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Full-Text Articles in Animal Sciences
Population Characteristics, Development Of A Predictive Population Viability Model, And Catch Dynamics For Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen
Population Characteristics, Development Of A Predictive Population Viability Model, And Catch Dynamics For Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen
School of Natural Resources: Dissertations, Theses, and Student Research
Population characteristics and long-term population trends of pallid sturgeon Scaphirhynchus albus in the lower Missouri River are relatively unknown. As recovery efforts continue, understanding and quantifying these characteristics and trends are critical for species recovery and future management decisions. Therefore, the objectives of this study were to determine the pallid sturgeon population characteristics, predict changes to the pallid sturgeon population based on different management and life history scenarios, and examine trot line catch dynamics in the lower Missouri River. Catch rates for pallid sturgeon collected with gill nets did not significantly change while catch rates using trot lines significantly declined …
Winter Ecology Of Sandhill Cranes (Grus Canandensis) In Northern Mexico, Ingrid Barcelo
Winter Ecology Of Sandhill Cranes (Grus Canandensis) In Northern Mexico, Ingrid Barcelo
School of Natural Resources: Dissertations, Theses, and Student Research
Sandhill Cranes (Grus canadensis) are a widespread species in North America and one of the most studied cranes in the world. However, most of the research has focused on the breeding grounds of Canada and Alaska and the staging grounds of Nebraska. Although an important proportion of the Mid-continent Population of Sandhill Cranes winters in northern Mexico, little information exists on distribution, status, and ecology of the species in Mexico. The goal of this dissertation was to provide new information on Sandhill Crane winter ecology from a regional perspective to better understand population trends. I examined the physiological …
Effects Of Length Limits On Sexually Size Dimorphic Fishes, Peter J. Spirk
Effects Of Length Limits On Sexually Size Dimorphic Fishes, Peter J. Spirk
School of Natural Resources: Dissertations, Theses, and Student Research
Length limits are used by fishery managers as a method to alter size structure of fish populations. Unfortunately, biological differences between fish sexes (i.e., sexual-size dimorphism) may lead to sex-specific rates of recruitment, growth, and mortality. The addition of angler harvest to most aquatic systems likely accentuates differences in sex-specific rates by selectively harvesting the fastest-growing and largest fish from a population. The first objective of this study was to document the extent of sexual-size dimorphism for white bass and walleye at a Nebraska reservoir. Growth rates were similar between male and female white bass although male white bass were …
Stopover Decisions Of Migratory Shorebirds: An Assessment Of Habitat Use, Food Availability, Behavior And Phenology, Ryan Stutzman
Stopover Decisions Of Migratory Shorebirds: An Assessment Of Habitat Use, Food Availability, Behavior And Phenology, Ryan Stutzman
School of Natural Resources: Dissertations, Theses, and Student Research
Habitat loss and alteration from land use change, species invasion, and more recently, climate change has reduced biodiversity and ecosystem function worldwide. Habitat decisions have important implications to individual fitness as well as population dynamics and community structure. Resource limitation, predation, competition, and unfavorable abiotic conditions all have the potential to influence survival and future reproductive potential. Understanding how changes to ecosystem structure and function impact species and populations of conservation concern is essential for conservation delivery to be effective. Similar to many migratory species, shorebird populations are declining worldwide and declines may be related to the loss of important …