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Full-Text Articles in Life Sciences

Primnoa Pacifica Reproduction In Shallow Versus Deep Habitats Of Glacier Bay National Park And Preserve, Alaska, Ciara N. Larence Dec 2021

Primnoa Pacifica Reproduction In Shallow Versus Deep Habitats Of Glacier Bay National Park And Preserve, Alaska, Ciara N. Larence

Honors College

Primnoa pacifica is a species of deep-sea cold-water coral that can be found in Glacier Bay National Park and Preserve in Alaska. These colonies are important to their ecosystem as they provide habitat for other species living in this area. One thing that makes P. pacifica important to study is that the species displays deep-water emergence. This is a phenomenon where species normally found in deep waters can exist in shallower waters, allowing easier access for research. The purpose of this thesis was to determine if depth effects the reproduction of male P. pacifica colonies. Two colonies from deep depths …


Effects Of Glacial Stressors On Sperm Maturation In Colonies Of The Red Tree Coral, Primnoa Pacifica, Joshua Lynn Dec 2021

Effects Of Glacial Stressors On Sperm Maturation In Colonies Of The Red Tree Coral, Primnoa Pacifica, Joshua Lynn

Honors College

The red tree coral, Primnoa pacifica, is a large, colony forming species of cold- water coral which is often an important habitat for many commercially important species of fish and crab. This keystone species is long lived and found at much shallower depths in the fjords of Glacier Bay National Park (GBNP) than elsewhere in the northern Pacific Ocean because of the phenomenon known as deep-water emergence. Due to their proximity to tidewater glaciers in GBNP, corals likely have to endure glacial stressors such as freshwater runoff and sedimentation that is not typical of populations in deeper water, which …


Observations On The Distribution And Status Of Selected Nebraska Mammals, Zachary P. Roehrs, Russell A. Benedict, Thomas E. Labedz, Hugh H. Genoways Feb 2021

Observations On The Distribution And Status Of Selected Nebraska Mammals, Zachary P. Roehrs, Russell A. Benedict, Thomas E. Labedz, Hugh H. Genoways

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Information on the distribution and current status of 25 species or subspecies of mammals occurring in Nebraska are presented. The species covered include one shrew, an armadillo, eight bats, 10 rodents (including two subspecies of one species), three carnivores, and one artiodactyl. Distributional information reported includes the first state record for one species (Sorex nanus) and new county records for 18 species. In Nebraska, we know that mammals are shifting their geographic ranges with some extending populations into the state, whereas others are expanding their geographic ranges within the state. The current status of six additional mammalian taxa …


Kelp-Associated Microbes Facilitate Spatial Subsidy In A Detrital-Based Food Web In A Shoreline Ecosystem, Charu Lata Singh, Megan J. Huggett, Paul S. Lavery, Christin Säwström, Glenn A. Hyndes Jan 2021

Kelp-Associated Microbes Facilitate Spatial Subsidy In A Detrital-Based Food Web In A Shoreline Ecosystem, Charu Lata Singh, Megan J. Huggett, Paul S. Lavery, Christin Säwström, Glenn A. Hyndes

Research outputs 2014 to 2021

Microbes are ubiquitous but our knowledge of their effects on consumers is limited in benthic marine systems. Shorelines often form hotspots of microbial and detritivore activity due to the large amounts of detrital macrophytes that are exported from other coastal ecosystems, such as kelp forests, and accumulate in these systems. Shoreline ecosystems therefore provide a useful model system to examine microbial-detritivore interactions. We experimentally test whether bacteria in the biofilm of kelp provide a bottom-up influence on growth and reproductive output of detritivores in shorelines where detrital kelp accumulates, by manipulating the bacterial abundances on kelp (Ecklonia radiata). The growth …


Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French Jan 2021

Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French

United States Department of Agriculture Wildlife Services: Staff Publications

Polar bears (Ursus maritimus) use sea ice to access marine mammal prey. In Alaska’s Southern Beaufort Sea, the declining availability of sea ice habitat in summer and fall has reduced opportunities for polar bears to routinely hunt on the ice for seals, their primary prey. This reduced access to prey may result in physiological stress with subsequent potential consequences to reproductive function (physiological changes that accompany reproduction), which can be measured via reproductive hormones. Hormone concentrations in hair can be used as a minimally invasive alternative to serum concentrations, which must come from animal captures. Hair samples also …


Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young Jan 2021

Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) involved in depredation of livestock, an act frequently resulting in human-wildlife conflict, often do so out of necessity for provisioning pups. Surgical sterilization methods such as vasectomy that preserve gonadal hormones have been successful in reducing depredation by free-ranging coyotes while allowing individuals to maintain territoriality and mate fidelity. However, use of these methods remain costly and ineffective for wide-scale use. Given the alternative proposal of using chemical sterilization techniques, we investigated whether the use of hormone-altering sterilization methods impacted behavior of captive coyote pairs (i.e., male-female pair bonds). Our objective was to evaluate behavior …


Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry Jan 2021

Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry

United States Department of Agriculture Wildlife Services: Staff Publications

Life history theory predicts that there should be an inverse relationship between offspring size and number, because individuals cannot simultaneously maximize both when resources are limited. Although extensively studied in avian species, the occurrence and determinants of reproductive tradeoffs in oviparous reptiles are far less understood, particularly in parthenogenetic species. We studied this trade-off in the Colorado Checkered Whiptail, Aspidoscelis neotesselatus, a female-only parthenogenetic lizard. Using data previously collected in 2018 and 2019, we tested for clutch and egg size trade-offs and determined whether this relationship could be influenced by female size and aspects of physiological condition. Physiological condition …