions regarding this
natural resource area. (Funding provided by Washington Biologists’ Field Club and
the Southern Appalachian Botanical Society. Support provided by George Mason
University.)

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ACADEMY MINUTES

127

Minutes of the Virginia Academy of Science
Council Meeting Novemberl3, 2010
J. Sargeant Reynolds CC
Rm 131 Burnett Hall

The meeting was called to order at 11 am

The members present are Arun Verma, Deborah O’Dell, Darcy Mays,
Werner Wieland, Susan Booth, Hillary Stewart, Michael Renfroe, Art
Conway, Carolyn Conway, Ralph Eckerlin, David Crosby, Stephen
Gallik, Rodney Dyer, Art Burke, Tom Haas, George Grant, Elsa Falls,
Ellis Bell, Richard Groover, Jim O’Brien, Marion Lobstein

President Arun Verma noted a correction to the agenda, whereby the
accreditation of the New Section on Structural Biology, Biochemistry
and Biophysics will be moved from Old Business to Section reports.

Motions to approve the minutes from the March and May Council
meetings were made (Wieland) and seconded (Gallik). Both motions
passed.

President Arun Verma formally welcomed Dr. Art Conway as
Executive Officer.

Officers reports:

President: Arun Verma passed out copies of his report.

A schedule of responsibilities for 2010-2011 was prepared and
posted on the Academy’s WEB site.

The memorandum of agreement with the Foundation of the
Flora of Virginia Project Inc has been formally executed.

Ms. Hillary E. Stewart has been hired as the new
administrative assistant

The letter to the Commonwealth’s Attorney General about
Prof. Mann has not been sent. Several drafts were generated;

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however, there did not seem to be any consensus as to the language
and intent.

The Academy is coordinating with the University of
Richmond for the next Annual Meeting. Drs. Verma, Conway, and
Mays visited the site in August, and are working with Dr. Bell and UR
officials to iron out details.

The Jeffers Memorial lecture at the next Annual Meeting will
be delivered by Dr. Cynthia Keppel, scientific and technical director
of the Hampton University Proton Therapy institute.

The Academy mourns the loss of Dr. Tom O, Sitz and
acknowledges his long time contributions to the academy including
serving as the president of the Academy during 1995-96. Recently he
retired from Virginia Tech. He was 65. He was a member of the
Archive Committee 2010-2013. Elsa Falls asked if there was some
way that the Academy could honor Dr. Sitz and his contributions to
the Academy. An “In Memoriam” is planned for the Journal, and Jim
O’Brien will be asked to place a notice in the news letter. It was
suggested that a scholarship at Virginia Tech be established in the
Biochemistry Department. An ad hoc committee was set up to follow
up on this: Marion Loebstein, Elsa Falls, Arum Verma and Jim
O’Brien volunteered for the committee. Arun Verma has already
contacted Virginia Tech. Also, a copy of the Journal with the “In
Memoriam” will be sent to his family.

President Elect: Mike Renfroe reported on the Fall Undergraduate
Research Meeting. There were a total of 8 presentations, of which 5
were funded. Leslie Harlacker discussed the biomechanics of Flint
knapping followed by a demonstration of the same. An announcement
about the awards and the projects will go out in the newsletter.

Vice President: Ralph Eckerlin reported that he verified the section
secretaries and their emails. He has prepared the Call for Papers for
the Annual Meeting and has included the new section, and has sent it
to Art Conway. He will be working with Art Conway to get the Call
sent out to members in January. All is on schedule. He did request
that the secretaries ensure that the section officers and their contact
information are up to date.

ACADEMY MINUTES

129

Susan Booth asked whether a letter could be sent indicating
the VAS support for VJAS, and also a letter requesting judges for
VJAS.

Secretary: Deborah O’Dell reminded council members that all
motions should be submitted to her in writing so that they can be
accurately recorded. She also reminded all members present to sign
in.

Treasurer: David Crosby had no report.

Executive Officer: Art Conway passed out the Income/Expense
Comparison No adjustments to budget requests are planned. Some
items may be adjusted based on past levels. The Executive Officer
noted that contributions listed 25,000 which came from and was
transferred to the VAS Trust. It was noted that the 2010 VJAS Budget
shows a surplus of $7000. Susan Booth gave some clarification on
the expenditures and history. It was noted that the overall budget
shows a negative balance which could be covered by this surplus.

Motion: Art Conway moved that the budget as presented be
approved as presented. Additionally, any surpluses in the VJAS
budget in 2010 be transferred over to the 2011 budget. Motion
seconded by Art Burke. Motion passed.

Marion Loebstein asked about funding for the Flora of
Virginia project. It was suggested that she should submit a request to
council or to the Fellows.

VJAS Director: Susan Booth gave a report on the VJAS. VJAS is
seeing an increase in requests for scholarships from the Virginia
Environmental Endowment. It was decided that section judges will
also serve as the judges for this scholarship. A concern is that projects
presented by High School students are still being judged in tandem
with those from Middle School students. Therefore, VJAS is
examining a model whereby students in grades 7-8 will be separated
from those in grades 9-12. She passed around a proposal detailing
this proposal. The Council discussed the pros and cons of the
proposal. The Executive Council recommended that VJAS be split
into two groups: grades 7-9 and grades 10-12. Any change would be

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effective as of the 2012 Annual Meeting. Since judges are hard to
find, it was suggested that high school teachers may serve as judges
for the Jr. High sections.

Committee Reports:

Committee reports were accepted from the Awards Committee,
Environment Committee, Flora of Virginia, Fundraising Committee,
Long Range Planning Committee, Membership committee,
Nominations committee, the Publications Committee, the Research
Committee, and the Trust Committee.

Archives: No report

Awards: No nominations were received by the Oct 1 st
deadline for Fellows or Honorary Life Members. This may be due to
the timing for the call for nominations. Currently it goes out in the
Call for Papers, in the spring for the following year. A change was
suggested that it be placed in the spring newsletters, and to send it out
also in Aug/September.

Constitution and Bylaws: no report

Environment: Richard Groover reported that there was not a
great response to their proposed symposium, so that has been shelved.
He expressed disappointment that the letter which was to be sent
regarding Dr. Mann was not sent. Some discussion ensued and it was
decided that VAS needs a statement regarding academic freedom.

Motion: (Wieland, O’Brien 2nd) “That the Executive committee draft
a policy statement which supports the National Academy of Science
position on Academic Freedom.” Motion passed unanimously.
This statement is to be placed on the VAS WEB site and in our
newsletter.

ACADEMY MINUTES

131

Fellows: No Report

Finance: Report under the budget

Flora of Virginia: Marion Lobstein provided a written report
on the progress of the Flora. She indicated that $200,000 was still
needed to bring the Flora to publication. It was asked whether VJAS
could hold a fundraiser to help with this.

Fundraising: The only fundraiser that is planned is the VJAS

run.

Long Range Planning: The future meeting sites are: 2011
University of Richmond (confirmed); 2012 Old Dominion University
in talks. Other sites are 2013 James Madison University, and 2014
Virginia Commonwealth University. Arun Verma has drafted a
“Requirements for Hosting a VAS/VJAS Annual Meeting” to provide
information to institutions who have not hosted an Annual Meeting.

Membership: Richard Groover passed out a written report.
This report shows that there has been an increase in membership
including institutional memberships. We need to continue to bring
new members into the Academy. The idea of sponsoring a business
advisory committee was raised.

Nominations: The committee is still finishing the slate for
new officers. A new treasurer needs yet to be confirmed.

Publications: A new editor for the news letter is needed.

Research committee: No report, but a replacement for Art
Conway is needed since he is now Executive Officer.

Science Advisory: no report

Science Education: David Hagan announced the annual
reception for outstanding scientists at the Science Museum of

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Virginia. Please contact him if you wish to attend. He passed out a
written report of activities, including a position paper by VSELA on

“Science and the use of the term “STEM”.

Trust Committee: Elsa Falls passed out a summary of the
trust accounts and a Historical Account Balance. She reported that
the funds are moving in the right direction. It was noted that the Fund
for the Future has been built up, and we should consider that the
Future is now and that perhaps it is appropriate to begin withdraw of
funds. The council charged the Trust committee with examining the
Fund for the Future and possible disbursal of said funds.

VJAS: Report already given under the VJAS directors report,
nothing to add.

WEB Site: no report.

Section Reports

Aeronautical and Aerospace Sciences: No report

Agriculture, Forestry and Aquaculture: No report

Astronomy, Mathematics and Physics with Materials
Science: No report

Biology with Microbiology: No report
Biomedical and General Engineering: all is well
Botany: Had a good meeting a JMU
Chemistry: no report
Computer Science: No report

ACADEMY MINUTES

133

Education: David Hagen passed out a written report of
activities and is reported under the committee reports above.

Environmental Science: Is planning a stronger outreach to
UR with Environmental Science majors/minors to present at the
annual meeting.

Medical Science: no report

Natural History and Biodiversity: There were 5 papers
presented at the Annual Meeting, and the section wants to do a better
job at recruiting papers. 2010 is named the Year of Biodiversity.
Thomas Lovejoy (George Mason U) will be a guest speaker for the
section.

Psychology: present
Statistics: no report

Structural Biology, Biochemistry and Biophysics: Ellis Bell
passed out a written report. They are planning a special symposium
on Education in Molecular Biology for the next meeting to cover
possibly teaching science at the college level. They are looking into a
grant from NSF to help support this symposium.

Old Business: No old Business

New Business:

Jim O’Brien wanted to encourage all to support the Science
Museum of Virginia and its “green” initiative.

Carolyn Conway announced that dues renewal notices will be
going out in the email.

Announcements:

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VIRGINIA JOURNAL OF SCIENCE

Arun Verma thanked Richard Groover for organizing today’s meeting.
Next Council meeting is 19 March, 2011, location TBD.

AAAS sites have information on and seminars on policy

MOTION TO ADJOURN: Mike Renfroe, Werner Wieland 2 nd .
Motion carried.

Meeting was adjourned at 1:18 pm.

Respectfully submitted,

Deborah A. O’Dell, Secretary, VAS

Motions considered and acted on (other than minute approval
and adjournment):

1. Motion: Art Conway moved that the budget as presented be
approved as presented. Additionally, any surpluses in the VJAS
budget in 2010 be transferred over to the 201 budget 1. Motion
seconded by Art Burke. Motion passed.

2. Motion: (Wieland, O’Brien 2nd) “That the Executive committee
draft a policy statement which supports the National Academy of
Science position on Academic Freedom.” Motion passed
unanimously

HORSLEY AWARD

135

The Horsley Award paper for 2011

Eswar Prasad R. Iyer, Srividya Chandramouli Iyer, Ramakrishna
Meduri, Dennis Wang, and Daniel N. Cox

Department of Molecular and Microbiology, Krasnow Institute for
Advanced Study, George Mason University, Manassas, VA

Class-specific profiling and in vivo RNAi screen reveal complex
transcriptional regulatory networks mediating dendritic architecture

NOTES

NOTES