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2013

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Articles 1 - 30 of 68

Full-Text Articles in Population Biology

Photo-Identification Methods Reveal Seasonal And Long-Term Site-Fidelity Of Risso’S Dolphins (Grampus Griseus) In Shallow Waters (Cardigan Bay, Wales), Marijke N. De Boer, Josephine Clark, Mardik F. Leopold, Mark P. Simmonds, Peter J.H. Reijnders Dec 2013

Photo-Identification Methods Reveal Seasonal And Long-Term Site-Fidelity Of Risso’S Dolphins (Grampus Griseus) In Shallow Waters (Cardigan Bay, Wales), Marijke N. De Boer, Josephine Clark, Mardik F. Leopold, Mark P. Simmonds, Peter J.H. Reijnders

Ecology Collection

A photo-identification study on Risso’s dolphins was carried out off Bardsey Island in Wales (July to September, 1997-2007). Their local abundance was estimated using two different analytical techniques: 1) mark-recapture of well-marked dolphins using a “closed-population” model; and 2) a census technique based on the total number of iden-tified individual dolphins sighted over the study period. The mark-recapture estimates of 121 (left sides; 64 - 178, 95% CI; CV 0.24) and 145 dolphins (right sides; 78 - 213, 95% CI; CV 0.24) closely matched the census technique estimates (population size of 90 - 151). It was found that the dolphins …


Census And Mapping Of Chorro Creek Bog Thistle In Reservoir Canyon, San Luis Obispo, Ca, Tyler Michael Lutz Dec 2013

Census And Mapping Of Chorro Creek Bog Thistle In Reservoir Canyon, San Luis Obispo, Ca, Tyler Michael Lutz

Biological Sciences

Chorro Creek bog thistle (Cirsium fontinale var. obispoense) is a federally endangered variety of Fountain thistle endemic to western San Luis Obispo County. The U.S. Fish and Wildlife Service knows of nineteen populations, many with multiple colonies. A population was discovered in the Reservoir Canyon Natural Reserve in 2001, but has not been monitored or described since the time of its discovery. In fall of 2013, a census of the population was performed, the four colonies were mapped, and a floristic survey was conducted. A field experiment was initiated to determine if reducing the riparian canopy coverage can …


A Seasonal, Density-Dependent Model For The Management Of An Invasive Weed, Esther Shyu, Eleanor A. Pardini, Tiffany M. Knight, Hal Caswell Dec 2013

A Seasonal, Density-Dependent Model For The Management Of An Invasive Weed, Esther Shyu, Eleanor A. Pardini, Tiffany M. Knight, Hal Caswell

Biology Faculty Research

The population effects of harvest depend on complex interactions between density dependence, seasonality, stage structure, and management timing. Here we present a periodic nonlinear matrix population model that incorporates seasonal density dependence with stage-selective and seasonally selective harvest. To this model, we apply newly developed perturbation analyses to determine how population densities respond to changes in harvest and demographic parameters. We use the model to examine the effects of popular control strategies and demographic perturbations on the invasive weed garlic mustard (Alliaria petiolata). We find that seasonality is a major factor in harvest outcomes, because population dynamics may …


A Population Model For Walleye In Nebraska Irrigation Reservoirs, Robert A. Kill Dec 2013

A Population Model For Walleye In Nebraska Irrigation Reservoirs, Robert A. Kill

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding how and why fish population size changes between years is a central theme in fisheries ecology. Fishery agencies have limited time and financial resources, thus there is a need for a quantitative way to direct the limited time and financial resources so agencies can manage fisheries more efficiently. I developed a tool for fishery managers that synthesizes common population indices and evaluated the relative importance of those indices given varying uncertainty in age-0 walleye Sander vitreus survival. Under most circumstances, I determined that resources are best utilized in reducing age-0 survival uncertainty when understanding walleye population growth. I applied …


An Assessment Of Habitat Suitability For Pronghorn Populations Of The Central Valley Region Of California, Virginia Burroughs Dec 2013

An Assessment Of Habitat Suitability For Pronghorn Populations Of The Central Valley Region Of California, Virginia Burroughs

Master's Theses

Efforts to reintroduce and maintain populations of pronghorn (Antilocapra americana) to the California Central Valley, specifically the Carrizo Plain National Monument (CPNM) and the Mojave Desert (Antelope Valley) portion of Tejon Ranch, have largely been unsuccessful due to dwindling numbers of translocated animals. The objective of this study was to improve upon previous models for the CPNM using aerial survey data and then apply the model to the Tejon Ranch. Aerial survey data collected from 2000-2010 on the CPNM was used to establish “use” and “non-use” areas in the model. Model variables included vegetation type (forest, shrub, grassland, …


Confronting Uncertainty In Wildlife Management: Performance Of Grizzly Bear Management, Kyle A. Artelle, Sean C. Anderson, Andrew B. Cooper, Paul C. Paquet, John D. Reynolds, Chris T. Darimont Nov 2013

Confronting Uncertainty In Wildlife Management: Performance Of Grizzly Bear Management, Kyle A. Artelle, Sean C. Anderson, Andrew B. Cooper, Paul C. Paquet, John D. Reynolds, Chris T. Darimont

Wildlife Population Management Collection

Scientific management of wildlife requires confronting the complexities of natural and social systems. Uncertainty poses a central problem. Whereas the importance of considering uncertainty has been widely discussed, studies of the effects of unaddressed uncertainty on real management systems have been rare. We examined the effects of outcome uncertainty and components of biological uncertainty on hunt management performance, illustrated with grizzly bears (Ursus arctos horribilis) in British Columbia, Canada. We found that both forms of uncertainty can have serious impacts on management performance. Outcome uncertainty alone – discrepancy between expected and realized mortality levels – led to excess mortality in …


Bailey’S Eastern Woodrat (Neotoma Floridana Baileyi): Species Conservation Assessment, Melissa J. Panella Nov 2013

Bailey’S Eastern Woodrat (Neotoma Floridana Baileyi): 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 Bailey’s eastern woodrat (Neotama floridana baileyi) as a Tier I at-risk species. Provided are some general management recommendations regarding Bailey’s eastern woodrats. Conservation practitioners will need to use professional judgment for specific management decisions based on objectives, location, and site-specific conditions. This resource was designed to provide an overview of our current knowledge of Bailey’s eastern woodrats and may aid in …


Key Findings Of The 2013 West Coast Demersal Scalefish Resource Stock Assessment, Department Of Fisheries Western Australia Nov 2013

Key Findings Of The 2013 West Coast Demersal Scalefish Resource Stock Assessment, Department Of Fisheries Western Australia

Fisheries Management Papers

Now, six years since the first stock assessment, and with the completion of a comprehensive boat-based survey of recreational fishing, ongoing annual monitoring of commercial and charter catches and a third stock assessment completed in 2013, the effectiveness of current management measures is able to be assessed.

This paper also provides an overview of the determination in regard to the sectoral allocations of the demersal scalefish resource in the WCB.


The Cost Of Green Infrastructure: Worth The Investment?, Martha Sheils Nov 2013

The Cost Of Green Infrastructure: Worth The Investment?, Martha Sheils

Green Infrastructure

Is GI worth the investment?

• LID techniques often lead to cost savings when we look at WHOLE PROJECT COSTS

• Natural Infrastructure investments for flood control, drinking water protection and wildlife habitat can yield SIGNIFICANT AVOIDED COSTS and additional co-benefits to communitites


Western Burrowing Owl (Athene Cunicularia Hypugaea): Species Conservation Assessment, Melissa J. Panella Nov 2013

Western Burrowing Owl (Athene Cunicularia Hypugaea): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in the 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 western subspecies of Burrowing Owl (Athene cunicularia hypugaea) as a Tier I at-risk species. Provided are some general management recommendations regarding Western Burrowing Owls (hereafter Burrowing Owls). Conservation practitioners will need to use professional judgment for specific management decisions based on objectives, location, and site-specific conditions. Based on a considerable body of literature, this particular species conservation assessment provides an …


The Tadpole Of Leptodactylus Caatingae Heyer & Juncá, 2003 (Anura: Leptodactylidae): External Morphology, Internal Anatomy, And Natural History, Felipe De Madeiros Magalhães, Adrian Antonio Garda, Ralita Ferreira Amado, Rafael O. De Sá Nov 2013

The Tadpole Of Leptodactylus Caatingae Heyer & Juncá, 2003 (Anura: Leptodactylidae): External Morphology, Internal Anatomy, And Natural History, Felipe De Madeiros Magalhães, Adrian Antonio Garda, Ralita Ferreira Amado, Rafael O. De Sá

Biology Faculty Publications

We describe and illustrate the external morphology, oral disc, chondrocranium, and internal oral anatomy of Leptodactylus caatingae larvae. We analyze the internal oral anatomy using scanning electron microscopy of a larva in Gosner, stage 38 and chondrocranial anatomy is reported for Gosner stage 34. The tadpole at Gosner stage 38 has a globular body shape with low tail fins and a ventral oral disc bordered by two rows of marginal papillae on most of the disc, except for the anterior labium and a medial portion of the posterior labium where papillae are simple; a wide rostral gap is present, labial …


A Framework To Evaluate Wildlife Feeding In Research, Wildlife Management, Tourism And Recreation, Sara Dubois, David Fraser Oct 2013

A Framework To Evaluate Wildlife Feeding In Research, Wildlife Management, Tourism And Recreation, Sara Dubois, David Fraser

Wildlife Population Management Collection

Feeding of wildlife occurs in the context of research, wildlife management, tourism and in opportunistic ways. A review of examples shows that although feeding is often motivated by good intentions, it can lead to problems of public safety and conservation and be detrimental to the welfare of the animals. Examples from British Columbia illustrate the problems (nuisance animal activity, public safety risk) and consequences (culling, translocation) that often arise from uncontrolled feeding. Three features of wildlife feeding can be distinguished: the feasibility of control, the effects on conservation and the effects on animal welfare. An evaluative framework incorporating these three …


Growth Of Tropical Dasyatid Rays Estimated Using A Multi-Analytical Approach, Owen R. O'Shea, Matias Braccini, Rory Mcauley, Conrad W. Speed, Mark G. Meekan Oct 2013

Growth Of Tropical Dasyatid Rays Estimated Using A Multi-Analytical Approach, Owen R. O'Shea, Matias Braccini, Rory Mcauley, Conrad W. Speed, Mark G. Meekan

Fisheries Research Articles

We studied the age and growth of four sympatric stingrays: reticulate whipray, Himanutra uarnak (n=19); blue mask, Neotrygon kuhlii (n=34); cowtail, Pastinachus atrus (n=32) and blue-spotted fantail, Taeniura lymma (n=40) rays at Ningaloo Reef, a fringing coral reef on the north-western coast of western Australia. Age estimates derived from band counts within sectioned vertebrae ranged between 1 and 27 years (H. uarnak, 1 - 25 yrs.; N. kuhlii, 1.5 - 13 yrs.; P. atrus, 1 - 27 yrs. and T. lymma, 1 -11 yrs.). Due to limitations of sample sizes, we combined several analytical methods …


Fringed Myotis (Myotis Thysanodes Pahasapensis): Species Conservation Assessment, Melissa J. Panella Oct 2013

Fringed Myotis (Myotis Thysanodes Pahasapensis): 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 fringed myotis (Myotis thysanodes pahasapensis) as a Tier I at-risk species. Provided are some general management recommendations regarding the fringed myotis. 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 fringed myotis that will aid in the decision-making …


Local Attitudes Towards Bear Management After Illegal Feeding And Problem Bear Activity, Sara Dubois, David Fraser Sep 2013

Local Attitudes Towards Bear Management After Illegal Feeding And Problem Bear Activity, Sara Dubois, David Fraser

Wildlife Population Management Collection

The “pot bears” received international media attention in 2010 after police discovered the intentional feeding of over 20 black bears during the investigation of an alleged marijuana-growing operation in Christina Lake, British Columbia, Canada. A two-phase random digit dialing survey of the community was conducted in 2011 to understand local perspectives on bear policy and management, before and after a summer of problem bear activity and government interventions. Of the 159 households surveyed in February 2011, most had neutral or positive attitudes towards bears in general, and supported the initial decision to feed the food-conditioned bears until the autumn hibernation. …


Analysis Of Uniparental Lineages In Two Villages Of Santiago Del Estero, Argentina, Seat Of “Pueblos De Indios” In Colonial Times, Maia Pauro, Angelina García, Rodrigo Nores, Darío A. Demarchi Sep 2013

Analysis Of Uniparental Lineages In Two Villages Of Santiago Del Estero, Argentina, Seat Of “Pueblos De Indios” In Colonial Times, Maia Pauro, Angelina García, Rodrigo Nores, Darío A. Demarchi

Human Biology Open Access Pre-Prints

Based on the analysis of the mitochondrial control region and seven biallelic markers of the Y Chromosome, we investigated the genetic composition of two rural populations of southern Santiago del Estero, Argentina, that were seats in colonial times of “pueblos de indios”, a colonial practice that consisted of concentrating the indigenous populations in organized and accessible settlements, to facilitate Christianizing and policing. We found the Native American Y chromosome haplogroup Q1a3a in only 11% (3/27) of the males. Haplogroup R, common in European populations, is the most frequent haplogroup in Santiago del Estero (55%). In contrast, the persistence of Native …


Exploring The Relative Importance Of Spatial And Environmental Variation On The Craniometrics Of The Modern Portuguese, Katherine E. Weisensee Sep 2013

Exploring The Relative Importance Of Spatial And Environmental Variation On The Craniometrics Of The Modern Portuguese, Katherine E. Weisensee

Human Biology Open Access Pre-Prints

Previous research on the causes of craniometric variation within and among human populations has invoked both genetic and environmental explanations. Recent studies of modern populations in the United States and Portugal, among other populations, suggest that changes in environmental conditions have resulted in significant changes in cranial morphology. While similar changes in cranial morphology have been observed in genetically diverse populations, these populations do not appear to be converging on a common form. This study seeks to understand the role that population history and environmental variation play in explaining craniometric variation in the modern Portuguese. Using three-­‐dimensional craniometric data collected …


Feeling The Heat? Substantial Variation In Temperatures Does Not Affect The Proportion Of Males Born In Australia, Barnaby J. Dixson, John Haywood, Philip J. Lester, Diane K. Ormsby Sep 2013

Feeling The Heat? Substantial Variation In Temperatures Does Not Affect The Proportion Of Males Born In Australia, Barnaby J. Dixson, John Haywood, Philip J. Lester, Diane K. Ormsby

Human Biology Open Access Pre-Prints

The global proportion of male births has been shown to vary with climate, with a higher proportion of male births documented in colder climates. Here we examined the hypothesis that ambient temperature predicts fluctuations in the proportion of male births in Australia and within seven Australian states using historical annual data spanning 1910-2009. We predicted that within states with tropical ambient temperatures the proportion of male births would decrease when ambient temperatures are higher. Considering the national composite births for the whole of Australia first, the proportion of males born ranged only from 0.510 to 0.517. We observed no relationship …


Genetic Variation Of X-Strs In The Wichí Population From Chaco Province, Argentina, Laura Angela Glesmann, Pablo Francisco Martina, Cecilia Inés Catanesi Sep 2013

Genetic Variation Of X-Strs In The Wichí Population From Chaco Province, Argentina, Laura Angela Glesmann, Pablo Francisco Martina, Cecilia Inés Catanesi

Human Biology Open Access Pre-Prints

The Wichí people from Chaco province inhabit the region called Impenetrable Chaqueño, where the climatic conditions are extreme. Besides the scarce communication with the main urban centers, the cultural patterns of the Wichí cause these communities to live in certain degree of isolation. The effect of this situation is an increased genetic differentiation from other populations, as it was observed through autosomal and Y chromosome markers. However, the genetic variation of X chromosome has not been fully analyzed yet. The patterns of allele distribution of different markers of X chromosome can be highly informative in comparative studies, because its special …


The Genus Odontophrynus (Anura: Odontophrynidae): A Larval Perspective, Filipe Augusto C. Do Nascimento, Tamí Mott, José A. Langone, Christine A. Davis, Rafael O. De Sá Aug 2013

The Genus Odontophrynus (Anura: Odontophrynidae): A Larval Perspective, Filipe Augusto C. Do Nascimento, Tamí Mott, José A. Langone, Christine A. Davis, Rafael O. De Sá

Biology Faculty Publications

The genus Odontophrynus consists of 11 species of medium-sized frogs distributed across south and east South America. This study examines and describes the chondrocrania and oral cavities of 0. americanus, 0. maisuma, 0. carvalhoi, and 0. cu/tripes, and reviews current knowledge about the larval external morphology of the genus. Twenty-one tadpoles were cleared and double-stained for chondrocranium description and five tadpoles were dissected for analysis in a scanning electron microscope. The presence of a tectum parientale may be considered here as a putative synapomorphy of the genus. The 0. americanus and 0. cu/tripes species groups were partially differentiated by the …


Big Babies, Big Mammas?: Relationship Of Leatherback Hatchling Size And Mother Size, Shane Morales, Violet Campbell, Kelly Stewart Aug 2013

Big Babies, Big Mammas?: Relationship Of Leatherback Hatchling Size And Mother Size, Shane Morales, Violet Campbell, Kelly Stewart

STAR Program Research Presentations

Individual leatherback hatchlings vary in size when compared to individuals from other nests, as well as individuals from the same nest. It is thought that many factors affect hatchling size but that one of the most influential factors is maternal size. Of all the aspects of a mother which could affect hatchling size, evidence for question concerning influence of mother size is determinable within the field using minimal tools and basic statistical analysis. If a direct correlation exists between mother size and hatchling size then the claim can be made that larger mothers produce larger offspring while smaller mothers produce …


Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer Aug 2013

Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer

STAR Program Research Presentations

As potential predators and competitors of plankton-eating fish, jellyfish have the potential to negatively impact fish populations. Jellyfish were collected weekly with plankton tows from the RombergTiburonCenterpier in Tiburon, CA. Since some jellyfish were too small to identify, one tow was collected and preserved to record abundances, and a second tow was collected to rear jellyfish until distinguishing characteristics were visible enough for identification. Jellyfish in the preserved tows were then identified, measured, and counted, and their abundance (number m-3) was calculated. Jellyfish from the second tows were reared in plastic buckets that were lightly bubbled using aquarium …


Greater Prairie-Chicken Nest Success And Habitat Selection In Southeastern Nebraska, Ty W. Matthews, Andrew J. Tyre, J. Scott Taylor, Jeffrey J. Lusk, Larkin A. Powell Aug 2013

Greater Prairie-Chicken Nest Success And Habitat Selection In Southeastern Nebraska, Ty W. Matthews, Andrew J. Tyre, J. Scott Taylor, Jeffrey J. Lusk, Larkin A. Powell

School of Natural Resources: Faculty Publications

Greater prairie-chickens (Tympanuchus cupido pinnatus) are reported to benefit from grasslands created through the Conservation Reserve Program (CRP). Prairie-chicken population size increased noticeably in southeastern Nebraska after >15% of county-level landscapes were converted to CRP grasslands. But, the mechanisms behind the increase in population size are not well understood, and managers and policy makers could benefit from evidence of CRP’s relative contribution to populations of prairie-chickens. Therefore, our objectives were to characterize the relations of vegetation structure and composition with prairie-chicken nest-site selection and nest survival rates at both the macrohabitat (within landscape of study site) and microhabitat …


Cause And Impacts Of The Early Season Collapse Of Lilium Grayi (Gray’S Lily), On Roan Mountain, Tn/Nc, Russell J. Ingram Aug 2013

Cause And Impacts Of The Early Season Collapse Of Lilium Grayi (Gray’S Lily), On Roan Mountain, Tn/Nc, Russell J. Ingram

Electronic Theses and Dissertations

A population of the rare Southern Appalachian endemic species Lilium grayi, (Gray’s lily) Roan Mountain, TN/NC was monitored for 2 years to determine the cause and impact of an early season collapse. High concentrations of the Lilium spp. host-specific fungal phytopathogen, Pseudocercosporella inconspicua (G. Winter) U. Braun were associated with 19/20 symptomatic and 0/30 asymptomatic plants. Strength of the association between pathogen and disease and the replication of disease symptoms in 4/4 healthy hosts showed that P. inconspicua was the causal agent of the disease referred to as lily leaf spot. Disease had a severe impact on the population …


Reproductive Isolation And Cryptic Introgression In A Sky Island Enclave Of Appalachian Birds, Gene D. Sattler, Michael J. Braun Aug 2013

Reproductive Isolation And Cryptic Introgression In A Sky Island Enclave Of Appalachian Birds, Gene D. Sattler, Michael J. Braun

Faculty Publications and Presentations

Reproductive isolation is central to the speciation process, and cases where the strength of reproductive isolation varies geographically can inform our understanding of speciation mechanisms. Although generally treated as separate species, Black-capped chickadees (Poecile atricapillus) and Carolina chickadees (P. carolinensis) hybridize and undergo genetic introgression in many areas where they come into contact across the eastern United States and in the northern Appalachian Mountains. The Great Smoky Mountains harbor the last large breeding population of atricapillus in the southern Appalachians, isolated from the species’ main range by nearly 200 km. This population is believed to be reproductively isolated from local …


Genetic And Morphological Variation In Taeniatherum Caput-Medusae (Medusahead): Taxomonic Diversity, Geographic Origins, Multiple Introductions And Founder Effects, Morgan Lindsey Peters Aug 2013

Genetic And Morphological Variation In Taeniatherum Caput-Medusae (Medusahead): Taxomonic Diversity, Geographic Origins, Multiple Introductions And Founder Effects, Morgan Lindsey Peters

Boise State University Theses and Dissertations

Invasive species are novel to a region, thus their timely and accurate identification is a critical first step in recognizing and managing the threats that they may present in their new habitats. Accurate identification of an introduced species in its new range can prove difficult however for a species that displays taxonomic complexity in its native range, i.e. consists of multiple, morphologically similar subspecies.

Across its native range, Taeniatherum caput-medusae (medusahead) exhibits taxonomic complexity. Three subspecies have been recognized: T. caput-medusae ssp. caput-medusae, T. caput-medusae ssp.asperum, and T. caput-medusae ssp. crinitum. While subspecies …


Ecology And Structure Of Black Bear (Ursus Americanus) Populations In The Interior Highlands Of Arkansas, Thea Vandervelde Kristensen Aug 2013

Ecology And Structure Of Black Bear (Ursus Americanus) Populations In The Interior Highlands Of Arkansas, Thea Vandervelde Kristensen

Graduate Theses and Dissertations

In the Interior Highlands of Arkansas, Missouri, and Oklahoma, over-harvest, extensive logging, and reductions of habitat availability by other means contributed to the decline of black bears (Ursus americanus). Bears were extirpated from the majority of the region by the 1940's Oklahoma by 1915 and from Missouri by 1931. From 1958-1968, the Arkansas Game and Fish Commission undertook a reintroduction to the Ouachita and the Ozark National Forests in Arkansas. The successful growth and expansion of the released population caused these efforts to be considered one of the most successful reintroductions of carnivores. In this dissertation, I sought to examine …


The Interactive Effects Of Multiple Stressors On Lithobates Catesbeianus And Anaxyrus Americanus, Matthew Kyle Holden Aug 2013

The Interactive Effects Of Multiple Stressors On Lithobates Catesbeianus And Anaxyrus Americanus, Matthew Kyle Holden

Graduate Theses and Dissertations

Amphibian populations worldwide have experienced dramatic declines, and many species have already become locally, regionally, or globally extirpated with thousands more being threatened with extinction. These declines have occurred more rapidly in amphibians than any other group of vertebrates, which is especially concerning to scientists because amphibians serve as indicator species of overall environmental health. Major causes for amphibian declines are discussed in Chapter 1 and include: habitat modification and destruction, commercial over-exploitation, introduced species, environmental contaminants, global climate change, and infectious diseases.

Chapter 2 discusses the major research aspects of the thesis by examining the interactive effects of multiple …


Exploitation Of Channel Catfish In Nebraska Flood-Control Reservoirs, Christopher Lee Wiley Jul 2013

Exploitation Of Channel Catfish In Nebraska Flood-Control Reservoirs, Christopher Lee Wiley

School of Natural Resources: Dissertations, Theses, and Student Research

Channel catfish Ictalurus punctatus, is a popular sportfish in North America, and is the third most-sought fish species in Nebraska. Exploitation rates of channel catfish populations have been estimated to be substantial in states neighboring Nebraska. Despite the popularity of channel catfish, little is known about the exploitation of channel catfish populations in Nebraska. The objectives of this study were to estimate the exploitation rates of channel catfish populations, identify the length bias of angling for channel catfish, and identify the self-imposed length limits for channel catfish at flood-control reservoirs of Nebraska. The software package Program Mark was used to …


The Birds Of Nebraska, Revised Edition 2013, Paul A. Johnsgard Jul 2013

The Birds Of Nebraska, Revised Edition 2013, Paul A. Johnsgard

Zea E-Books Collection

This summary of the birds of Nebraska has been restricted to those species that have been convincingly reported at least once in Nebraska from historic time to the present. It has also been modified in its current revision to conform very closely in that regard to the most recent Nebraska Ornithologists’ Union’s “Official List of the Birds of Nebraska” (Brogie, 2010; NOU Records Committee, 2011 and annual updates). The N.O.U.’s official state list of birds (455 species as of 2013, including 329 “regular” species, 42 of “casual” occurrence, 68 accidentals, and six extinct or extirpated species) is based on actual …