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Full-Text Articles in Animal Sciences

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita Jan 2024

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …


Factors Associated With Acoustic Bat Presence During Spring Emergence In The Appalachian Mountains Of Western Virginia, Emily Kirk Pody Jan 2024

Factors Associated With Acoustic Bat Presence During Spring Emergence In The Appalachian Mountains Of Western Virginia, Emily Kirk Pody

Theses, Dissertations and Capstones

Studies of threats that bats face during hibernation have increased in response to white-nose syndrome (WNS), a fungal disease that has ravaged North American bat populations. However, impacts of WNS on bat ecology during spring emergence, when bats are potentially recovering from infection and allocating resources for reproduction, is relatively understudied. As more bat species become listed at the federal and state level, the need to understand the factors associated with spring emergence is critical for improving conservation guidelines and habitat management practices. Acoustic monitoring is an efficient method for monitoring bat presence for prolonged periods of time, giving biologists …


Addressing Water Hyacinth (Pontederia Crassipes) Impacts On Aquatic Biota In Lake Okeechobee, Joseph Salerno Dec 2023

Addressing Water Hyacinth (Pontederia Crassipes) Impacts On Aquatic Biota In Lake Okeechobee, Joseph Salerno

All HCAS Student Capstones, Theses, and Dissertations

The incursion of water hyacinth, Pontederia crassipes in Lake Okeechobee has resulted in management systems to be implemented to reduce the coverage of the invasive macrophyte. Its residence in the Lake Okeechobee ecosystem and the effects it has on organisms in the lake, whether it be positive or harmful is unknown. This study attempted to assess the potential effects that water hyacinth has on aquatic biota in Lake Okeechobee. Biotic data were collected on open water, water hyacinth covered, and native vegetation covered habitats via hook-and-line fishing, electrofishing, baited minnow traps, and the sampling of plant roots over a thirteen-month …


An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, Justin C. Hunt Jul 2023

An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, Justin C. Hunt

Biology Theses

Amphibians are a unique class of organisms with a very long and storied evolutionary history of survival. Many modern amphibian clades occupy several vital ecological roles within their native freshwater environments. One of these roles, typically includes functioning as an ecological indicator species, whereby the presence of stable and diverse populations of many amphibian species, including salamanders, within a freshwater ecosystem have long been considered ecological indicators of good habitat quality and stable ecosystem health. Similarly, salamanders also function as important members of their local food webs and act as valuable mediators of complex trophic hierarchies to facilitate nutrient cycling …


Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi Jan 2023

Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi

Theses and Dissertations (Comprehensive)

Invertebrate drift is a key process that potentially affects multiple levels of food web organization within stream environments. However, our understanding of the mechanistic drivers of drift in high latitude streams and subsequent bottom-up control that drift may have on fish predators in these environments remains understudied. This project aimed to gain the baseline knowledge of how drift functions across two major high latitude ecozones, the boreal forest and tundra, and how those possible differences in drifting community characteristics may impact drift-feeding Arctic grayling (Thymallus arcticus). These objectives were accomplished by characterizing stream environments across both ecozones, sampling …


Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum May 2022

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …


Understanding Caribou Population Cycles, Jack R. St. John Jan 2022

Understanding Caribou Population Cycles, Jack R. St. John

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The complex population dynamics of caribou (Rangifer tarandus) were studied to determine the patterns of their population cycles and the processes driving them. It is well established, via previous archaeological research and Indigenous knowledge, that large migrating caribou herds found in and around the tundra at northern latitudes experience population boom and busts roughly every several decades. However, the processes driving the dynamics of these cycles are relatively unknown, which makes managing caribou herds for recreational and subsistence harvests difficult. It has been hypothesized that a combination of intrinsic and extrinsic factors shape these cycles, with density-dependence, predation, …


The Effect Of Changing Substrate On Arctic Aquatic Invertebrates Abundance, Tom Dolman Apr 2021

The Effect Of Changing Substrate On Arctic Aquatic Invertebrates Abundance, Tom Dolman

Michael D. Wilson Symposium

Climate change is directly affecting tundra ecosystems in northern regions, and warming temperatures have caused discontinuous permafrost and thawing sediments across the region. This project investigates how increasing erosion and the foraging patterns of migratory snow geese may degrade habitat for aquatic invertebrates in the upper Mast River, located in Wapusk National Park, Manitoba, Canada. In the past two decades, many of the important species of aquatic invertebrates have shown declines. Declining invertebrate populations are predicted to affect aquatic ecosystems and decrease the resources available to shorebirds and waterfowl, which breed and migrate through this area.


Population Fluctuation And Diurnal Time Budgeting Of White-Headed Duck (Oxyura Leucocephala) During Winter At Garaet Hadj Tahar (Skikda, North East Algerian), Merzoug Seyf Eddine, Abdi Soumia, Bara Mouslim, Houhamdi Moussa Mar 2021

Population Fluctuation And Diurnal Time Budgeting Of White-Headed Duck (Oxyura Leucocephala) During Winter At Garaet Hadj Tahar (Skikda, North East Algerian), Merzoug Seyf Eddine, Abdi Soumia, Bara Mouslim, Houhamdi Moussa

Journal of Bioresource Management

This study was focused on the ecology and behavior of the White-headed Duck (Oxyura leucocephala) at Garaet Hadj Tahar (Guerbes-Sanhadja, North East of Algeria). Sampling was carried out during two wintering seasons (2017-2018 and 2018-2019). High number of this duck was recorded in 2018/19 (350 individuals). We observed two Oxyura population, the first sedentary, and the second, hosted the Garaet during the wintering season. Diurnal time budget was dominated by the comfort activities the sleeping with a rate of 39.13%. Following by swimming (37.76%), feeding (17.59%) grooming (4.58%), courtship ritual (0.56%) and flying (0.38%). The feeding of white-headed …


Beyond Predation: How Do Consumers Mediate Bottom-Up Processes In Ecosystems?, Bradley Austin Strickland Jun 2020

Beyond Predation: How Do Consumers Mediate Bottom-Up Processes In Ecosystems?, Bradley Austin Strickland

FIU Electronic Theses and Dissertations

By eating and scaring prey, predators can exert strong effects on communities and ecosystems. In addition, some animals may physically alter habitats and may recycle nutrients through digestion, both of which affect resources available to producers. Bottom-up effects initiated by large predators have not been well-studied and could prove to be important for understanding food webs and how ecosystems function. American alligators (Alligator mississippiensis) are abundant mobile predators that are capable of engineering aquatic habitats by moving organic material across ecosystem boundaries and creating and maintaining alligator ponds. In this dissertation, I documented the scale of ecological impacts …


Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele May 2020

Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele

Electronic Theses and Dissertations

Circadian clocks enable coordination of essential biological and metabolic processes in relation to the 24-hour light cycle. However, there are many habitats that are not subject to this light cycle, such as the deep sea, arctic regions, and cave systems. This study analyzes the circadian pattern of isolated populations of a subterranean spider, Meta ovalis from two Tennessee caves and five Indiana caves. Locomotor activity was recorded with TriKinetics LAM50 Locomotor Activity Monitor under a 12-hour light (L), 12-hour dark (D) (LD 12:12) cycle preceding total darkness (DD). Significant differences were found within and among populations found in Tennessee cave …


Black Vulture Conflict And Management In The United States: Damage Trends, Management Overview, And Research Needs, Bryan M. Kluever, Morgan Pfeiffer, Scott C. Barras, Brett Dunlap, Lee A. Humberg Jan 2020

Black Vulture Conflict And Management In The United States: Damage Trends, Management Overview, And Research Needs, Bryan M. Kluever, Morgan Pfeiffer, Scott C. Barras, Brett Dunlap, Lee A. Humberg

USDA Wildlife Services: Staff Publications

Contrary to rapid declines of many vulture (Accipitridae, Cathartidea) species worldwide, black vulture (Coragyps atratus) populations are increasing and expanding their range in North America. Vultures exhibit complex behaviors and can adapt to any human-dominated landscape or land use. These traits, combined with population growth and range expansion, have contributed to increased human–vulture conflicts. Our goal was to summarize the current status and trends in human–black vulture conflicts (hereafter human– vulture conflicts), review available management strategies, identify knowledge gaps, and provide recommendations to enhance management and understanding of this species and the associated conflicts. We found human–vulture conflicts …


Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding Dec 2019

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …


Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan May 2019

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …


Where Birds Chill: An Assessment Of The Habitat Preferences Of Birds Overwintering In Hudson Valley Forests, Elizabeth Claire Axley Jan 2019

Where Birds Chill: An Assessment Of The Habitat Preferences Of Birds Overwintering In Hudson Valley Forests, Elizabeth Claire Axley

Senior Projects Spring 2019

Many avian species overwinter in eastern North America; however, studies on bird populations are rarely undertaken during this critical survival time, and little is known as to their habitat preferences and foraging behavior. In this observational study, we performed a survey of birds overwintering in the Hudson Valley’s temperate, primarily-deciduous forests, assessing avian populations’ habitat preferences through the vegetative structural variables surrounding overwintering birds as they forage. Our results suggest that high canopy cover is critically important to predicting overwintering bird occupancy on a microhabitat scale. Moreover, overwintering birds preferentially occupy forest plots not dominated by sugar maples, in spite …


The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley Aug 2018

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of …


The Real Snowbirds Of South Florida: Using Citizen Science To Assess The Ranges Of South Florida's Overwintering Birdsh, Alexander V. Levine Jun 2018

The Real Snowbirds Of South Florida: Using Citizen Science To Assess The Ranges Of South Florida's Overwintering Birdsh, Alexander V. Levine

FIU Electronic Theses and Dissertations

The overwintering ranges of North American bird populations are shifting and the winter ranges of south Florida’s landbirds remain understudied. Expert-drawn range maps used for scientific studies and environmental public policy could therefore be depicting inaccurate ranges for many migratory birds. This study used citizen science data from eBird (2001–2017) to evaluate patterns in overwintering avian species richness and identify discrepanciesin expert-drawn species range maps for overwintering passerines in south Florida. Most of Florida’s overwintering bird species were sighted in south Florida. Of the species observed there between 2001 and 2017, 66% had range map discrepancies. Fifteen target species were …


Population Characteristics Of Human-Commensal Rodents Present In Households From Mérida, Yucatán, México, Jesús Alonso Panti-May, Silvia F. Hernández-Betancourt, Marco A. Torres-Castro, Carlos Machaín-Williams, Nohemi Cigarroa-Toledo, Lorenzo Sodá, Gabriela López-Manzanero, Josué R. Meza-Sulú, Victor M. Vidal-Martínez Sep 2016

Population Characteristics Of Human-Commensal Rodents Present In Households From Mérida, Yucatán, México, Jesús Alonso Panti-May, Silvia F. Hernández-Betancourt, Marco A. Torres-Castro, Carlos Machaín-Williams, Nohemi Cigarroa-Toledo, Lorenzo Sodá, Gabriela López-Manzanero, Josué R. Meza-Sulú, Victor M. Vidal-Martínez

MANTER: Journal of Parasite Biodiversity

Anthropocommensal rodents live in close proximity to humans in many habitats around the world. They are a threat to public health because of the pathogens they carry. Recent studies in Mérida, Yucatán, México, have shown that commensal rodents harbor potential zoonotic pathogens such as bacteria, helminths, and viruses. In this study, we describe reproductive and demographic parameters of house mice and black rats present in households from Mérida, Yucatán, México, a municipality located in a tropical region in southern México. Rodents were trapped in 142 households within the municipality of Mérida from 2011 to 2014. A total of 832 rodents …


Ecology Of Two Reintroduced Black Bear Populations In The Central Appalachians, Sean Mccarthy Murphy Jan 2016

Ecology Of Two Reintroduced Black Bear Populations In The Central Appalachians, Sean Mccarthy Murphy

Theses and Dissertations--Animal and Food Sciences

Reintroduced populations are vulnerable to demographic and environmental stochasticity, deleterious genetic effects, and reduced population fitness, all of which can increase extinction probability. Population viability is principle to determining the status of reintroduced populations and for guiding management decisions. To attempt to reestablish black bear (Ursus americanus) populations in the central Appalachians, two reintroductions using small founder groups occurred during the 1990s in the Big South Fork area along the Kentucky-Tennessee border (BSF) and in the Jefferson National Forest along the Kentucky-Virginia border (KVP). My objectives were to estimate demographic and genetic parameters, and to evaluate long-term viability …


The Characterization Of A Vital Wisconsin Waterway: A Biological Assessment Of The Lower Fox River From 2006-2014, Emily L. Kiehnau Jun 2015

The Characterization Of A Vital Wisconsin Waterway: A Biological Assessment Of The Lower Fox River From 2006-2014, Emily L. Kiehnau

Lawrence University Honors Projects

The Lower Fox River has historically been used as a navigational crossroads, a waste disposal system, and source of hydroelectric power. Over the years, heavy use of the river has negatively affected water quality and the overall health of the system. Unhealthy rivers cannot function properly. Biological assessment based on animal surveys are often used to determine river health. I used data from the Lawrence University and Fox River Navigational System Authority invasive species-monitoring project to explore how the distribution of animals in the Fox River has changed over time and across locations. Monitoring surveys have taken place between June …


Provisioning And Its Effects On The Social Interactions Of Tibetan Macaques (Macaca Thibetana) At Mt. Huangshan, China, Brianna I. Schnepel Jan 2015

Provisioning And Its Effects On The Social Interactions Of Tibetan Macaques (Macaca Thibetana) At Mt. Huangshan, China, Brianna I. Schnepel

All Master's Theses

The dispersal patterns of food resources has a significant effect on the composition of primate groups and social interactions within those groups. Humans often alter the dispersal of food. Non-humans often use affiliative behaviors to elicit tolerance or support from other group members. I investigated whether provisioned food resources alter the social interactions and group dynamics of Macaca thibetana. All-occurrence sampling and scan sampling were used for data recorded by camera traps. Trail-cameras were placed at six locations that contain natural and human food resources and recorded 60-second videos. Social behavior and proximity of the monkeys were recorded. I …


The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts Dec 2014

The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts

Mark P. Simmonds, OBE

The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation …


Comparing Population Density Estimation Techniques For Columbia Black-Tailed Deer (Odocoileus Hemionus Columbianus): Fecal Standing Crop And Distance Sampling Methods, Jubilee D. Brenneman Jun 2014

Comparing Population Density Estimation Techniques For Columbia Black-Tailed Deer (Odocoileus Hemionus Columbianus): Fecal Standing Crop And Distance Sampling Methods, Jubilee D. Brenneman

Honors Projects

I estimated deer density and population size on Blakely Island, WA, using the fecal standing crop (FSC) method described by Martin et al. (2011). I compared the FSC method with a well established and broadly applicable estimation method, distance sampling. Additionally, architecture of a commonly browsed shrub, Ocean Spray (Holodiscus discolor), was measured as an indicator of browsing pressure. Fecal standing crop was estimated by counting pellet groups along 26, 100 x 2m line transects. Deer density was estimated using these data and the equation derived by Martin et al. (2011). Distance sampling consisted of recording perpendicular distance …


Natural History Of A Population Of Wood Turtles (Glyptemys Insculpta) In West Virginia, Jessica Curtis Jan 2014

Natural History Of A Population Of Wood Turtles (Glyptemys Insculpta) In West Virginia, Jessica Curtis

Theses, Dissertations and Capstones

The Wood Turtle (Glyptemys insculpta) is listed as vulnerable in West Virginia and only occurs in the Eastern Panhandle. The study population is unique in West Virginia because it occurs at a much higher mean elevation than other Wood Turtle populations in the state. The primary objective of this study was to determine if, and to what extent, altitude affected this population’s ecology. Turtles were located with opportunistic surveys and captured by hand. I located 31 turtles: 18 males, and 13 females. Turtles were captured a total of 68 times. Ratio of males to females did not differ significantly from …


The Population Dynamics Of Two Rodents In Two Coastal Marshes In Virginia, Robert K. Rose, John A. March Jan 2013

The Population Dynamics Of Two Rodents In Two Coastal Marshes In Virginia, Robert K. Rose, John A. March

Virginia Journal of Science

The communities of small mammals were evaluated for 13 months with capture-mark-recapture methods in two Spartina-Juncus marshes of the Atlantic coast in Northampton County, Virginia. Small mammals were trapped for three days each month using live traps placed on floats on two study grids. Two rodents were numerically dominant (~90% of small mammals) there: marsh rice rat, Oryzomys palustris, and meadow vole, Microtus pennsylvanicus. Monthly estimates of population density were greater for rice rats (peak: 45/ha) than for those of meadow voles (peak: 30/ha). Survival rates were generally low, especially for rice rats, indicating highly vagile populations. Both …


First Record Of Pond Sliders (Trachemys Scripta Scripta And T. S. Elegans) At Fredericksburg, Virginia With Observations On Population Size, Age And Growth, Werner Wieland, Yoshinori Takeda Jan 2013

First Record Of Pond Sliders (Trachemys Scripta Scripta And T. S. Elegans) At Fredericksburg, Virginia With Observations On Population Size, Age And Growth, Werner Wieland, Yoshinori Takeda

Virginia Journal of Science

We conducted a turtle mark-recapture program within a 160 m stretch of the Fredericksburg Canal with standard, baited hoop nets from May to July 2012 to determine if a population of the introduced Red-eared Slider (Trachemys scripta elegans) and Yellow-bellied Slider (Trachemys s. scripta) are established in this area. We captured and marked nine Red-eared Sliders (1 male, 8 females) and estimated a population size of 23 individuals. Most were reproductively mature. The established population in the canal may be a source of introduction into the Rappahannock River.


Osteology, Natural History Notes, And Phylogenetic Relationships Of The Poorly Known Caribbean Frog Leptodactylus Nesiotus (Anura, Leptodactylidae), María Laura Ponssa, Michael J. Jowers, Rafael O. De Sá Oct 2010

Osteology, Natural History Notes, And Phylogenetic Relationships Of The Poorly Known Caribbean Frog Leptodactylus Nesiotus (Anura, Leptodactylidae), María Laura Ponssa, Michael J. Jowers, Rafael O. De Sá

Biology Faculty Publications

The Leptodactylus melanonotus group consists of 15 species, but references to skeletal characters are available for only three species: L. leptodactyloides, L. melanonotus, and L. diedrus. Leptodactylus nesiotus is a member of the melanonotus group known only from the type locality, Bonasse swamp, on the Southwestern peninsula of Trinidad, Trinidad and Tobago. This species has been categorized as vulnerable given its restricted distribution. Herein, we report the adult osteology of L. nesiotus, the skeletal characters are compared with the available data from other Leptodactylus species. A phylogenetic analysis recovers a paraphyletic L. melanonotus group relative to the L. …


Environmental And Endogenous Factors Influencing Emigration In Juvenile Anadromous Alewives, Benjamin I. Gahagan, Eric T. Schultz, Katie E. Gherard Jan 2010

Environmental And Endogenous Factors Influencing Emigration In Juvenile Anadromous Alewives, Benjamin I. Gahagan, Eric T. Schultz, Katie E. Gherard

EEB Articles

We analyzed juvenile anadromous alewife migration at Bride Lake, a coastal lake in Connecticut, during summer 2006 and found that migration on 24-hour and seasonal timescales was influenced by conditions of the environment and characteristics of the individual. To identify environmental cues of juvenile migration, we continuously video recorded fish at the lake outflow and employed information-theoretic model selection to identify the best predictors of daily migration rate. More than 80% of the approximately 320,000 juveniles that migrated from mid-June to mid-August departed in three pulses lasting one or two days. Pulses of migration were associated with precipitation events, transient …


Conservation Implications Of A Marbled Salamander, Ambystoma Opacum, Metapopulation Model, Ethan B. Plunkett Jan 2009

Conservation Implications Of A Marbled Salamander, Ambystoma Opacum, Metapopulation Model, Ethan B. Plunkett

Masters Theses 1911 - February 2014

Amphibians are in decline globally and a significantly greater percentage of ambystomatid salamander species are in decline relative to other species; habitat loss contributes significantly to this decline. The goals of this thesis is to better understand extinction risk in a marbled salamander (ambystoma opacum) population and how forestry effects extinction risk. To achieve this goal we first estimated an important life history parameter (Chapter 1) then used a metapopulation model to estimate population viability and determine what aspects of their life history put them most at risk (Chapter 2) and finally predicted extinction risk in response to hypothetical forestry …


Ecology And Morphological Comparison Between Rough Greensnakes (Opheodrys A. Aestivus) And Eastern Smooth Greensnakes (Opheodrys V. Vernalis) In West Virginia, Timothy Earl Baldwin Jan 2007

Ecology And Morphological Comparison Between Rough Greensnakes (Opheodrys A. Aestivus) And Eastern Smooth Greensnakes (Opheodrys V. Vernalis) In West Virginia, Timothy Earl Baldwin

Theses, Dissertations and Capstones

Since 1971, documented Rough Greensnake (Opheodrys aestivus) occurrences in West Virginia have declined from approximately 100 to less than 20 occurrences in the last 10 years. In contrast to the decline of Rough Greensnakes in WV, Smooth Greensnake (O. vernalis) populations appear to be stable over the same period of time. Historic sites from the West Virginia Biological Survey were cross referenced with habitat descriptions in published literature to establish research locations. One hundred nineteen Rough and Smooth Greensnakes were measured for snout-vent length and total body length, and of these, 78 were measured in detail for external head morphology …