Terrestrial and Aquatic Ecology Commons^™

Limitations Of Invasive Snake Control Tools In The Context Of A New Invasion On An Island With Abundant Prey, Shane R. Siers, Melia G. Nafus, Jereid E. Calaor, Rachel M. Volsteadt, Matthew S. Grassi, Megan Volsteadt, Aaron F. Collins, Patrick D. Barnhart, Logan T. Huse, Amy A. Yackel Adams, Diane L. Vice

United States Department of Agriculture Wildlife Services: Staff Publications

In October 2020, a new population of invasive brown treesnakes (Boiga irregularis) was discovered on the 33-ha Cocos Island, 2.5 km off the south coast of Guam, United States. Cocos Island is a unique conservation resource, providing refuge for many lizards and birds, including endangered species, which were extirpated from mainland Guam by invasive predators including brown treesnakes. We sought to evaluate the usefulness of toxic baiting with acetaminophen-treated carrion baits and cage trapping, common tools for the control of brown treesnakes on mainland Guam, as potential eradication tools on Cocos Island. We evaluated multiple bait types and …

Site-Specific Space Use And Resource Selection By Black Vultures (Coragyps Atratus) In The Southeastern Usa, Betsy Evans, John S. Humphrey, Eric A. Tillman, Michael L. Avery, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

North American populations of Black Vultures Coragyps atratus have increased and expanded their distribution in the southern and eastern USA. In conjunction with these patterns has been a rise in human–vulture conflicts. To improve our understanding of space use patterns and better inform management, we evaluated the movements of Black Vultures (n = 23) in the southeastern USA using a long-term GPS tracking database. Our specific objectives were to: (1) quantify home-range sizes in relation to season and geographical study location and (2) examine within-home-range resource selection to identify landscape and anthropogenic factors influencing roost and diurnal space use. …

Antipredator Blood-Squirting Defense In Horned Lizards (Phrynosoma): Chemical Isolation Of Plasma Component(S), Pogonomyrmex Ant Dietary Origin, And Evolution, Wade C. Sherbrooke, Bruce A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

North American horned lizards of the genus Phrynosoma are largely myrmecophagous and squirt systemic blood from circumocular sinuses during encounters with certain mammalian predators. The predators react with distinct revulsion. Using bioassay-guided fractionation of blood plasma, we endeavored to identify the source and characteristics of the active chemical compound(s) responsible for this negative oral response. Our results of coyote bioassays and a series of novel mouse bioassay experiments were largely concordant. The active compound(s) was likely plasma-borne with a molecular weight (mw) of between 800 and 1,600. To identify the source of the active compound(s), we noted bioassay responses …

Eradication Of Feral Swine From A Barrier Island In Florida, Usa: An Examination Of Effort And Multi-Method, Multi-Species Population Indexing, Richard M. Engeman, Eric A. Tillman, Betsy A. Evans, John C. Griffin, Garrison Grobaski, Bradley S. Smith, John Stark, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine (Sus scrofa) were targeted for and successfully eradicated from Saint Vincent Island (SVI), a National Wildlife Refuge (NWR) along the coast of Florida’s panhandle to protect its habitats and uncharacteristically high diversity of wildlife species for barrier islands in the region, including federal and state-listed threatened and endangered species. The eradication effort was initiated in early 2015 and concluded in 2019. A total of 438 feral swine were removed from the Island, 417 by federal control experts and 21 by recreational hunters. In general, the amount of effort needed to eradicate each feral swine slowly increased …

Downed Wood Removal Effects On Survival And Site Fidelity Of Woodrats In A California Oak Woodland, Timothy J. Smyser, Michael A. Hardy, Amy J. Davis, William L. Preston, William D. Tietje

United States Department of Agriculture Wildlife Services: Staff Publications

Owing to the increasing intensity and frequency of wildfires in the western United States, the removal of woody debris (downed dead wood and snags) from fire‐prone landscapes is being evaluated for wildfire mitigation. Consequently, the study of the ecological value of coarse woody debris to sustain dependent species has become of foremost importance. From 2004–2009, we used a before‐after control‐impact (BACI) study design to assess the effects of downed wood removal on a population of big‐eared woodrats (Neotoma macrotis) in an oak woodland (Quercus spp.) in coastal‐central California, USA. Using Pollock's robust design mark‐recapture analyses (with 12 …

High Thermal Quality Rookeries Facilitate High Thermoregulatory Accuracy In Pregnant Female Rattlesnakes, Haley A. Moniz, Jack Henry Buck, Hayley L. Crowell, Scott M. Goetz, Trevor D. Ruiz, Emily N. Taylor, Scott M. Bobacks

United States Department of Agriculture Wildlife Services: Staff Publications

Temperature is a primary factor influencing organismal development, and the fluctuating daily and seasonal thermal regimes of temperate climates may challenge the ability of viviparous reptiles to optimize body temperatures during gestation. Testing how viviparous reptiles navigate highly variable thermal conditions (e.g., relatively cold nights and/or highly fluctuating temperatures) is a powerful way to understand how they use microhabitats for thermoregulatory benefits. We assessed the thermal ecology of pregnant and non-pregnant female prairie rattlesnakes (Crotalus viridis) inhabiting a high-elevation, montane shrubland in northwest Colorado throughout their short summer active season, addressing the thermal consequences of microhabitat selection with …

Characterizing Feral Swine Movement Across The Contiguous United States Using Neural Networks And Genetic Data, Rachael M. Giglio, Courtney F. Bowden, Ryan K. Brook, Antoinette J. Piaggio, Timothy J. Smyser

United States Department of Agriculture Wildlife Services: Staff Publications

Globalization has led to the frequent movement of species out of their native habitat. Some of these species become highly invasive and capable of profoundly altering invaded ecosystems. Feral swine (Sus scrofa × domesticus) are recognized as being among the most destructive invasive species, with populations established on all continents except Antarctica. Within the United States (US), feral swine are responsible for extensive crop damage, the destruction of native ecosystems, and the spread of disease. Purposeful human-mediated movement of feral swine has contributed to their rapid range expansion over the past 30 years. Patterns of deliberate introduction of …

Bayesian Integrated Species Distribution Models For Hierarchical Resource Selection By A Soaring Bird, Ryo Ogawa, Guiming Wang, L. Wes Burger, Bronson Strickland, J. Brian Davis, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Migratory birds exhibit seasonal geographic range (hereafter, range) dynamics during the annual cycle. Few studies have examined how migratory birds select their habitats for range occupancy at the species level and space use at the individual level simultaneously. We hypothesized that environmental variables directly related to fitness components would affect the range occupancy probabilities of migrants, whereas environment variables related to movements and flights would affect the space use intensities of migrants. We built Bayesian integrated species distribution models (ISDMs) to evaluate the effects of climate conditions, wind conditions, and landcover compositions on the seasonal range dynamics of American white …

Raccoon Density Estimation From Camera Traps For Raccoon Rabies Management, Amy J. Davis, Wesley C. Dixon, Richard B. Chipman, Amy T. Gilbert, Jacob E. Hill, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

Density estimation for unmarked animals is particularly challenging, yet density estimates are often necessary for effective wildlife management. Raccoons (Procyon lotor) are the primary terrestrial wildlife reservoir for Lyssavirus rabies within the United States. The raccoon rabies variant (RRVV) is actively managed at landscape scales using oral rabies vaccination (ORV) within the eastern United States. To effectively manage RRVV, it is important to know the density of raccoons to appropriately scale the density of ORV baits distributed on the landscape. We compared methods to estimate raccoon densities from camera‐trap data versus more intensive capture‐mark‐recapture (CMR) estimates across 2 …

The Effects Of Habitat Characteristics And Location On Brook Trout Size Distribution, Bryce Groves

Journal of Earth and Life Science

Adfluvial Brook Trout Salvelinus fontinalis are known to typically grow larger than riverine Brook Trout. The Kabekona River in Hubbard County, Minnesota exhibits suitable habitat for both fluvial and adfluvial Brook Trout populations. The objective of this study was to analyze the relationships between depth, stream width, canopy cover, water temperature, sediment size, and distance from Kabekona Lake on Brook Trout size distribution in the Kabekona River. Brook Trout (n=35) were angled from the Kabekona River from August 24 to September 26, 2023. Each fish was measured and released, with habitat metrics being recorded at time of release. ArcGIS was …

Paralog Switching Facilitates Diadromy: Ontogenetic, Microevolutionary And Macroevolutionary Evidence, Rebecca S. Colby, Stephen D. Mccormick, Jonathan P. Velotta, Elizabeth Jockusch, Eric T. Schultz

EEB Articles

Euryhalinity is present in diverse aquatic taxa and requires flexible osmoregulation to field the challenges posed by differing salinities. Na+, K+-ATPase (NKA) is a ubiquitous ion pump in the gills of fishes and, for some species, paralogs of the catalytic -subunit (NKA 1a and NKA 1b) exhibit reciprocal expression between fresh- and seawater, termed paralog-switching. We investigated the expression and evolution of NKA paralogs in Alewife (Alosa pseudoharengus), a euryhaline and migratory fish. Comparisons between landlocked and diadromous life history forms and migrant and pre-migrant ontogenetic stages were used to study shifts in NKA paralog expression related to freshwater or …

Impacts Of Anthropogenic Sedimentation On Shell-Bed Habitats In Lake Tanganyika, Africa, Michael Soreghan, Andrew Cohen, Michael M. Mcglue, Kevin M. Yeager, Emily Ryan, Alison Johns, Ishmael Kimirei

Earth and Environmental Sciences Faculty Publications

Lake Tanganyika, in central Africa, contains a diverse and endemic fauna under threat from global climate change, overfishing, and nearshore sediment pollution. Previous studies of sediment pollution focused justifiably on impacts along rocky shorelines where diversity is high, but Lake Tanganyika also contains widespread shelly accumulations (shell beds) unprecedented in the modern East African lakes, but where impacts are less con- strained. Here we integrate multiple datasets from three sites along the Tanzanian shoreline to explore how variation in sedimentation rates and sediment quality impacts shell-bed substrate and diversity and abundance of ostracodes and sponges across sites that exhibit varying …

Effect Of Walleye Fry Stocking On Future Gillnet Cpue, Alexander Barker

Journal of Earth and Life Science

Walleye Sanders vitreus for many states, is a key attractant of anglers from around North America. Due to immense popularity, management efforts have been conducted to maintain Walleye populations, especially in the form of stocking. The purpose of this study is to analyze the effect of Walleye fry stocking on gillnet catch per unit effort (CPUE). A total of 90 lakes were analyzed for this study within three defined regions of Minnesota, 30 from each region. The regions chosen for this study are the Minnesota Department of Natural Resources northern pike Esox lucius regulation regions which consist of the Southern, …

Landscape-Scale Epidemiological Dynamics Of Sars-Cov-2 In White-Tailed Deer, Joshua Hewitt, Grete Wilson-Henjum, Derek T. Collins, Timothy J. Linder, Julianna B. Lenoch, Jonathan D. Heale, Christopher A. Quintanal, Robert Pleszewski, Dillon S. Mcbride, Andrew S. Bowman, Jeffrey C. Chandler, Susan A. Shriner, Sarah N. Bevins, Dennis J. Kohler, Richard B. Chipman, Allen L. Gosser, David L. Bergman, Thomas J. Deliberto, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding pathogen emergence in new host species is fundamental for developing prevention and response plans for human and animal health. We leveraged a large-scale surveillance dataset coordinated by United States Department of Agriculture, Animal and Plant Health Inspection Service and State Natural Resources Agencies to quantify the outbreak dynamics of SARS-CoV-2 in North American white-tailed deer (Odocoileus virginianus; WTD) throughout its range in the United States. Local epidemics in WTD were well approximated by a single-outbreak peak followed by fade out. Outbreaks peaked early in the northeast and mid- Atlantic. Local effective reproduction ratios of SARS-CoV-2 were between …

What Is Known, Unknown, And Needed To Be Known About Damage Caused By Wild Pigs, Kurt C. Vercauteren, Kim M. Pepin, Seth M. Cook, Sophie Mckee, Abigail Pagels, Keely J. Kohen, Ingrid A. Messner, Michael P. Glow, Nathan P. Snow

United States Department of Agriculture Wildlife Services: Staff Publications

Damage assessments provide evidence for initiating and evaluating management programs that protect natural resources and human livelihoods against invasive species. Wild pigs (Sus scrofa) cause extensive damage in their native and non-native ranges, but the extent of current damage and efficacy of management of the damage (i.e., population control of wild pigs, exclusion fencing, etc.) remains poorly described. We conducted a systematic review of physical damage caused by wild pigs to summarize what is known and identify knowledge gaps for damage assessment. Wild pig damage assessments have been overwhelmingly qualitative (84% of studies) and measured differently across studies, …

Tracking Sero-Molecular Trends Of Swine Brucellosis In Hawai'i And The Central Pacific, Thi Hai Au La, Ian A. Mcmillan, Prashant Dahal, Andrew H. Burger, Mahdi Belcaid, Darrin M. Phelps, Samuel M. Goldstein, Vienna R. Brown, Michael H. Norris

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

Brucellosis is a zoonotic disease of mammals caused by bacterial species of the Brucella genus. The reservoir for disease is typically mammals, with species of Brucella found infecting amphibians, bats, and marine mammals. Brucella spp. can pass directly to humans through contact with infected animals or their products. Brucella spp. can cause chronic debilitating infections in mammals, including humans, and is associated with spontaneous abortions in infected animals, causing reduced fecundity. In Hawai‘i, terrestrial species that could harbor Brucella spp. include swine, cattle, horses, and axis deer among others. The numerous feral swine in Hawai‘i are known to carry …

Grazing Management For Livestock, Free-Roaming Horses And Burros, And Resilience, Sherman R. Swanson

Human–Wildlife Interactions

Grazing management avoids overgrazing by allocating forage for livestock on the basis of animal unit months and managing wild and free-roaming horses (Equus caballus) and burros (E. asinus) to achieve and maintain an appropriate management level (AML) for each herd. Riparian green forage and water attracts cattle (Bos taurus) and equids when upland forage is brown. Key species that focus management for resilience to weather variation, fire, and floods are preferred forage plants for cattle and horses. They include riparian stabilizers such as densely rooted sedges and deep-rooted perennial grasses in sagebrush (Artemisia …

An Effective Method For Long-Term Control Of American Bullfrogs Syntopic With Special-Status Native Amphibians In California, Usa, Jeff A. Alvarez, Jeffery T. Wilcox

Human–Wildlife Interactions

American bullfrogs (Lithobates catesbeianus) are invasive in western North America and are well established in California, USA, where they are widespread. This invasive species has been implicated in the decrease of native amphibian populations and is believed to have contributed to the decline of threatened and endangered amphibians regionally. We utilized air rifles, tin alloy pellets, and 2 shooters to systematically control L. catesbeianus in both lentic and lotic habitat types within 2 counties in California. We visited sites monthly (April through November) for approximately 8 and 14 years to lethally target and remove L. catesbeianus …

Impact Of Road Infrastructures On The Abundance Of Common Chameleon Populations, Pablo García-Quevedo, Francisco Díaz-Ruiz, Antonio Román Muñoz, Jesús Duarte, Adrián Martín-Taboada, José-María García-Carrasco, Miguel Ángel Farfán

Human–Wildlife Interactions

The common chameleon (Chamaeleo chamaeleon) is a threatened species in Spain. The loss and transformation of their traditional habitats are among the main causes of its decline. Linear infrastructures, such as roads and highways, cause direct habitat loss, roadkill, and fragmentation of populations by acting as an artificial barrier. In this study, we investigated the potential effect of 2 high-speed road infrastructures in southern Spain on local populations of common chameleons. A total of 34 grids of 1x1 km were sampled, differentiating between grids without road presence (n = 17) and grids with road presence (n …

Waterbird-Perceived Damage, Control Measures, And Economic Implications For Rice Production In The Brazilian Cerrado, Demetrio Luis Guadagnin, Alexandre Afonso Meyer, João Augusto Rossi Borges, Fernanda Maia Justo

Human–Wildlife Interactions

Waterbirds have the potential to inflict economic damage to crops. However, is rice (Oryza sativa) production in the Brazilian Cerrado significantly affected by waterbirds? This study aimed to assess the extent of waterbird damage on irrigated rice production in Central Brazil. We conducted surveys of waterbird populations in rice agroecosystem habitats throughout the cultivation cycle and analyzed the expenses associated with waterbird-induced yield losses and the control measures employed by farmers. The 2 most prevalent waterbird species observed were Dendrocygna viduatta and D. autumnalis, comprising 68.6% of all recorded waterbirds. These species were more frequently encountered and …