Physical Sciences and Mathematics Commons^™

Assessment Of Smallmouth Bass Growth And Mortality In Nebraska Waters, Benjamin J. Schall, Keith D. Koupal, Casey W. Schoenebeck, Keith L. Hurley

The Prairie Naturalist

Smallmouth bass (Micropterus dolomieu) have been introduced across Nebraska into a variety of waterbodies. However, an estimate of smallmouth bass growth and mortality in Nebraska waters has not been produced. The objectives of this study were to use historic sampling data to describe the growth of smallmouth bass in Nebraska lakes in relation to other regional models, growth among waterbody types (reservoirs, Interstate 80 [I-80] lakes, and rivers), estimates of age at quality, preferred, and memorable lengths, and mortality for Nebraska smallmouth bass populations. Mean length ± SE of Nebraska smallmouth bass at age 7 was 383 ± …

River Otter (Lontra Canadensis) Distribution And Habitat Suitability In Nebraska, Nathan R. Bieber

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

River otters (Lontra Canadensis) were extirpated in Nebraska by the early 1900’s, but in 1986, the Nebraska Game and Parks Commission (NGPC) began reintroduction efforts. Following reintroductions, the otter was listed as a tier-1 at-risk species in Nebraska. With increasing otter populations, NGPC is evaluating a de-listing plan. In order to inform de-listing efforts, I surveyed Nebraska’s rivers documenting otter sign and used modeling techniques to estimate otter distribution and habitat suitability.

Otter sign surveys were conducted on the navigable rivers of Nebraska. Occupancy modeling techniques were used to examine patterns in otter detections. The best model incorporated distance …

Fidelity And Survival Of Breeding Mallards In The Nebraska Sandhills, Zachary J. Cunningham, Larkin Powell, Mark P. Vrtiska

The Prairie Naturalist

Assessment of demographic parameters of a population allows managers to better understand factors affecting populations and increase efficiency of conservation efforts. Few data on demographics exist for mallards (Anas platyrhynchos) breeding in the Nebraska Sandhills. Thus, we used banding data to estimate probabilities of fidelity, survival, band recovery, and recapture of mallards banded in the eastern Sandhills, 2005–2008. Our recapture probability estimate for mallards was 0.074 (95% CI: 0.033–0.158), and the recovery probability estimate was 0.300 (95% CI: 0.156–0.497). Mallard annual survival was 0.795 (95% CI: 0.609–0.906) with a fidelity probability of 0.618 (95% CI: 0.283–0.868). High annual …

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …