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Sources Of Ecologically Important Trait Variation In Mosquitofish (Gambusia Affinis And Gambusia Holbrooki), Heather Ann Arnett 2016 University of Maine

Sources Of Ecologically Important Trait Variation In Mosquitofish (Gambusia Affinis And Gambusia Holbrooki), Heather Ann Arnett

Electronic Theses and Dissertations

The study of contemporary evolution and eco-evolutionary dynamics is classically defined in terms of genetic evolution, but the actual suite of processes driving contemporary trait change is likely much more complex than often credited. This dissertation considers additional mechanisms of trait change that might be important to an emerging model system for study of contemporary evolution and eco-evolutionary dynamics. Specifically, the research focuses on phenotypically plastic and demographic trait variation in Eastern and Western Mosquitofish (Gambusia affinis and G. holbrooki) facing the major ecological gradient of predation risk. Plasticity experiments employed a common-garden rearing design to manipulate fish …


Population And Morphological Changes In American Kestrels Through Space And Time, Teresa E. Ely 2016 University of Nebraska-Lincoln

Population And Morphological Changes In American Kestrels Through Space And Time, Teresa E. Ely

School of Biological Sciences: Dissertations, Theses, and Student Research

A once common raptor, the American kestrel (Falco sparverius) has experienced population declines in the last two decades throughout North America. Many hypotheses exist about the decline, including mortality from West Nile virus, rodenticide poisoning, climate change, an increase in predators, and core habitat loss or degradation, which could influence food availability. Food availability is key to raptor survival and reproduction, and changes in food availability throughout the year can have lifelong effects on size and body condition. Here we examine how morphology, specifically mass and wing chord, has changed at seven migration sites throughout North America as …


Sea Turtle Conservation: Reviewing The Efficacy Of Land- And Sea-Based Management Strategies For Loggerhead (Caretta Caretta) And Leatherback (Dermochelys Coriacea) Sea Turtles, Glenn D. Goodwin 2016 Nova Southeastern University

Sea Turtle Conservation: Reviewing The Efficacy Of Land- And Sea-Based Management Strategies For Loggerhead (Caretta Caretta) And Leatherback (Dermochelys Coriacea) Sea Turtles, Glenn D. Goodwin

HCNSO Student Capstones

As cosmopolitan species, loggerhead and leatherback turtles are confronted with a multitude of threats as they progress through their respective life stages. These range from depredation and poaching of eggs, hatchlings, and females on nesting beaches, to incidental hooking in pelagic longline fisheries and capture in trawl fisheries. Some threats are species specific on regional scales, though most impact both species. To confront these threats, various conservation strategies have been developed and implemented, including monitoring and caging of nests and changes to hook shape and trawl design. Here, current conservation methods are presented and discussed on a global scale for …


Reef Fish Spatial Distribution And Benthic Habitat Associations On The Southeast Florida Reef Tract, Dana Fisco 2016 Nova Southeastern University

Reef Fish Spatial Distribution And Benthic Habitat Associations On The Southeast Florida Reef Tract, Dana Fisco

HCNSO Student Theses and Dissertations

The Florida Reef Tract (FRT) extends from the tropical Caribbean up the southeast coast of Florida into a temperate environment where tropical reef assemblages diminish with increasing latitude. This study used data from a three-year comprehensive fishery-independent survey to quantify reef fish spatial distribution along the Southeast FRT and define where the assemblage shifts from tropical to temperate. A total of 1,676 reef fish visual census samples were conducted to assess the populations on a stratified-random selection of sites of marine hardbottom habitats between the Miami River and St. Lucie inlet. Multivariate analyses were used to investigate differences in assemblages …


Occupancy Rates And Detection Probabilities Of Red-Backed Salamanders On The Virginia Fall Line, Jay D. McGhee 2016 Northwest Missouri State University

Occupancy Rates And Detection Probabilities Of Red-Backed Salamanders On The Virginia Fall Line, Jay D. Mcghee

Virginia Journal of Science

To meet the conservation needs of declining amphibian populations, there is a need to assess monitoring techniques in various habitat types and seasons. I assessed detection rates and proportion of area occupied via transect monitoring for red-backed salamanders at a site along the Virginia Fall Line in Doswell, Virginia. I established 24 transects in a 3.2-ha area in both riparian and upland habitats. Objects providing natural cover along these transects were sampled 3 times a week in fall and spring over a two-year period. Models of occupancy and detection were developed and compared using Akaike’s Information Criterion. Based on 113 …


Diversity-Dependent Cladogenesis Throughout Western Mexico: Evolutionary Biogeography Of Rattlesnakes (Viperidae: Crotalinae: Crotalus And Sistrurus), Christopher Blair, Santiago Sánchez-Ramírez 2016 CUNY New York City College of Technology

Diversity-Dependent Cladogenesis Throughout Western Mexico: Evolutionary Biogeography Of Rattlesnakes (Viperidae: Crotalinae: Crotalus And Sistrurus), Christopher Blair, Santiago Sánchez-Ramírez

Publications and Research

Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the …


Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff Lemen, Patricia Freeman 2016 University of Nebraska at Omaha

Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff Lemen, Patricia Freeman

School of Natural Resources: Faculty Publications

ABSTRACT.—Before white-nose syndrome arrives in Nebraska, it is important to document the preexposure distributions of cave bats in the state. We examined the distributions of Myotis lucifugus (little brown myotis), Myotis septentrionalis (northern long-eared myotis), and Perimyotis subflavus (tri-colored bat) in eastern Nebraska by setting acoustic detectors for a single night at 105 sites in wooded habitats during summers of 2012 and 2014. We compared 2 methods of determining presence at each site. Results of our analyses are fine-scale distributional maps for these bats and some range extensions from published records. Results for M. septentrionalis and P. subflavus are largely …


Effects Of Environmental Factors On The Abundance Of Blacklegged Ticks, Jasmine L. Miller, Roger A. LeBrun, Howard S. Ginsberg 2016 University of Rhode Island

Effects Of Environmental Factors On The Abundance Of Blacklegged Ticks, Jasmine L. Miller, Roger A. Lebrun, Howard S. Ginsberg

Senior Honors Projects

The nymphal stage of the blacklegged tick, Ixodes scapularis, is the major vector of Lyme disease, the most common vector-borne disease in North America. Tick abundance has generally been estimated using either flag/drag samples or samples from hosts. However, the biases of these sampling methods have not been adequately studied. We compared samples using both methods from sites in Massachusetts and Wisconsin. Tick abundance was compared with variables related to weather (temperature, relative humidity, and tick adverse moisture events), vegetation (canopy cover, tree density, shrub density, ground vegetation, and leaf litter cover), and host abundance (mice, small mammals, medium …


Avifaunal Community Composition In A Tropical Forest Corridor: A Case Study From The Atherton Tableland, North Queensland, Don Jones 2016 SIT Graduate Institute - Study Abroad

Avifaunal Community Composition In A Tropical Forest Corridor: A Case Study From The Atherton Tableland, North Queensland, Don Jones

Independent Study Project (ISP) Collection

Bird communities in tropical forest ecosystems are highly threatened by habitat loss and fragmentation. Replanted corridors connecting isolated forest remnants are a popular method of ameliorating certain negative impacts of habitat fragmentation. Such linkages can theoretically facilitate greater dispersal, increase gene flow, and reduce the risk of local extinctions in forest birds. However, relatively few studies have examined the utilization of reforested corridors by birds, and little hard data exists to support claims that this type of resource and time intensive project is the best use of often scarce funding for conservation. This study examined the avifaunal community present in …


Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger III, Michiko A. Squires, Louis A. Somma 2016 Fort Lauderdale Research and Education Center, University of Florida,

Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger Iii, Michiko A. Squires, Louis A. Somma

Papers in Herpetology

The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth. Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established. Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa, suggesting …


Surveys For The Alabama Map Turtle (Graptemys Pulchra) In The Coosa River, Georgia, John B. Jensen 2016 Georgia Department of Natural Resources

Surveys For The Alabama Map Turtle (Graptemys Pulchra) In The Coosa River, Georgia, John B. Jensen

Georgia Journal of Science

The Alabama Map Turtle, found only in Mobile Bay drainages, is state-listed in Georgia as “rare” and has been petitioned for federal listing as “threatened.” Because this species has been poorly studied in Georgia and in the Coosa River especially, a survey was undertaken to determine its status in the Coosa to help inform the federal listing decision. The 2014-2015 survey involved counting basking turtles from a motorboat with the aid of binoculars. The Alabama Map Turtle was the third most abundantly observed turtle species during the survey, preceded by only the Slider and River Cooter. All size/age classes were …


Variations In The Invertebrate Communities Of Wild Cape Cod Cranberry Bogs, Barbara Wagner 2016 University of Massachusetts Amherst

Variations In The Invertebrate Communities Of Wild Cape Cod Cranberry Bogs, Barbara Wagner

Masters Theses

As a species domesticated only in the last century, agricultural cranberry plants (Vaccinium macrocarpon) remain little removed from their wild relatives. Thus, it is a potential model species for studies of the earliest stages of domestication; however, there is little available quantitative information on its wild population biology and ecology. As such information is vital to studies of the ecological changes occurring during domestication, the purpose of this study was to consolidate the relevant knowledge available and conduct a preliminary search for patterns in the invertebrate communities of wild bogs. The alpha diversity was found to be greater …


Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson 2016 University of Massachusetts Amherst

Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson

Masters Theses

Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite …


Declining Frequency Of Road-Killed Rabbits In Central Georgia, Anna M. Bosch, Katelyn J. Benson, Alfred J. Mead 2016 Georgia College and State Univeristy

Declining Frequency Of Road-Killed Rabbits In Central Georgia, Anna M. Bosch, Katelyn J. Benson, Alfred J. Mead

Georgia Journal of Science

Cottontail rabbits (Sylvilagus floridanus, Sylvilagus aquaticus, Sylvilagus palustris) are a common component of the mammal fauna of the southeastern United States, yet their numbers have been in decline for at least the past 40 years. Urban sprawl, land use changes, forest maturation, and increased predation have contributed to the decline in Georgia. In the current study we explore the proposition that long-term changes in roadkill frequency track changes in wildlife populations as a whole. Using comparisons of historical data collected by Georgia Department of Natural Resources personnel and recent roadkill census data from Baldwin County, it appears that the overall …


Population Genetic Divergence Of Isle Royale Pearl Dace, Margarita Margariscus (Cyprinidae)., John F. Elder Jr., Jack R. Martin, Isaac J. Schlosser, Larry Kallemeyn 2016 Valdosta State University

Population Genetic Divergence Of Isle Royale Pearl Dace, Margarita Margariscus (Cyprinidae)., John F. Elder Jr., Jack R. Martin, Isaac J. Schlosser, Larry Kallemeyn

Georgia Journal of Science

In 1949, Hubbs and Lagler described morphological variation among pearl dace (Margariscus margarita) of inland lakes on Isle Royale, Michigan. For Harvey Lake, Hubbs and Lagler, proposed that pearl dace were sufficiently morphologically distinct to warrant subspecific status. They argued that divergence of the Harvey Lake pearl dace was due to allopatric differentiation in isolation from lower elevation lakes. Harvey Lake has been isolated by elevation from lower elevation lakes for approximately 10 to 15 thousand years. No genetic studies have been done on Isle Royale pearl dace to evaluate this hypothesis to date. Here we report the analysis of …


Density And Abundance Of Secretive Marsh Birds In Iowa, Tyler Harms, Stephen Dinsmore 2016 Iowa State University

Density And Abundance Of Secretive Marsh Birds In Iowa, Tyler Harms, Stephen Dinsmore

Tyler Harms

A decrease in wetland habitats throughout North America has caused a decline in populations of marsh birds. The objective of this study was to estimate population densities and abundances of secretive marsh birds in Iowa. Call-broadcast surveys were conducted in conjunction with distance sampling for eight species of marsh birds at wetlands in three regions of Iowa during 2009 and 2010. Regions were defined by observed microhabitat characteristics which also corresponded to physiographic regions. Region-specific density estimates were obtained using Program Distance for four species of marsh birds for which sufficient detections existed (Pied-billed Grebe [Podilymbus podiceps], Least …


Population Genetic Structure And Parasite Communities In A Nomadic Songbird, The Red Crossbill (Loxia Curvirostra), Erica L. Lovett 2016 The University of Western Ontario

Population Genetic Structure And Parasite Communities In A Nomadic Songbird, The Red Crossbill (Loxia Curvirostra), Erica L. Lovett

Electronic Thesis and Dissertation Repository

Although much speciation occurs in allopatry, populations with overlapping geographic ranges may also experience reduced gene flow due to ecological differences. Parasites are an important feature of the biotic environment, and place important selective pressures on their hosts, potentially reducing gene flow among geographically separated host populations. However, virtually nothing is known about host-parasite interactions in systems where hosts have nomadic distributions, and where ecologically distinct populations exist in sympatry. I examined population genetic structuring and characterized bloodborne parasite communities across four ecologically distinct, but partially sympatric, “vocal types” of nomadic red crossbills (Loxia curvirostra) sampled at multiple …


Swans: Their Biology And Natural History, Paul A. Johnsgard 2016 University of Nebraska-Lincoln

Swans: Their Biology And Natural History, Paul A. Johnsgard

Zea E-Books Collection

The seven species of swans of the world are an easily and universally recognized group of waterfowl, which have historically played important roles in the folklore, myths and legends in many of the world’s cultures. Among the largest of all flying birds, they have also almost universally been used as symbols of royalty, grace and beauty, and largely for these reasons swans have only rarely been considered acceptable as targets for sport hunting. Swans occur on all the continents except Africa, although most species are associated with the temperate and arctic zones of North America and Eurasia. Among birds, swans …


Phylogeography Of Two Species Of The Genus Apochthonius Chamberlin, 1929, In The Pacific Northwest (Arachnida, Pseudoscorpiones), Brandi Lynn Welch 2016 Portland State University

Phylogeography Of Two Species Of The Genus Apochthonius Chamberlin, 1929, In The Pacific Northwest (Arachnida, Pseudoscorpiones), Brandi Lynn Welch

Dissertations and Theses

I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic …


High Genetic Diversity But Low Population Structure In The Frog Pseudopaludicola Falcipes (Hensel, 1867) (Amphibia, Anura) From The Pampas Of South America, José A. Langone, Arley Camargo, Rafael O. de Sá 2016 University of Richmond

High Genetic Diversity But Low Population Structure In The Frog Pseudopaludicola Falcipes (Hensel, 1867) (Amphibia, Anura) From The Pampas Of South America, José A. Langone, Arley Camargo, Rafael O. De Sá

Biology Faculty Publications

Relative to South America’s ecoregions, the temperate grasslands of the Pampas have been poorly studied from a phylogeographic perspective. Based on an intermediate biogeographic setting between subtropical forest (Atlantic Forest) and arid ecosystems (Chaco and Patagonia), Pampean species are expected to show unstable demographic histories due to the Quaternary climatic oscillations. Herein, we investigate the phylogenetic relatedness and phylogeographic history of Pseudopaludicola falcipes, a small and common frog that is widely distributed across the Pampean grasslands. First, we use molecular data to assess if P. falcipes represents a single or multiple, separately evolving cryptic lineages. Because P. falcipes is …


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