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Articles 2401 - 2430 of 3773

Full-Text Articles in Population Biology

Status Of The State-Endangered Mussel, Ligumia Nasuta, In The Upper Cuyahoga River, Rachel E. Andrikanich, Stephanie A. Sredniawa Sep 2012

Status Of The State-Endangered Mussel, Ligumia Nasuta, In The Upper Cuyahoga River, Rachel E. Andrikanich, Stephanie A. Sredniawa

Undergraduate Research Posters 2012

The primary objective of our research was to assess population size and range of Ligumia nasuta, the Eastern Pond mussel in the Cuyahoga River watershed. We conclude that the Eastern Pond mussel may be all but gone from the East Branch and West Branch Cuyahoga Rivers, but may persist in better numbers in Portage County. Further studies are required before the sustainability of this species can be fully assessed.


A Tale Of Two Haplotypes: The Eda2r/Ar Intergenic Region Is The Most Divergent Genomic Segment Between Africans And East Asians In The Human Genome, Amanda M. Casto, Brenna M. Henn, Jeffery M. Kidd, Carlos D. Bustamante, Marcus W. Feldman Sep 2012

A Tale Of Two Haplotypes: The Eda2r/Ar Intergenic Region Is The Most Divergent Genomic Segment Between Africans And East Asians In The Human Genome, Amanda M. Casto, Brenna M. Henn, Jeffery M. Kidd, Carlos D. Bustamante, Marcus W. Feldman

Human Biology Open Access Pre-Prints

Single nucleotide polymorphisms (SNPs) with large allele frequency differences between human populations are relatively rare. The longest run of SNPs with an allele frequency difference of one between the Yoruba of Nigeria and the Han Chinese is found on the long arm of the X chromosome in the intergenic region separating the EDA2R and AR genes. It has been proposed that the unusual allele frequency distributions of these SNPs are the result of a selective sweep affecting African populations that occurred after the Out-of-Africa migration. To investigate the evolutionary history of the EDA2R/AR intergenic region, we characterized the haplotype structure …


Plains Harvest Mouse (Reithrodontomys Montanus Griseus): Species Conservation Assessment, Melissa J. Panella Sep 2012

Plains Harvest Mouse (Reithrodontomys Montanus Griseus): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding species of interest. The Nebraska Natural Legacy Project recognizes the plains harvest mouse (Reithrodontomys montanus griseus) as a Tier I at-risk species of high conservation need. Some general management recommendations are made here regarding the plains harvest mouse; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge of the plains harvest mouse …


Topeka Shiner (Notropis Topeka): Species Conservation Assessment, Melissa J. Panella Sep 2012

Topeka Shiner (Notropis Topeka): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the Topeka shiner (Notropis topeka) as a Tier I at-risk species of high priority for conservation. Some general management recommendations are made here regarding Topeka shiners; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge of the Topeka shiner that …


High Prevalence Of The Amphibian Chytrid Fungus (Batrachochytrium Dendrobatidis) Across Multiple Taxa And Localities In The Highlands Of Ethiopia, David J. Gower, Thomas M. Doherty-Bone, Roman K. Aberra, Abebe Mengistu, Silvia Schwaller, Michele Menegon, Rafael O. De Sá, Samy A. Saber, Andrew A. Cunningham, Simon P. Loader Sep 2012

High Prevalence Of The Amphibian Chytrid Fungus (Batrachochytrium Dendrobatidis) Across Multiple Taxa And Localities In The Highlands Of Ethiopia, David J. Gower, Thomas M. Doherty-Bone, Roman K. Aberra, Abebe Mengistu, Silvia Schwaller, Michele Menegon, Rafael O. De Sá, Samy A. Saber, Andrew A. Cunningham, Simon P. Loader

Biology Faculty Publications

Surveys of the potentially lethal amphibian chytrid fungus (Batrachochytrium dendrobatidis - Bd) in Africa are patchy, especially in some regions of high species endemicity. We present results of the first Bd surveys of wild amphibians in Ethiopia, for two upland regions on either side of the Rift Valley: the Bale Mountains and the Kaffa region. Surveys were opportunistic so that robust interpretation of the data is limited. Utilizing diagnostic qPCR assays, 51 out of 120 frogs (14 species in 10 genera) tested positive for Bd at altitudes of 1,620–3,225 m, across all genera and species, and all but …


The Development Of Dermatonotus Muelleri (Anura: Microhylidae: Gastrophryninae), Marissa Fabrezi, Silvia Quinzio, Javier Goldberg, Rafael O. De Sá Sep 2012

The Development Of Dermatonotus Muelleri (Anura: Microhylidae: Gastrophryninae), Marissa Fabrezi, Silvia Quinzio, Javier Goldberg, Rafael O. De Sá

Biology Faculty Publications

The monophyly of Microhylidae is supported by an overwhelming accumulation of synapomorphic larval features. Despite the distinctiveness of the microhylid tadpole, few studies have focused on larval development. Microhylid larval morphology is usually described and based on standard tables that imply that developmental events at equivalent stages of overall tadpole development are independent from species-specific patterns of developmental timing. Herein, we present additional developmental data based on external morphology and field data on larval growth for the gastrophrynine microhylid Dermatonotus muelleri. We describe internal morphological variation (e.g., skeletal and soft systems) during larval development. The results indicate that the onset …


Comparative Phylogeography Of Central African Duikers Using Non-Invasive Sampling Methods, Stephan Ntie Aug 2012

Comparative Phylogeography Of Central African Duikers Using Non-Invasive Sampling Methods, Stephan Ntie

LSU New Orleans Theses and Dissertations

The present study sets out to assess patterns of evolutionary diversification in central African duikers (subfamily Cephalophinae). The sampling strategy consisted of collecting geo-referenced duiker feces across 43 sites and seven countries. However, several challenges related to the use of non-invasive samples needed to be addressed prior to large scale DNA amplification. First, the best storage method for obtaining DNA from fecal samples needed to be established. Our study revealed that while silica is best for nuclear microsatellite analyses, RNAlater is the best storage medium for maximal mitochondrial amplification. Moreover, extracting DNA as early as possible always provided the …


A Genetic Survey Of English Sole Populations In The Salish Sea, Elizabeth S. Gutierrez, Gary A. Winans, Jon Baker, Amanda Cope Aug 2012

A Genetic Survey Of English Sole Populations In The Salish Sea, Elizabeth S. Gutierrez, Gary A. Winans, Jon Baker, Amanda Cope

STAR Program Research Presentations

This summer I interned at the Northwest Fisheries Science Center in Seattle, WA and participated in NOAA’s Salish Sea Project. The Salish Sea Project’s goal is to identify genetically distinctive groups of species in the Salish Sea that may have unique evolutionary and/or adaptive backgrounds. These findings will allow NOAA to promote and monitor the natural production of species in the Salish Sea, to select representative populations for experimental work regarding pollution, ocean acidification and climate change, to contribute to managing the ecosystem for intra- and inter-species diversity, and to help make informed decisions about adaptive management and marine protected …


Developing Monitoring Methods For Leptasterias Spp. As Sentinel Species In Detecting Local Environmental Changes, Zachary Sturbaum, Kathryn Nuessly, Riley J. Smith, C. Sarah Cohen Aug 2012

Developing Monitoring Methods For Leptasterias Spp. As Sentinel Species In Detecting Local Environmental Changes, Zachary Sturbaum, Kathryn Nuessly, Riley J. Smith, C. Sarah Cohen

STAR Program Research Presentations

Leptasterias spp., a six-rayed sea star, is found in rocky intertidal habitats ranging from Alaska to central California. Leptasterias spp. can be monitored on a broad scale throughout their range by a variety of means using timed counts and random plot censusing in order to detect both large-scale and local-level changes in the environment due to climate change, land-based human activity, or other environmental events. Leptasterias brood their young externally until the embryos grow into fully developed juveniles. These juveniles disperse by crawling away, limiting their dispersal potential. This localized dispersal provides an opportunity to use Leptasterias spp …


Greater Galagos Near Mt. Kasigau, Kenya: Population Density Estimates, Andrea Falcetto Aug 2012

Greater Galagos Near Mt. Kasigau, Kenya: Population Density Estimates, Andrea Falcetto

Masters Theses & Specialist Projects

This study examined population density and habitat use of a species of greater galago, genus Otolemur, around Mt. Kasigau, Kenya. Mt. Kasigau has a unique regional microclimate, a cloud forest, which provides many different flora and fauna a home. To examine population density, two different methods were used. The first method was using line transects and analyzing results using Distance 6.0. These surveys were conducted during both dry and wet season and results were compared after the study. The second method was to trap individuals and use mark-recapture to determine population density. When caught in a trap, individuals were …


Evaluation Of The Effects Of September Hunting Seasons On Canada Geese In Nebraska, Scott R. Groepper, Mark P. Vrtiska, Larkin A. Powell, Scott E. Hygnstrom Aug 2012

Evaluation Of The Effects Of September Hunting Seasons On Canada Geese In Nebraska, Scott R. Groepper, Mark P. Vrtiska, Larkin A. Powell, Scott E. Hygnstrom

School of Natural Resources: Faculty Publications

Populations of temperate-nesting Canada geese (Branta canadensis) have increased in Nebraska, USA, resulting in an increased number of nuisance and damage complaints. September hunting seasons were initiated in southeastern Nebraska in 2004 to reduce populations of Canada geese. We analyzed band recoveries from Canada geese banded in southeastern Nebraska during their hatch-year (HY) or after-hatch-year (AHY) to determine whether September hunting seasons affected survival, harvest, and recovery rates. Survival analyses revealed that HY geese had higher survival than AHY geese (SAHY = 0.696, 95% CI = 0.679–0.713; SHY = 0.896, 95% CI = 0.786–0.953) and September seasons did …


The Breeding Biology Of The Northern Pygmy Owl: Do The Smallest Of The Small Have An Advantage?, John F. Deshler, Michael T. Murphy Aug 2012

The Breeding Biology Of The Northern Pygmy Owl: Do The Smallest Of The Small Have An Advantage?, John F. Deshler, Michael T. Murphy

Biology Faculty Publications and Presentations

We explored the breeding biology of the Northern Pygmy-Owl (Glaucidium gnoma) from 2007 to 2009 in a forested reserve in Portland, Oregon. Large body size is often assumed to give animals reproductive advantages, and we tested whether body size affected timing of breeding and examined variation in diet, breeding date, clutch size, and reproductive success to explore whether the presumed benefits of large body size are evident in this species. The average size of 13 clutches was 5.8, and nest success was high (92%); 22 successful nests fledged an average of 5.2 young. Dates of first laying varied …


Modeling And Mathematical Analysis Of Plant Models In Ecology, Eric A. Eager Aug 2012

Modeling And Mathematical Analysis Of Plant Models In Ecology, Eric A. Eager

Department of Mathematics: Dissertations, Theses, and Student Research

Population dynamics tries to explain in a simple mechanistic way the variations of the size and structure of biological populations. In this dissertation we use mathematical modeling and analysis to study the various aspects of the dynamics of plant populations and their seed banks.

In Chapter 2 we investigate the impact of structural model uncertainty by considering different nonlinear recruitment functions in an integral projection model for Cirsium canescens. We show that, while having identical equilibrium populations, these two models can elicit drastically different transient dynamics. We then derive a formula for the sensitivity of the equilibrium population to …


Scorpion Phylogeography In The North American Aridlands, Matthew Ryan Graham Aug 2012

Scorpion Phylogeography In The North American Aridlands, Matthew Ryan Graham

UNLV Theses, Dissertations, Professional Papers, and Capstones

Understanding the geographic, geologic, and climatic forces responsible for generating current patterns of biodiversity has been a central objective of phylogeography. To develop a better understanding of these processes in the North American arid lands, I used DNA sequence data and species distribution modeling to conduct three phylogeographic assessments incorporating four species of arid-adapted scorpions:Hadrurus arizonensis, H. jedediah, H. spadix,and Paruroctonus becki. In an assessment of H. arizonensis, phylogeographic patterns indicate that Pleistocene climate cycles and associated glacial refugia played a central role in structuring the genetic diversity of this species in the Mojave and Sonoran deserts, mostly supporting predictions …


The Spatial Signature Of Biotic Interactions Of A Clonal And A Non-Clonal Palmetto In A Subtropical Plant Community, Mizuki Takahashi, Toshiro Kubota, Liana M. Horner, Nathan A. Keller, Warren G. Abrahamson Ii Jul 2012

The Spatial Signature Of Biotic Interactions Of A Clonal And A Non-Clonal Palmetto In A Subtropical Plant Community, Mizuki Takahashi, Toshiro Kubota, Liana M. Horner, Nathan A. Keller, Warren G. Abrahamson Ii

Faculty Journal Articles

Spatial analyses of plant-distribution patterns can provide inferences about intra- and interspecific biotic interactions. Yet, such analyses are rare for clonal plants because effective tools (i.e., molecular markers) needed to map naturally occurring clonal individuals have only become available recently. Clonal plants are unique in that a single genotype has a potential to spatially place new individuals (i.e., ramets) in response to intra- and interspecific biotic interactions. Laboratory and greenhouse studies suggest that some clonal plants can avoid intra-genet, inter-genet, and inter-specific competition via rootplacement patterns. An intriguing and yet to be explored question is whether a spatial signature of …


Estimating The Potential Impacts Of Large Mesopredators On Benthic Resources: Integrative Assessment Of Spotted Eagle Ray Foraging Ecology In Bermuda, Matthew J. Ajemian, Sean P. Powers, Thaddeus J. T. Murdoch Jul 2012

Estimating The Potential Impacts Of Large Mesopredators On Benthic Resources: Integrative Assessment Of Spotted Eagle Ray Foraging Ecology In Bermuda, Matthew J. Ajemian, Sean P. Powers, Thaddeus J. T. Murdoch

University Faculty and Staff Publications

Declines of large sharks and subsequent release of elasmobranch mesopredators (smaller sharks and rays) may pose problems for marine fisheries management as some mesopredators consume exploitable shellfish species. The spotted eagle ray (Aetobatus narinari) is the most abundant inshore elasmobranch in subtropical Bermuda, but its predatory role remains unexamined despite suspected abundance increases and its hypothesized specialization for mollusks. We utilized a combination of acoustic telemetry, benthic invertebrate sampling, gut content analysis and manipulative experiments to assess the impact of spotted eagle rays on Bermudian shellfish resources. Residency and distribution of adult spotted eagle rays was monitored over …


Draft Management Plan For The West Coast Rock Lobster Managed Fishery., Department Of Fisheries Western Australia Jul 2012

Draft Management Plan For The West Coast Rock Lobster Managed Fishery., Department Of Fisheries Western Australia

Fisheries Management Papers

West Coast Rock Lobster Managed Fishery licensees target the western rock lobster, Panulirus Cygnus using baited pots (traps) on the west coast of Western Australia (WA). The fishery, which has long been one of the most valuable single species fisheries in Australia, extends from North West Cape to Cape Leeuwin in the south, with the main fishing occurring between Shark Bay and Perth.

In response to a series of poor puerulus settlements commencing in 2009, a suite of management changes have been introduced to significantly reduce catch levels to appropriately deal with the expected low levels of recruitment entering the …


Review Of Report On The “Biology And Stock Status Of Demersal Scalefish Indicator Species In The Gascoyne Coast Bioregion", Department Of Fisheries Jul 2012

Review Of Report On The “Biology And Stock Status Of Demersal Scalefish Indicator Species In The Gascoyne Coast Bioregion", Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.


Fecal Near Infrared Spectroscopy To Discriminate Physiological Status In Giant Pandas., Erin E. Wiedower, Andrew J. Kouba, Carrie K. Vance, Rachel L. Hansen, Jerry W. Stuth, Douglas R. Tolleson Jun 2012

Fecal Near Infrared Spectroscopy To Discriminate Physiological Status In Giant Pandas., Erin E. Wiedower, Andrew J. Kouba, Carrie K. Vance, Rachel L. Hansen, Jerry W. Stuth, Douglas R. Tolleson

CALS Publications

Giant panda (Ailuropoda melanoleuca) monitoring and research often require accurate estimates of population size and density. However, obtaining these estimates has been challenging. Innovative technologies, such as fecal near infrared reflectance spectroscopy (FNIRS), may be used to differentiate between sex, age class, and reproductive status as has been shown for several other species. The objective of this study was to determine if FNIRS could be similarly used for giant panda physiological discriminations. Based on samples from captive animals in four U.S. zoos, FNIRS calibrations correctly identified 78% of samples from adult males, 81% from adult females, 85% from adults, 89% …


Policy On Habitat Enhancement Structures In Western Australia, Department Of Fisheries Western Australia. Jun 2012

Policy On Habitat Enhancement Structures In Western Australia, Department Of Fisheries Western Australia.

Fisheries Management Papers

Habitat enhancement structures range widely in design. They generally aim to enhance fish habitat by providing a structure for fish and other aquatic life to colonise and potentially lead to an increase in their biological production.

The primary function of an artificial reef is to provide additional structure and habitat to support an increased production of fish ad other aquatic organisms.


The Dynamics Of Location: Influence Of Predation By Chaoborus Larvae On Rotifer Diel Vertical Migration Patterns, Kristina P. Riemer May 2012

The Dynamics Of Location: Influence Of Predation By Chaoborus Larvae On Rotifer Diel Vertical Migration Patterns, Kristina P. Riemer

Lawrence University Honors Projects

The locations of freshwater organisms in lakes are determined by the convergence of many competing factors. While predation pressure is one of these, also important are areas of food concentration and the physical and chemical constraints of a system. Diel vertical migration is a behavior exhibited by freshwater organisms in many taxa that is the result of balancing these factors. Diel vertical migration consists of movement by these organisms throughout the water column in accordance with a 24 hour cycle. This oscillation is generally driven by the competing factors of predation pressure and food acquisition, and is modified by physical …


Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich May 2012

Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich

Lawrence University Honors Projects

Historical records from Lake Winnebago show minimal macrophyte growth; however, reports from recent years claim that macrophyte growth in some areas of the lake has reached nuisance levels. This study aimed to investigate the species of macrophytes present and their abundances in four near-shore locations, as well as measurements of multiple water quality conditions. Rake sampling was used to identify species and quantify their abundances and distributions. In addition, data were collected on light penetration, Secchi depths, and suspended algae chlorophyll concentrations at each site. These data from shallow near-shore sites reveal trends in changing water clarity and light penetration …


Will Extreme Climatic Events Facilitate Biological Invasions?, Jeffrey M. Diez, Carla M. D'Antonio, Jeffrey S. Dukes, Edwin D. Grosholz, Julian D. Olden, Cascade J.B. Sorte, Dana M. Blumenthal, Bethany A. Bradley, Regan I. Early, Inés Ibáñez, Sierra J. Jones, Joshua J. Lawler, Luke P. Miller May 2012

Will Extreme Climatic Events Facilitate Biological Invasions?, Jeffrey M. Diez, Carla M. D'Antonio, Jeffrey S. Dukes, Edwin D. Grosholz, Julian D. Olden, Cascade J.B. Sorte, Dana M. Blumenthal, Bethany A. Bradley, Regan I. Early, Inés Ibáñez, Sierra J. Jones, Joshua J. Lawler, Luke P. Miller

Faculty Publications, Biological Sciences

Extreme climatic events (ECEs) – such as unusual heat waves, hurricanes, floods, and droughts – can dramatically affect ecological and evolutionary processes, and these events are projected to become more frequent and more intense with ongoing climate change. However, the implications of ECEs for biological invasions remain poorly understood. Using concepts and empirical evidence from invasion ecology, we identify mechanisms by which ECEs may influence the invasion process, from initial introduction through establishment and spread. We summarize how ECEs can enhance invasions by promoting the transport of propagules into new regions, by decreasing the resistance of native communities to establishment, …


An Approach For Use Of Dual Frequency Identification Sonar (Didson) To Quantify Behavioral Aspects Of Piscivory At Ecologically Relevant Time And Space Scales, Victoria E. Price May 2012

An Approach For Use Of Dual Frequency Identification Sonar (Didson) To Quantify Behavioral Aspects Of Piscivory At Ecologically Relevant Time And Space Scales, Victoria E. Price

Master's Theses

Predator-prey interactions of large vagile fishes are difficult to study in the ocean due to limitations in the space and time requirements for observations. Small-scale direct underwater observations by divers (<10m >radius) and large-scale hydroacoustic surveys (10s - 100s km2) are traditional approaches. However, large piscivorous predators identify and attack prey at the scale of meters to tens of meters. Dual- Frequency Identification Sonar, or DIDSON, is a high-resolution acoustic camera operating in the MHz range that provides detailed continuous video-like imaging of objects out to 30 m range. This technology can be used to observe predator-prey interactions at ecologically …


Terrestrial Habitat Requirements Of Nesting Freshwater Turtles, D. A. Steen, J. P. Gibbs, K. A. Buhlman, J. L. Carr, B. W. Compton, J. D. Congdon, J. S. Doody, J. C. Godwin, Kerry L. Holcomb, D. R. Jackson, F. J. Janzen, G. Johnson, M. T. Jones, J. T. Lamer, T. A. Langen, M. V. Plummer, J. W. Rowe, R. A. Saumure, J. K. Tucker, D. S. Wilson May 2012

Terrestrial Habitat Requirements Of Nesting Freshwater Turtles, D. A. Steen, J. P. Gibbs, K. A. Buhlman, J. L. Carr, B. W. Compton, J. D. Congdon, J. S. Doody, J. C. Godwin, Kerry L. Holcomb, D. R. Jackson, F. J. Janzen, G. Johnson, M. T. Jones, J. T. Lamer, T. A. Langen, M. V. Plummer, J. W. Rowe, R. A. Saumure, J. K. Tucker, D. S. Wilson

All Faculty Scholarship for the College of the Sciences

Because particular life history traits affect species vulnerability to development pressures, cross-species summaries of life history traits are useful for generating management guidelines. Conservation of aquatic turtles, many members of which are regionally or globally imperiled, requires knowing the extent of upland habitat used for nesting. Therefore, we compiled distances that nests and gravid females had been observed from wetlands. Based on records of > 8000 nests and gravid female records compiled for 31 species in the United States and Canada, the distances that encompass 95% of nests vary dramatically among genera and populations, from just 8 m for Malaclemys to …


Productivity And Habitat Features Of Swainson's Hawks (Buteo Swainsoni) Nesting In Suburban And Agricultural Areas Of Southwest Idaho, Steven Edward Alsup May 2012

Productivity And Habitat Features Of Swainson's Hawks (Buteo Swainsoni) Nesting In Suburban And Agricultural Areas Of Southwest Idaho, Steven Edward Alsup

Boise State University Theses and Dissertations

I compared nesting success and productivity of Swainson’s Hawks nesting in suburban and agricultural areas in southwest Idaho to assess the effects of land use change on Swainson’s Hawk reproduction. I also evaluated habitat parameters and land use patterns around nesting areas to determine if nest site, habitat, and/or landscape features were related to reproductive success in Swainson’s Hawks. I recorded habitat characteristics, nest tree characteristics, distances to four habitat features, and disturbance types, as well as land use patterns within a 1500m radius around nest trees to assess any differences in nest site characteristics, habitat features, and/or landscape features …


Comparing Avian Diversity Between Perennial And Ephemeral Water Sources Located Within The Northern Chihuahuan Desert, Geoffrey H. Wiseman ^, Jerry D. Johnson, Vanessa L. Lougheed * Apr 2012

Comparing Avian Diversity Between Perennial And Ephemeral Water Sources Located Within The Northern Chihuahuan Desert, Geoffrey H. Wiseman ^, Jerry D. Johnson, Vanessa L. Lougheed *

COURI Symposium Abstracts, Spring 2012

Water availability in the Chihuahuan Desert is highly variable and dependent on various physical factors. Indio Mountains Research Station (IMRS), located in southeastern Hudspeth County, Texas, contains one perennial water source, Squaw Spring, and at least sixteen man-made ephemeral “tanks” previously used for watering livestock. It was hypothesized that bird diversity would be greater near Squaw Spring, due to continuous water availability, rather than ephemeral tanks where water availability is inconsistent.

The experimental design included a multi-seasonal bird survey by means of visual sightings of different species, backed by photographic evidence to assure accurate identification. Surveys were completed near Squaw …


How Roads Affect The Population Genetic Structure Of The Lizard Uta Stansburiana In The Northern Chihuahuan Desert, Priscilla D. Duran ^, Kevin W. Floyd, Elizabeth J. Walsh * Apr 2012

How Roads Affect The Population Genetic Structure Of The Lizard Uta Stansburiana In The Northern Chihuahuan Desert, Priscilla D. Duran ^, Kevin W. Floyd, Elizabeth J. Walsh *

COURI Symposium Abstracts, Spring 2012

Urbanization can have significant ecological effects on natural populations, including habitat fragmentation through increased road density. Roads may isolate populations, causing disruption of gene flow, inbreeding, and decreased genetic diversity. In this study we investigate how two roads, interstate highway I-10 and rural country road NM-9, affect population genetic structure of ideblotched lizards (Uta stansburiana) in the northern Chihuahuan Desert of New Mexico. Lizards were trapped on both sides of each road, plus one control site/road. Nine microsatellite loci were amplified to determine signatures of disrupted gene flow. Genotypes were obtained for 144 individuals from three sites, I-10 …


Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible Apr 2012

Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean …


Effects Of The Parasitic Dinoflagellate Hematodinium Sp. On Blue Crab (Callinectes Sapidus) Activity Predation And Habitat Selection, John M. Tiggelaar Ii Apr 2012

Effects Of The Parasitic Dinoflagellate Hematodinium Sp. On Blue Crab (Callinectes Sapidus) Activity Predation And Habitat Selection, John M. Tiggelaar Ii

Biological Sciences Theses & Dissertations

The blue crab Callinectes sapidus occurs along the Atlantic and Gulf coasts of the United States, and in high salinity regions, they are subject to lethal infection by the parasitic dinoflagellate Hematodinium. In Virginia's seaside estuaries, the prevalence of Hematodinium infection of C. sapidus can sometimes exceed 50%, threatening the commercial fishery for this species. Indeed, other commercially important crustacean fisheries have approached collapse due to Hematodinium infections. Most studies of this host-parasite interaction have focused on epidemiology, host-pathogen dynamics, and pathogen transmission, and little is known about the impact of the parasite on host behavior and population dynamics. …