Nora Purcell
animal industry.
The stress related to confinement in an unknown environment can create
destructive behaviors, leading to a search for an effective remedy for
this anxiety. Herbal remedies, valerian in particular, have become
increasingly popular as treatments for insomnia and anxiety, but there
are very few trials conducted on species other than humans and rats.
Therefore, my objective was to determine whether a valerian containing
biscuit had an effect on the behaviors of kenneled dogs. Using 69 dogs
in 3 separate trials, a two-hour pre-treatment observational study was
performed, when the status of vocalization, posture, and movement was
recorded for each dog. Afterwards, to maintain a double-blind study, an
assistant randomly chose half of those dogs, and they received the
amount of valerian product determined by their weight. The control
group received a placebo biscuit. After one hour, a post-treatment
observational session was performed. The number of positive
vocalization, movement, and active behaviors changed significantly
between the two observational sessions for both the control and
treatment groups (p values all .0001 or less using a Wilcoxon
matched-pairs signed-rank test) except for the vocalization in the
control group (p value= .4961). The difference between the control and
treatment groups was also significant (p value= .0086, .0227, and .0109
respectively, using a Mann-Whitney test). Post-prandial depression and
influence of calmer dogs can explain the general decrease in active
behaviors in both treatments. These results suggest, however, that the
valerian product contributed to the greater decrease of vocalization,
movement, and active behaviors.
The
loggerhead sea turtle (Caretta caretta)
is a reptile
species with federally threatened status in the United States
(US). Adult female loggerheads use coastal beaches of the
southeastern states of the US every year from May to August for
nesting. They crawl to the dunes at night to lay a clutch eggs
then use visual light cues and the downward slope of the dunes to
navigate back to the sea. Beginning in July, hatchling
loggerheads emerge from the nests at night and use the same cues to
find the ocean. Both adult females and hatchlings are attracted
to artificial light sources. Light pollution in coastal areas
with heavy human population contributes to hatchling disorientation and
resultant mortality. In order to promote cost effective light
bulbs that limit hatchling disorientation due to artificial lighting,
this study compared the sea-finding ability of hatchlings under two
light treatments: a “turtle friendly” light-emitting diode (LED), and a
control with no artificial light source. Though data are limited
and subject to confounding variables, Watson’s U2 test showed no
significant difference between the sea-finding ability of hatchlings
under the two light treatments. However, qualitative observations
showed that hatchlings under the “turtle friendly” amber LED treatment
crawled in circles and up the slope of the dunes before choosing a
direction while hatchlings under no artificial light headed towards the
sea without hesitation. These observations suggest that the amber
LED is not completely “turtle friendly.” Further data collection
in future nesting seasons is warranted to strengthen this study.
in the
peppermint oil. The monoterpene composition can be affected by several
factors including the presence of other organisms. Peppermint and
wine-cap Stropharia (Stropharia
rugoso-annulata) were grown in pots in a growth chamber from
September through October of 2008 in order to study whether co-planting
would affect the plants and mushroom production. How many survived?
Eleven of the twelve plants in the experimental group died. Three of
the twelve plants in the peppermint control group, one in a pot
contaminated by the Stopharia, also died. The fungi and water stress
may have contributed to the fatalities. Liquid extracts were prepared
from six fresh leaf pairs collected from surviving control plants.
Samples were analyzed using gas chromatography-mass spectrometry,
focusing on the presence of limonene, menthol, menthone, menthofuran
and pulegone. An external calibration curve was used to measure the
monoterpene concentrations in the samples. A total of 187 mushrooms
were collected from 11 pots: one fungi control pot, one peppermint
control pot and nine experimental pots. Peppermint extracts varied in
monoterpene composition and concentration, though limonene was present
in all samples. Monoterpene concentrations were consistent with those
noted in other papers. Variation in monoterpene composition between
leaf pairs was also consistent with other literature.
TH are important in glucose regulation in which they
increase glucose uptake from the blood. Epinephrine (E) and
norepinephrine (NE) also participate in glucose transport by causing
the release of glucose to the blood. The effects that TH, E and
NE have on glucose accessibility are necessary for survival in an
emergency. This study is part of a larger project addressing the
interplay of hormones and EDCs; the data collected will identify normal
levels of TH, NE, E, and glucose from juvenile Alligator mississippiensis in a low
EDC exposure site. Nine juvenile Alligator mississippiensis were
caught from Orange Lake in Florida and blood samples were taken from
each specimen at 0, 2, 4, and 8 minutes after capture during
restraint. TH and glucose levels will be measured at the
University of Florida; E and NE will be measured at WWC after alumina
extraction by high performance liquid chromatography with
electrochemical detection. An EG&G Princeton Applied Research
Electrochemical Detector Model 400 with a Bioanalytical Systems dual
glassy carbon electrode has been setup for this analysis. Calibration
curves for NE, E, and an internal standard have been made with linear
regression lines having high R2 values with an average relative
standard deviation less than 5%. The alumina extraction method is
being optimized using dog blood samples. The method can detect at
concentration in pg/mL range which is 1000 times lower than expected
values in alligator samples. The data collected from this study
are to be compared with alligators known to be exposed to EDCs.
The overall goal of the project is to indicate the ability of an Alligator mississippiensis to react
appropriately in an emergency.
of sustainable agriculture is soil fertility. One
way to increase soil fertility is to plant cover crops. Cover crops are
crops planted and grown but not harvested for human consumption; they
act as living mulch. Cover crops improve the soil by adding
organic matter, increasing the water holding capacity, preventing soil
erosion, adding nitrogen, suppressing weeds, and soil moisture
conservation. Other benefits of cover crops include reducing use
of fertilizer costs, reducing the use of pesticides or herbicides, and
protecting water quality. To develop an effective cover crop
system, it is necessary to find a species that is adapted to the local
climate and latitude, can easily be killed, and does not compete with
the cash crop. The objective of this study was to investigate the
biomass production, winterkill date, and effectiveness of weed
suppression of three legumes, two grain, and one broadleaf cover crop
for minimal tillage production in the Warren Wilson College Garden. Six
winter crop and weed biomasses were collected on 3 November 2008, 13
October 2008, 1 December 2008, and 5 April 2009. Average weights
were calculated and graphed. The results indicated that rapeseed
oil radish produced the greatest amount of biomass and suppressed the
most weeds, but decomposed quickly. The legumes produced the smallest
amount of biomass and suppressed the least weeds in the fall. The
grains acted similarly, resulting in the second greatest biomass
production and weed suppression in the fall. In order to
accurately determine which crop to plant, more research is needed to
look at growing patters over a number of winter seasons. A mixture of
barley, oats, and spring field pea would meet the goals a substantial
biomass, effective weed suppression, a late winterkill date, nitrogen
fixation, and residual dead biomass in the spring.| Abstract: The beaches of Long Island, New York act as important breeding grounds for the Piping Plover(Charadrius melodus), yet human development of these beaches poses a considerable threat to the conservation of this listed species. Conservation management efforts must take into account the reproductive ecology of the species. We investigate how reproductive success and fecundity of the breeding population changes over the course of the breeding season. Data collected during breeding seasons starting from 1999 through 2008 by The Nature Conservancy on Long Island provide evidence that initial nesting attempts (first nests) exhibit the same fecundity and likelihood of success as attempts to replace a lost nest (renests); there were no significant differences between the two in terms of average clutch size (P = 0.55), hatching success (P = 0.58), or fledging success (P = 0.46). The data also suggest that nests that hatch earlier tend to feature a larger clutch size (P < 0.001) and hatch more eggs (P < 0.001). However, the number of chicks fledged from a nest was not associated with hatch date (P = 0.07). Research on other sites has suggested that more young fledge from nests that are laid earlier in the season. If so, we suggest that this may be more attributable to higher hatching success than to higher fledging success from amongst the chick population. Because of this intraseasonal decline in breeding capacity, likely due to greater challenges from human development and life history demands, the early part of the season is critical for breeding success and should be a priority for conservation management. | Nora Purcell
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| Amy Rowlatt Electrophoretic Variation of Malate Dehydrogenase in Lysimachia fraseri. May 4, 2009 Mentor: Dr. Jeff Holmes Abstract: Lysimachia fraseri (Fraser’s Yellow Loosestife) is a rare plant belonging to the Primulaceae (Primrose) family, endemic to the central and southeastern United States. North Carolina is home to the majority of the 86 confirmed extant populations nationwide. The cause of this species imperilment is unknown, but an understanding of the genetic variation among and between subpopulations of L.fraseri is essential for conservation. Using starch gel electrophoresis, the metabolic enzyme malate dehydrogenase (MDH), was analyzed for polymorphism among and between individuals from two groups of L. fraseri residing on the Warren Wilson College Campus. The enzymatic activity in leaf tissue from eighteen individuals from each of the potential sub populations was assayed. Results indicate that MDH is expressed from a minimum of two loci, one of which is polymorphic. Additionally, one of the two plots sampled expressed a unique phenotype, indicating the presence of greater genetic diversity within that plot. This suggests that the two groups of L. fraseri may have emerged as separate subpopulations of a larger metapopulation and may have been reproductively isolated for some time. |
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Abstract:
Crayfish, also called crawfish, crawdads, or mudbugs, are
freshwater crustaceans closely related to lobsters. Despite their
ecological importance as decomposers, predator, and prey, many issues
threaten their rich diversity. Threats include: habitat destruction,
pollution, and nonnative invasive crayfish, which threaten native
crayfish by either out competing or hybridizing with them. To my
knowledge, it seems that there is no consensus on which technique for
crayfish capture is most effective. In this study I sought to test the
effectiveness of four different baits as used in minnow traps. Twelve
sites along Bull Creek and the Swannanoa River on the Warren Wilson
College campus, NC, were set with minnow traps, which were baited
randomly either with sardines and other fish pieces, catfood, a live
crayfish, or no bait. After checking these traps every two days from
February to April 2009, the mean numbers of crayfish caught by each
treatment were compared using an ANOVA test. With a p-value of .0254 it
was found that the sardine treatment differed significantly form the
crayfish treatment. When comparing just the treatments as tested at the
Bull Creek sites, a p-value of .0103 suggests that there was a
significant difference between not only the sardine and crayfish
treatment, but the sardine and control treatments as well. A comparison
of the mean number of crayfish caught at the different sites was
inconclusive despite the fact that the Swannanoa river sites caught no
crayfish. This study thus concludes that dead fish is most likely the
most effective bait of the four treatments. Due to the fact that so
many crayfish could be caught in one trap at the same time it would
seem also that they have little aversion to a baited trap that is
already occupied. Choosing a reliable site greatly influences the
effectiveness of the minnow trap no matter the bait used. Hopefully
this knowledge can aid crayfish research in the future. Since threats
posed to crayfish biodiversity are in urgent need of attention,
researching and understanding species ranges and the nature of
hybridization is essential.