Natural Resources and Conservation Commons^™

Scavenging In The Anthropocene: Human Impact Drives Vertebrate Scavenger Species Richness At A Global Scale, Esther Sebastián‐González, Jomar Magalhães Barbosa, Juan M. Pérez‐García, Zebensui Morales‐Reyes, Francisco Botella, Pedro P. Olea, Patricia Mateo‐Tomás, Marcos Moleón, Fernando Hiraldo, Eneko Arrondo, José A. Donázar, Ainara Cortés‐Avizanda, Nuria Selva, Sergio A. Lambertucci, Aishwarya Bhattacharjee, Alexis Brewer, Erin Abernethy, Olin E. Rhodes Jr., Kelsey Turner, James C. Beasley, Travis L. Devault, Andrés Ordiz, Camilla Wikenros, Barbara Zimmermann, Petter Wabakken, Christopher C. Wilmers, Justine A. Smith, Corinne J. Kendall, Darcy Ogada, Evan R. Buechley, Ethan Frehner, Maximilian L. Allen, Heiko U. Wittmer, James R.A. Butler, Johan T. Du Toit, John Read, David Wilson, Klemen Jerina, Miha Krofel, Rich Kostecke, Richard Inger, Arockianathan Samson, Lara Naves‐Alegre, José A. Sánchez‐Zapata

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large‐scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion‐consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using …

The Economic Impacts Of Blackbird (Icteridae) Damage To Sunflower In The Usa, Karina Ernst, Julie Elser, George Linz, Hans Kandel, Jason Holderieath, Samantha Degroot, Steven Shwiff, Stephanie Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Blackbird (Icteridae) damage to ripening sunflower (Helianthus annuus L.) has been a persistent economic issue in the USA for the last five decades. To quantify losses, we surveyed blackbird damage from 2001 to 2013 (excluding 2004) to physiologically mature sunflower in eight states: North Dakota, South Dakota, Texas, Nebraska, Minnesota, Colorado, Kansas, and Vermont.

RESULTS:We pooled data gathered during the most recent 5 years (2009 to 2013) of the survey and found losses averaged $US2.5 million and $US11.3 million for confectionery and oilseed hybrids, respectively. Three states, North Dakota, South Dakota, and Nebraska, had sufficient acreage and bird damage …

Habitat Selection By American Beaverat Multiple Spatial Scales, Guiming Wang, Lance F. Mcclintic, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Semiaquatic mammals require both aquatic and terrestrial habitats, particularly interfaces between the two habitats. As ecosystem engineers, American beaver (Castor canadensis) consume and fell a great amount of deciduous trees. We tested the prediction that open water and amounts of food resources, including hardwood forests (i.e., deciduous trees as the dominant form of vegetation), herbaceous and woody wetlands, and shrubs, would influence the second-order habitat selection (i.e., placing home ranges on the landscape) by American beaver, whereas the third-order habitat selection of American beaver would be associated with woody wetland and shrub edges. We investigated hierarchical habitat selection by …

Epidemic Growth Rates And Host Movement Patterns Shape Management Performance For Pathogen Spillover At The Wildlife–Livestock Interface, Kezia R. Manlove, Laura M. Sampson, Benny Borremans, E. Frances Cassirer, Ryan S. Miller, Kim M. Pepin, Thomas E. Besser, Paul C. Cross

United States Department of Agriculture Wildlife Services: Staff Publications

Managing pathogen spillover at the wildlife–livestock interface is a key step towards improving global animal health, food security and wildlife conservation. However, predicting the effectiveness of management actions across host–pathogen systems with different life histories is an on-going challenge since data on intervention effectiveness are expensive to collect and results are system-specific.We developed a simulation model to explore how the efficacies of different management strategies vary according to host movement patterns and epidemic growth rates. The model suggested that fast-growing, fast-moving epidemics like avian influenza were best-managed with actions like biosecurity or containment, which limited and localized overall spillover risk. …

Resource Assessment Report Western Rock Lobster Resource Of Western Australia. Addendum 1, Simon De Lestang, Jason How, Nick Caputi

WA Marine Stewardship Council report series

The West Coast Rock Lobster Fishery was certified under the Marine Stewardship Council (MSC) standard in 2000, and was the first fishery in the world to be MSC certified. Since then it has successfully been re-accredited in 2006, 2012 and 2017. This document provides an update on changes to the fishery for annual audits by the MSC certification body and the annual stock assessment update for quota setting of the western rock lobster resource.

Board Invited Review: Prospects For Improving Management Of Animal Disease Introductions Using Disease-Dynamic Models, Ryan S. Miller, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Management and policy decisions are continually made to mitigate disease introductions in animal populations despite often limited surveillance data or knowledge of disease transmission processes. Science-based management is broadly recognized as leading to more effective decisions yet application of models to actively guide disease surveillance and mitigate risks remains limited. Disease-dynamic models are an efficient method of providing information for management decisions because of their ability to integrate and evaluate multiple, complex processes simultaneously while accounting for uncertainty common in animal diseases. Here we review disease introduction pathways and transmission processes crucial for informing disease management and models at the …

Mammals Of The Northern Andes: An Analysis Of Camera Trap Data And Observation In Angochagua, Ecuador, Risa Berman

Independent Study Project (ISP) Collection

The high Andes of Ecuador are home to a diverse community of mammals, many of which are threatened. These include the Andean bear, Andean fox, puma, and mountain tapir. This study used camera traps, direct observation, and indirect observation over three weeks to monitor the wildlife in the mountains of the Parroquia of Angochagua. The five species observed during this period were Andean bear, Andean fox, dog, mountain paca, and mouse. While this short study did not completely survey the mammalian community of the area, it confirmed the presence, diet, sociality, temporal habits, elevational range, and habitat preferences of the …

Improving Risk Assessment Of The Emergence Of Novel Influenza A Viruses By Incorporating Environmental Surveillance, Kim M. Pepin, Matthew W. Hopken, Susan A. Shriner, Erica Spackman, Zaid Abdo, Colin Parrish, Steven Steven, James O. Lloyd-Smith, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Reassortment is an evolutionary mechanism by which influenza A viruses (IAV) generate genetic novelty. Reassortment is an important driver of host jumps and is widespread according to retrospective surveillance studies.However, predicting the epidemiological risk of reassortant emergence in novel hosts from surveillance data remains challenging. IAV strains persist and cooccur in the environment, promoting co-infection during environmental transmission. These conditions offer opportunity to understand reassortant emergence in reservoir and spillover hosts. Specifically, environmental RNA could provide rich information for understanding the evolutionary ecology of segmented viruses, and transform our ability to quantify epidemiological risk to spillover hosts. However, significant challenges …

Substantial Red Wolf Genetic Ancestry Persists In Wild Canids Of Southwestern Louisiana, Jennifer R. Adams, John J. Cox, Lisette P. Waits

Forestry and Natural Resources Faculty Publications

Concerns over red wolf (Canis rufus) extinction caused by hybridization with coyotes (C. latrans) led to the capture and removal of remnant wild wolves from southwestern Louisiana and southeastern Texas, United States, during the 1970s. Here we show that despite decades of unmitigated hybridization, and declaration of endangered red wolves as functionally extinct in the wild, red wolf mitochondrial or nuclear DNA ancestry persists in ∼55% of contemporary wild canids sampled in southwestern Louisiana. Surprisingly, one individual had 78–100% red wolf ancestry, which is within the range for 75% red wolf, red wolf backcross, or putative …

Spatial And Temporal Variability In Post-Larval Yellow Perch Density, Steve Hauschildt

Biology Graduate Theses

Yellow Perch Perca flavescens are important as forage for other species and for sport fishing in many northern lakes. However, estimating post-larval Yellow Perch populations can be difficult because of many environmental factors that cause unexplained variation. The objective of this study was to help reduce unexplained variation by determining a post-larval Yellow Perch population density estimate on Blackduck Lake, MN, provide guidance to help determine the number of trawls required for trawling-based recruitment indices to achieve varying levels of precision, and test for the effects of wind speed and direction on post-larval Yellow Perch spatial variability. This study estimated …

Individual-Level Antibody Dynamics Reveal Potential Drivers Of Influenza A Seasonality In Wild Pig Populations, Kim M. Pepin, Kerri Pedersen, Xiu-Feng Wan, Fred L. Cunningham, Colleen T. Webb, Mark Q. Wilber

United States Department of Agriculture Wildlife Services: Staff Publications

Swine are important in the ecology of influenza A virus (IAV) globally. Understanding the ecological role of wild pigs in IAV ecology has been limited because surveillance in wild pigs is often for antibodies (serosurveillance) rather than IAVs, as in humans and domestic swine. As IAV antibodies can persist long after an infection, serosurveillance data are not necessarily indicative of current infection risk. However, antibody responses to IAV infections cause a predictable antibody response, thus time of infection can be inferred from antibody levels in serological samples, enabling identification of risk factors of infection at estimated times of infection. Recent …

Estimating The Use Of Public Lands: Integrated Modeling Of Open Populations With Convolution Likelihood Ecological Abundance Regression, Lutz F. Gruber, Erica F. Stuber, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We present an integrated open population model where the population dynamics are defined by a differential equation, and the related statistical model utilizes a Poisson binomial convolution likelihood. Key advantages of the proposed approach over existing open population models include the flexibility to predict related, but unobserved quantities such as total immigration or emigration over a specified time period, and more computationally efficient posterior simulation by elimination of the need to explicitly simulate latent immigration and emigration. The viability of the proposed method is shown in an in-depth analysis of outdoor recreation participation on public lands, where the surveyed populations …

Using Dna To Identify The Source Of Invasive Mongooses, Herpestes Auropunctatus (Carnivora: Herpestidae) Captured On Kaua‘I, Hawaiian Islands, Darren J. Wostenberg, Matthew W. Hopken, Aaron B. Shiels, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Two small Indian mongooses (Herpestes auropunctatus) were live-captured in 2012 at separate locations on the Hawaiian Island of Kaua'i, which was previously considered to be free of this invasive species. Genotypes from these two individuals were compared to genotypes of H. auropunctatus from the islands of Hawai'i (n =39), O'ahu (n =91), Maui (n = 39), and Moloka'i (n = 19) to determine the island of origin of the Kaua'i individuals. Genotypes were generated from each individual using five microsatellite loci. Genetic clustering was estimated by Bayesian inference of spatial clustering of individuals and …

Reducing Prairie Dog Populations And Damage By Castration Of Dominant Males, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus) occur widely across the prairie states of North America. They compete with livestock for forage, transmit plague, and damage lawns, landscaping, and property. Interest in non-lethal methods, such as immunocontraception, is growing; however, reductions in the population due to contraception may be offset by increases in survival because adults and yearlings are not subject to the energetic demands of reproduction, and lower densities may increase the amount of resources available to growing offspring. Surgical sterilization provides a means for modeling these effects. Thus, we castrated males prior to the 1998 breeding season to simulate the …

The Future Of Recreational Fisheries: Advances In Science, Monitoring, Management, And Practice, Jacob W. Brownscombe, Kieran Hyder, Warren Potts, Kyle L. Wilson, Kevin L. Pope, Andy J. Danylchuk, Steven J. Cooke, Adrian Clarke, Robert Arlinghaus, John R. Post

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries (RF) are complex social-ecological systems that play an important role in aquatic environments while generating significant social and economic benefits around the world. The nature of RF is diverse and rapidly evolving, including the participants, their priorities and behaviors, and the related ecological impacts and social and economic benefits. RF can lead to negative ecological impacts, particularly through overexploitation of fish populations and spread of non-native species and genotypes through stocking. Hence, careful management and monitoring of RF is essential to sustain these ecologically and socioeconomically important resources. This special issue on recreational fisheries contains diverse research, syntheses, …

Advancing Urban Wildlife Research Through A Multi-City Collaboration, Seth B. Magle, Mason Fidino, Elizabeth W. Lehrer, Travis Gallo, Matthew P. Mulligan, María Jazmín Ríos, Adam A. Ahlers, Julia L. Angstmann, Amy Belaire, Barbara Dugelby, Ashley Gramza, Laurel Hartley, Brandon Macdougall, Travis J. Ryan, Carmen M. Salsbury, Heather Sander, Christopher Schell, Kelly Simon, Sarah St. Onge, David Drake

Scholarship and Professional Work - LAS

Research on urban wildlife can help promote coexistence and guide future interactions between humans and wildlife in developed regions, but most such investigations are limited to short-term, single-species studies, typically conducted within a single city. This restricted focus prevents scientists from recognizing global patterns and first principles regarding urban wildlife behavior and ecol- ogy. To overcome these limitations, we have designed a pioneering research network, the Urban Wildlife Information Network (UWIN), whereby partners collaborate across several cities to systematically collect data to populate long-term datasets on multiple species in urban areas. Data collected via UWIN support analyses that will enable …

Age-0 Walleye Sander Vitreus Display Length-Dependent Diet Shift To Piscivory, Christopher S. Uphoff, Casey W. Schoenebeck, Keith D. Koupal, Kevin L. Pope, W. Wyatt Hoback

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The ontogenetic diet shift to piscivory can be energetically beneficial for fish growth and allows larger, more energetically profitable prey to be consumed. A shift to piscivory may be easier for longer individuals within a cohort due to larger gape size, and an early shift is likely advantageous, potentially leading to increased growth rates and survival. Such length-dependent ontogenetic diet shifts may explain the intracohort variability in length that is common for age-0 walleye (Sander vitreus). The objectives of this study were to describe seasonal intracohort variability in length, identify the timing of the shift to piscivory and …

Ecosystem Size Predicts Social-Ecological Dynamics, Mark A. Kaemingk, Christopher J. Chizinski, Craig R. Allen, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries are complex adaptive systems that are inherently difficult to manage because of heterogeneous user groups (consumptive vs. nonconsumptive) that use patchily distributed resources on the landscape (lakes, rivers, coastlines). There is a need to identify which system components can effectively predict and be used to manage nonlinear and cross-scale dynamics within these systems. We examine how ecosystem size or water body size can be used to explain complicated and elusive angler-resource dynamics in recreational fisheries. Water body size determined angler behavior among 48 Nebraska, U.S.A. water bodies during an 11- year study. Angler behavior was often unique and …

River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2019, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Gerry Pinto, Brian P. Zoellner, Christopher Baynard, Charles Closmann, Nisse Goldberg, Scott F. Jones, William Penwell, Radha Pyati, Adam E. Rosenblatt, Gretchen Bielmyer-Fraser

State of the River Report

No abstract provided.

Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb

Journal of Earth and Life Science

The Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were …

Cause‐Specific Mortality Of The World’S Terrestrial Vertebrates, Jacob E. Hill, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Aim: Vertebrates are declining worldwide, yet a comprehensive examination of the sources of mortality is lacking. We conducted a global synthesis of terrestrial vertebrate cause‐specific mortality to compare the sources of mortality across taxa and determine predictors of susceptibility to these sources of mortality.

Location: Worldwide.

Time period: 1970–2018.

Major taxa studied: Mammals, birds, reptiles and amphibians.

Methods: We searched for studies that used telemetry to determine the cause of death of terrestrial vertebrates. We determined whether each mortality was caused by anthropogenic or natural sources and further classified mortalities within these two categories (e.g. harvest, vehicle collision and predation). …

Feral Swine Harming Insular Sea Turtle Reproduction: The Origin, Impacts, Behavior And Elimination Of An Invasive Species, Richard M. Engeman, Robert W. Byrd, Jamie Dozier, Mark A. Mcalister, James O. Edens, Elizabeth M. Kierepka, Timothy J. Smyser, Noel Myers

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine are among the world's most destructive invasive species wherever they are found, with translocations figuring prominently in their range expansions. In contrast, sea turtles are beloved species that are listed as threatened or endangered throughout the world and are the focus of intense conservation efforts. Nest predation by feral swine severely harms sea turtle reproduction in many locations around the world. Here we quantify and economically assess feral swine nest predation at North Island, South Carolina, an important loggerhead sea turtle nesting beach. Feral swine depredation of North Island sea turtle nests was first detected in 2005, with …

A Bioeconomic Model For The Optimization Of Local Canine Rabies Control, Aaron Anderson, Johann Kotze, Stephanie A. Shwiff, Brody Hatch, Chris Slootmaker, Anne Conan, Darryn Knobel, Louis H. Nel

United States Department of Agriculture Wildlife Services: Staff Publications

We present a new modeling tool that can be used to maximize the impact of canine rabies management resources that are available at the local level. The model is accessible through a web-based interface that allows for flexibility in the management strategies that can be investigated. Rabies vaccination, sterilization, chemo-contraception, and euthanasia can be specified and limited to specific demographic groups. Additionally, we allowed for considerable complexity in the specification of management costs. In many areas, the costs of contacting additional dogs increases as management effort increases, and this can have important strategic implications. We illustrated the application of the …

No Detection Of Brodifacoum Residues In The Marine And Terrestrial Food Web Three Years After Rat Eradication At Palmyra Atoll, Central Pacific, A. Wegmann, G. Howald, S. Kropidlowski, N. Holmes, A.B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive alien species represent one of the greatest threats to native plants and animals on islands. Rats (Rattus spp.) have invaded most of the world’s oceanic islands, causing lasting or irreversible damage to ecosystems and biodiversity. To counter this threat, techniques to eradicate invasive rats from islands have been developed and applied across the globe. Eradication of alien rats from large or complex island ecosystems has only been successful with the use of bait containing a rodenticide. While effective at eradicating rats from islands, rodenticide can persist in the ecosystem longer than the time required to eradicate the target rat …

Ecological Functions Of Vertebrate Scavenging, James C. Beasley, Zachary H. Olson, Nuria Selva, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

The role of vertebrate scavenging in food web dynamics has historically been minimalized and portrayed as the activity of a select group of obligate scavengers (e.g., vultures), with a simplistic linkage between carrion and detritivores in food webs. Research in the last few decades, however, has revealed that the role of carrion in food web dynamics is severely underestimated, highly complex, and pervasive among ecosystems across the globe (DeVault et al. 2003; Selva and Fortuna 2007; Wilson and Wolkovich 2011). Such observations have led to a surge in research interest in scavenging ecology that continues to reveal new information …

Mind The Gap: Experimental Tests To Improve Efficacy Of Fladry For Nonlethal Management Of Coyotes, Julie K. Young, John Draper, Stewart Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) are the top predator of livestock in the contiguous United States. Developing more effective nonlethal tools to prevent coyote depredation will facilitate coexistence between livestock producers and coyotes. Fladry is a nonlethal deterrent designed to defend livestock by creating a visual barrier to wolves (C. lupus). Fladry may also be effective with coyotes, but large gap spacing between flags may reduce its efficacy. To address this issue, we performed 2 experiments on captive coyotes using fladry modified to reduce gap spacing at the U.S. Department of Agriculture, Predator Research Facility in Millville, Utah, USA, during 2015–2016 and …

What Are The Transmission Mechanisms Of Influenza A Viruses In Wild Mammals?, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

Some influenza A viruses (IAVs) represent serious potential threats to public and agricultural health, with 3 notable examples from the past decade. During 2009, a novel H1N1 IAV (A[H1N1]pdm09), which was first detected in the United States, spread rapidly throughout many regions of the world. In the United States alone, the Centers for Disease Control and Prevention estimated that >60 million human cases were associated with this emergent and pandemic virus. During 2013, a novel H7N9 avian-origin IAV (Asian lineage avian influenza A[H7N9] virus) was first detected in China. This virus not only cost the poultry industry more than $1 …

Analysis Of Iophenoxic Acid Analogues In Small Indian Mongoose (Herpestes Auropunctatus) Sera For Use As An Oral Rabies Vaccination Biological Marker, Are R. Berentsen, Robert T. Sugihara, Cynthia G. Payne, Israel Leinbach, Steven F. Volker, Ad Vos, Steffen Ortmann, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Herpestes auropunctatus) is a reservoir of rabies virus (RABV) in Puerto Rico and comprises over 70% of animal rabies cases reported annually. The control of RABV circulation in wildlife reservoirs is typically accomplished by a strategy of oral rabies vaccination (ORV). Currently no wildlife ORV program exists in Puerto Rico. Research into oral rabies vaccines and various bait types for mongooses has been conducted with promising results. Monitoring the success of ORV relies on estimating bait uptake by target species, which typically involves evaluating a change in RABV neutralizing antibodies (RVNA) post vaccination. This …

Carrion Availability In Space And Time, Marcos Moleón, Nuria Selva, David M. Bailey, David M. Bailey, Ainara Cortés-Avizanda, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

Availability of carrion to scavengers is a central issue in carrion ecology and management, and is crucial for understanding the evolution of scavenging behaviour. Compared to live animals, their carcasses are relatively unpredictable in space and time in natural conditions, with a few exceptions (see below, especially Sect. “Carrion Exchange at the Terrestrial-Aquatic Interface”). Carrion is also an ephemeral food resource due to the action of a plethora of consumers, from microorganisms to large vertebrates, as well as to desiccation (i.e., loss of water content; DeVault et al. 2003; Beasley et al. 2012; Barton et al. 2013; Moleón et …

Comparing Live-Capture Methods For Nutria: Single- Versus Multiple-Capture Cage Traps, Trevor R. Sheffels, Mark D. Sytsma, Jacoby Carter, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Herbivory and burrowing by nutria (Myocastor coypus) cause substantial ecological and economic damage. Trapping is a common, effective practice for reducing nutria damage; however, trapping approaches must continually be adapted to keep pace with evolving animal welfare and ethical issues and to more effectively target pest species of interest. Our objective was to evaluate the efficacy of 2 nonlethal trap types for nutria: single-capture (SCT) and multi-capture (MCT) cage traps. We established 3 MCTs and 3 SCTs at each of 7 sites on a 10,500-ha mixed-use island located 15 km northwest of Portland, Oregon, USA. We pre-baited using carrots, apples, …