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Full-Text Articles in Life Sciences

Habitat Selection By Desert Carnivores: How Water, Intraguild Predation, And Prey Impact Animal Space Use, Nadine A. Pershyn May 2023

Habitat Selection By Desert Carnivores: How Water, Intraguild Predation, And Prey Impact Animal Space Use, Nadine A. Pershyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Across North America large carnivores have lost nearly half of their historic range, creating openings for smaller (< 15 kg) carnivores to take over their ecological roles. Coyotes (Canis latrans) have seen a significant range expansion, including into arid deserts. It was believed that the addition of artificial water sources by humans allowed coyotes to expand into desert ecosystems where they were previously unable to survive. The kit fox (Vulpes macrotis) is a small, desert-adapted carnivore with declining populations that faces threats from coyotes of intraguild predation. This is when carnivores compete over the same prey, and the larger carnivore (intraguild predator) kills the smaller carnivore (intraguild …


Intraspecific Variation In Prey Susceptibility Mediates The Consumptive Effect Of Predation: A Case Study Of Yellowstone Elk And Wolves, Lacy M. Smith Dec 2021

Intraspecific Variation In Prey Susceptibility Mediates The Consumptive Effect Of Predation: A Case Study Of Yellowstone Elk And Wolves, Lacy M. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The reintroduction of wolves (Canis lupus) to Yellowstone National Park starting in 1995 is an important case study for understanding the consequences of predation on a prey population. Simulation studies conducted prior to and shortly after wolf reintroduction predicted that wolf predation of elk (Cervus canadensis) would have a modest influence on elk abundance. Predation of elk by wolves has been well documented and elk have remained the primary prey for wolves despite a decline in elk abundance. I used two quantitative approaches to estimate the influence of wolf predation on adult female elk survival and …


Thinking Like A Raven: Restoring Integrity, Stability, And Beauty To Western Ecosystems, John M. Marzluff, Matthias-Claudio Loretto, Cameron K. Ho, Georgia W. Coleman, Marco Restani Jan 2021

Thinking Like A Raven: Restoring Integrity, Stability, And Beauty To Western Ecosystems, John M. Marzluff, Matthias-Claudio Loretto, Cameron K. Ho, Georgia W. Coleman, Marco Restani

Human–Wildlife Interactions

Common ravens (Corvus corax; ravens) are generalist predators that pose a threat to several rare wildlife species in the western United States. Recent increases in raven populations, which are fueled by increased human subsidies—notably food, water, and nest sites—are concerning to those seeking to conserve rare species. Due to the challenges and inefficiencies of reducing or eliminating subsidies, managers increasingly rely on lethal removal of ravens. Over 125,000 ravens were killed by the U.S. Government from 1996 to 2019, and annual removals have increased 4-fold from the 1990s to mid-2010s. We contend that lethal removal of ravens, while capable …


Common Ravens Disrupt Greater Sage-Grouse Lekking Behavior In The Great Basin, Usa, Joseph L. Atkinson, Peter S. Coates, Brianne E. Brussee, Ian A. Dwight, Mark A. Ricca, Pat J. Jackson Jan 2021

Common Ravens Disrupt Greater Sage-Grouse Lekking Behavior In The Great Basin, Usa, Joseph L. Atkinson, Peter S. Coates, Brianne E. Brussee, Ian A. Dwight, Mark A. Ricca, Pat J. Jackson

Human–Wildlife Interactions

Expansion of human enterprise has contributed to increased abundance and distribution of common ravens (Corvus corax; ravens) across sagebrush (Artemisia spp.) ecosystems within western North America. Ravens are highly effective nest predators of greater sage-grouse (Centrocercus urophasianus; sage-grouse), a species of high conservation concern. Sage-grouse population trends are estimated using count survey data of males attending traditional breeding grounds, known as leks. We sought to investigate associations of ravens to sage-grouse lek sites and document interactions between the sage-grouse and ravens as well as those between sage-grouse and other animals observed around leks. First, we …


Anthropogenic Disturbance And Population Viability Of Woodland Caribou In Ontario, John M. Fryxell, Tal Avgar, Boyan Liu, James A. Baker, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, Douglas E. B. Reid, Andrew M. Kittle, Anna Mosser, Steven G. Newmaster, Tom D. Nudds, Garrett M. Street, Glen S. Brown, Brent Patterson Feb 2020

Anthropogenic Disturbance And Population Viability Of Woodland Caribou In Ontario, John M. Fryxell, Tal Avgar, Boyan Liu, James A. Baker, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, Douglas E. B. Reid, Andrew M. Kittle, Anna Mosser, Steven G. Newmaster, Tom D. Nudds, Garrett M. Street, Glen S. Brown, Brent Patterson

Wildland Resources Faculty Publications

One of the most challenging tasks in wildlife conservation and management is to clarify how spatial variation in land cover due to anthropogenic disturbance influences wildlife demography and long‐term viability. To evaluate this, we compared rates of survival and population growth by woodland caribou (Rangifer tarandus caribou) from 2 study sites in northern Ontario, Canada that differed in the degree of anthropogenic disturbance because of commercial logging and road development, resulting in differences in predation risk due to gray wolves (Canis lupus). We used an individual‐based model for population viability analysis (PVA) that incorporated adaptive patterns …


Humans As Prey: Coping With Large Carnivore Attacks Using A Predator-Prey Interaction Perspective, Vincenzo Penteriani, Giulia Bombieri, José María Fedriani, José Vicente López-Bao, Pedro José Garrote, Luca Francesco Russo, María Del Mar Delgado Sep 2017

Humans As Prey: Coping With Large Carnivore Attacks Using A Predator-Prey Interaction Perspective, Vincenzo Penteriani, Giulia Bombieri, José María Fedriani, José Vicente López-Bao, Pedro José Garrote, Luca Francesco Russo, María Del Mar Delgado

Human–Wildlife Interactions

The number of attacks on humans by large carnivores in North America is increasing. A better understanding the factors triggering such attacks is critical to mitigating the risk of future encounters in landscape where humans and large carnivore co-exist. Since 1955, of the 632 attacks on humans by large carnivores, 106 (17%) involved predation. We draw on concepts and empirical evidence from the Predator-Prey Interaction Theory to provide insights into how to reduce predatory attacks and, thus, improve human-large carnivore co-existence. Because large carnivore-caused mortality risks for humans are comparable to those shown by other mammal species in response to …


Use Of Predator Hair To Enhance Perceived Risk To White-Tailed Deer In A Foraging Context, Thomas W. Seamans, Bradley F. Blackwell, Kimberly E. Linnell Jan 2016

Use Of Predator Hair To Enhance Perceived Risk To White-Tailed Deer In A Foraging Context, Thomas W. Seamans, Bradley F. Blackwell, Kimberly E. Linnell

Human–Wildlife Interactions

Deer react to predator scent in varying degrees even when exposed to unknown predators. This response could be genetically based and maintained as long as the population is exposed to predation. We tested whether predator scent in the form of hair would enhance perceived risk and serve as a foraging repellent to free-ranging white-tailed deer (Odocoileus virginianus). During the winters of 2013 and 2014, we quantified alert behaviors and consumption of whole-kernel corn in response to current (coyote [Canis latrans]) and extirpated (bobcat [Lynx rufus]; black bear [Ursus americanus]) predator species alone …


Cougar Predation Behavior In North-Central Utah, Dustin L. Mitchell May 2013

Cougar Predation Behavior In North-Central Utah, Dustin L. Mitchell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Today’s ability to apply global positioning systems (GPS) collars to wild animals and track their movements, without inadvertently disrupting their daily routine, is a major benefit to wildlife research. Cougars are carnivorous predators that have been identified as being one of several possible causes for recent mule deer population declines throughout the Western United States. Past cougar predation studies have relied on snow tracking, radio-collar tracking, and modeling techniques to estimate cougar prey use and predation rates. These methods rely heavily on weather conditions, logistical availabilities, and broad assumptions, which have led to a wide range of predation rate estimates. …


Management Of Double-Crested Cormorants To Improve Sport Fisheries In Michigan: Three Case Studies, Brian S. Dorr, Shauna L. Hanisch, Peter H. Butchko, David G. Fielder Jan 2012

Management Of Double-Crested Cormorants To Improve Sport Fisheries In Michigan: Three Case Studies, Brian S. Dorr, Shauna L. Hanisch, Peter H. Butchko, David G. Fielder

Human–Wildlife Interactions

Impacts of double-crested cormorants (Phalacrocorax auritus) to fisheries have been documented, but evaluation of the process and outcomes of cormorant management to reduce impacts on fisheries is lacking. We provide a synthesis of adaptive management of double-crested cormorants in the Les Cheneaux Islands (LCI), Brevoort Lake, and Drummond Island, Michigan from 2004 to 2007. The LCI management focused on reducing numbers of nesting cormorants in the region as a means of improving the yellow perch (Perca flavescens) population and fishery. At Brevoort Lake and Drummond Island, management focused on lethal and nonlethal harassment of spring migrating …


Mixed-Breed Guarding Dogs Reduce Conflict Between Goat Herders And Native Carnivores In Patagonia, Alejandro González, Andrés Novaro, Martín Funes, Oscar Pailacura, María Jose Bolgeri, Susan Walker Jan 2012

Mixed-Breed Guarding Dogs Reduce Conflict Between Goat Herders And Native Carnivores In Patagonia, Alejandro González, Andrés Novaro, Martín Funes, Oscar Pailacura, María Jose Bolgeri, Susan Walker

Human–Wildlife Interactions

Goat husbandry is the main rural livelihood in the northern Patagonian steppe of Argentina, and herders kill any carnivore that they believe threatens their herds, including the endangered Andean cat (Leopardus jacobita). We evaluated the use of local, mediumsized, mixed-breed guarding dogs to reduce predation and retaliatory killing of carnivores. We interviewed 64 herders, and delivered 37 puppies to 25 herders. Most economic loss was attributed to cougars (Puma concolor) and culpeos (Lycalopex culpaeus). All herders with dogs that reached the working stage reported reduced rates of predation, and 88% reported that they no …


Habitat Correlates Of Jaguar Kill-Sites Of Cattle In Northeastern Sonora, Mexico, Octavio C. Rosas-Rosas, Louis C. Bender, Raul Valdez Jan 2010

Habitat Correlates Of Jaguar Kill-Sites Of Cattle In Northeastern Sonora, Mexico, Octavio C. Rosas-Rosas, Louis C. Bender, Raul Valdez

Human–Wildlife Interactions

Predation on cattle by the endangered jaguar (Panthera onca) can be a serious ecological and economic conflict. We investigated habitat characteristics of kill sites of cattle in Sonora, Mexico, from 1999 to 2004 to see whether habitat management or cattle distribution could be used as effective nonlethal methods to limit predation. Kill-sites were positively associated with oak, semitropical thornscrub, and xeric thornscrub vegetation types, whereas they were negatively associated with upland mesquite. Sites of cattle kills were also positively associated with proximity to permanent water sources and roads. A model including these relationships fi t kill locations well …


Absence Of Predation Eliminates Coexistence: Experience From The Fish-Zooplankton Interface, Z. M. Gilwicz, Wayne A. Wurtsbaugh, E. Szymansk Jan 2010

Absence Of Predation Eliminates Coexistence: Experience From The Fish-Zooplankton Interface, Z. M. Gilwicz, Wayne A. Wurtsbaugh, E. Szymansk

Watershed Sciences Faculty Publications

Examples from fishless aquatic habitats show that competition among zooplankton for resources instigates rapid exclusion of competitively inferior species in the absence of fish predation, and leads to resource monopolization by the superior competitor. This may be a single species or a few clones with large body size: a cladoceran such as Daphnia pulicaria, or a branchiopod such as Artemia franciscana, each building its population to a density far higher than those found in habitats with fish. The example of zooplankton from two different fish-free habitats demonstrates the overpowering force of fish predation by highlighting the consequences of its absence. …


Using Predator Exclosures To Protect Ground Nests From Red Fox, Ben C. West, Terry A. Messmer, Dominic C. Bachman Jan 2007

Using Predator Exclosures To Protect Ground Nests From Red Fox, Ben C. West, Terry A. Messmer, Dominic C. Bachman

Human–Wildlife Interactions

Nest predation often is cited as a primary cause for low recruitment and subsequent population decline of many ground-nesting bird species. In response, managers and researchers have developed a myriad of techniques to reduce rates of predation on ground nests. Fences to exclude predators from nesting areas have reportedly been a successful, albeit expensive, strategy to reduce predation rates. Although many studies have evaluated the use of exclusionary fences as a management tool, nearly all of these studies have evaluated the impact of fences in terms of nest success rather than by actual fence penetration by predators. Many authors, for …


Nest Success Of Dabbling Ducks In A Human-Modified Prairie: Effects Of Predation And Habitat Variables At Different Spatial Scales, Jaime E. Jimenez May 1999

Nest Success Of Dabbling Ducks In A Human-Modified Prairie: Effects Of Predation And Habitat Variables At Different Spatial Scales, Jaime E. Jimenez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nest success of dabbling ducks in the Prairie Pothole region of North America has been declining for the past 40 years in parallel with declines in duck populations. Low nest success seems to result from the combination of an extremely fragmented breeding ground in a human-dominated landscape with an abundant and expanding community of generalist nest predators. Studies that examined variables associated with nest vulnerability to predation have produced contradictory results, likely because of simplistic approaches, lack of spatio-temporal replication, use of artificial nests, and the effect of confounding variables. I attempted to clarify the equivocal findings of previous studies …


The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems: Field Observations And An Experimental Study On Predation, Roger Allen Tabor May 1990

The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems: Field Observations And An Experimental Study On Predation, Roger Allen Tabor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Juvenile rainbow trout Oncorhynchus mykiss stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by (1) direct observations (snorkel transects) of habitat selection in two reservoirs and (2) measurements of survival and growth rates in a pond experiment where adult brown trout Salmo trutta were predators. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day, juvenile trout were abundant in complex inshore habitats and avoided simple habitats such as sand and gravel. Measurements …


Importance Of Predation By Adult Trout On Mortality Rates Of Fingerling Rainbow Trout Stocked In East Canyon Reservoir, Utah, Wayne A. Wurtsbaugh Jan 1987

Importance Of Predation By Adult Trout On Mortality Rates Of Fingerling Rainbow Trout Stocked In East Canyon Reservoir, Utah, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Personnel from Utah State University, working in cooperation with the Utah Division of Wildlife Resources and the Utah Cooperative Fish and Wildlife Research Unit, are attempting to determine various sources of mortality of fingerling rainbow trout (Salmo gairdneri) stocked into mid-elevation reservoirs in the State. Returns of planted fish are often much below desired levels. Angler surveys indicate that in East Canyon Reservoir, fishermen harvest only about 30% of the fingerling trout stocked, and this is a much higher return than in many other waters.