Life Sciences Commons^™

Estimating Stand-Level Economic Impacts Of Black Bear Damage To Intensively Managed Forests, Kristina N. Kline, Jimmy D. Taylor, Anita T. Morzillo

United States Department of Agriculture Wildlife Services: Staff Publications

Black bears (Ursus americanus Pallas, 1780) peel conifers in early spring to forage on energy-rich vascular tissues, resulting in damage to timber stands. The objective of our study was to develop and demonstrate a conceptual framework and methods for estimating stand-level volume and economic losses from black bear damage. We created tree lists from surveys of healthy and bear-damaged trees in timber stands of western Washington and Oregon. The forest growth model Forest Vegetation Simulator (FVS) was used to project stand volume under two damage scenarios and an undamaged scenario. One damage scenario (salvage) accounted for mortality and volume …

A Conceptual Model For The Integration Of Social And Ecological Information To Understand Human-Wildlife Interactions, Stacy A. Lischka, Tara L. Teel, Heather E. Johnson, Sarah E. Reed, Stewart Breck, Andrew Don Carlos, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

There is growing recognition that interdisciplinary approaches that account for both ecological and social processes are necessary to successfully address human-wildlife interactions. However, such approaches are hindered by challenges in aligning data types, communicating across disciplines, and applying social science information to conservation actions. To meet these challenges, we propose a conceptual model that adopts a social-ecological systems approach and integrates social and ecological theory to identify the multiple, nested levels of influence on both human and animal behavior. By accounting for a diverse array of influences and feedback mechanisms between social and ecological systems, this model fulfills a need …

Seasonal Variation In Preference Dictates Space Use In An Invasive Generalist, Kelsey E. Paolini, Bronson K. Strickland, Jessica L. Tegt, Kurt C. Vercauteren, Garrett M. Street

United States Department of Agriculture Wildlife Services: Staff Publications

The spatiotemporal distribution of resources is a critical component of realized animal distributions.

In agricultural landscapes, space use by generalist consumers is influenced by ephemeral resource availability that may produce behavioral differences across agricultural seasons, resulting in economic and production consequences and increased human-wildlife conflict. Our objective was to assess changes in habitat selection across seasons in an invasive generalist omnivore (feral pigs, Sus scrofa). Hypothesizing that pig space use is primarily driven by forage availability, we predicted strong selection for the most nutritionally beneficial crops and resource types as agricultural seasons progressed. We deployed GPS collars on 13 …

Habitat Type And Structure Affect Trap Capture Success Of An Invasive Snake Across Variable Densities, Melia G. Nafus, Amy A. Yackel Adams, Page E. Klug, Gordon H. Rodda

United States Department of Agriculture Wildlife Services: Staff Publications

Detection represents an important limitation of accurately estimating population size, abundance, and habitat suitability for wildlife, which can be especially true for cryptic animals. Moreover, for reptiles, juveniles are often less likely to be detected than later life stages. In the case of invasive species, preventing false negatives early in the invasion process can be critical for improving outcomes of control measures. We evaluated habitat structure in relation to catch per unit effort (CPUE) and mean size of trapped invasive brown treesnakes (Boiga irregularis) on Guam. We used a 5-ha enclosure containing a known, closed population of brown treesnakes to …

Impacts Of Biomass Production At Civil Airports On Grassland Bird Conservation And Aviation Strike Risk, Tara J. Conkling, Jerrold L. Belant, Travis L. Devault, James A. Martin

United States Department of Agriculture Wildlife Services: Staff Publications

Growing concerns about climate change, foreign oil dependency, and environmental quality have fostered interest in perennial native grasses (e.g., switchgrass [Panicum virgatum]) for bioenergy production while also maintaining biodiversity and ecosystem function. However, biomass cultivation in marginal landscapes such as airport grasslands may have detrimental effects on aviation safety as well as conservation efforts for grassland birds. In 2011–2013, we investigated effects of vegetation composition and harvest frequency on seasonal species richness and habitat use of grassland birds and modeled relative abundance, aviation risk, and conservation value of birds associated with biomass crops. Avian relative abundance was greater …

Experimental Tests Of Nonsurgical Reproductive Inhibitors To Prevent Coyote Reproduction, Julie K. Young, Marjorie J. Macgregor, Eric M. Gese, Douglas C. Eckery

United States Department of Agriculture Wildlife Services: Staff Publications

Sterilization is an effective nonlethal tool to reduce livestock depredation by coyotes (Canis latrans) because adults without pups to provision are less likely to kill livestock. Surgical sterilization is costly and invasive, so identifying nonsurgical methods for canids that allow wide-scale application is important. We conducted a preliminary assessment of 2 types of reproductive inhibitors (gonadotropin releasing hormone [GnRH] vaccine and deslorelin, a GnRH agonist) on coyote reproductive capabilities. We treated captive coyotes with a GnRH vaccine (n = 6 males, n = 6 females) or deslorelin (n = 6 males), measured number of litters and …

Genetic Evidence Supports Sporadic And Independent Introductions Of Subtype H5 Low Pathogenic Avian Influenza A Viruses From Wild Birds To Domestic Poultry In North America, Lei Li, Andrew S. Bowman, Thomas J. Deliberto, Mary L. Killian, Scott Krauss, Jacqueline M. Nolting, Mia Kim Torchetti, Andrew M. Ramey, Andrew B. Reeves, David E. Stallknecht, Richard J. Webby, Xiu-Feng Wan

United States Department of Agriculture Wildlife Services: Staff Publications

Wild-bird origin influenza A viruses (IAVs or avian influenza) have led to sporadic outbreaks among domestic poultry in the United States and Canada, resulting in economic losses through the implementation of costly containment practices and destruction of birds. We used evolutionary analyses of virus sequence data to determine that 78 H5 low-pathogenic avian influenza viruses (LPAIVs) isolated from domestic poultry in the United States and Canada during 2001 to 2017 resulted from 18 independent virus introductions from wild birds. Within the wild-bird reservoir, the hemagglutinin gene segments of H5 LPAIVs exist primarily as two cocirculating genetic sublineages, and our findings …

Raccoon (Procyon Lotor) Biomarker And Rabies Antibody Response To Varying Oral Rabies Vaccine Bait Densities In Northwestern Pennsylvania, Kerri Pedersen, Brandon S. Schmit, Thomas J. Deliberto, Jason R. Suckow, Amy J. Davis, Dennis Slate, Richard B. Chipman, Robert L. Hale, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Distribution of oral rabies vaccine baits has been used as a strategy for managing rabies in the United States since the 1990s. Since that time, efforts have been made to improve baiting strategies with a focus on bait density to maximize both efficiency and cost effectiveness. An optimal rabies management strategy includes a vaccine bait preferred by the target species that is distributed at the minimal density needed to achieve population immunity to prevent rabies spread. The purpose of our pilot study was to examine the effect of 75, 150, and 300 baits/km2 vaccine bait densities on rabies virus neutralizing …

Feral Swine Sus Scrofa: A New Threat To The Remaining Breeding Wetlands Of The Vulnerable Reticulated Flatwoods Salamander Ambystoma Bishopi, Kelly C. Jones, Thomas A. Gorman, Brandon K. Rincon, John Allen, Carola A. Haas, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine Sus scrofa have been implicated as a major threat to sensitive habitats and ecosystems as well as threatened wildlife. Nevertheless, direct and indirect impacts on threatened species (especially small, fossorial species) are not well documented. The decline of the U.S. federally endangered reticulated flatwoods salamander Ambystoma bishopi, categorized as Vulnerable on the IUCN Red List, has been rapid and there are few remaining breeding locations for this species. The flatwoods salamander depends on complex herbaceous vegetation in all life stages, including eggs, larvae and adults. Historically sets of hog tracks have been observed only occasionally in the …

Sharing An Environment With Sick Conspecifics Alters Odors Of Healthy Animals, Stephanie S. Gervasi, Maryanne Opiekun, Talia Martin, Gary K. Beauchamp, Bruce A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

Body odors change with health status and the odors of sick animals can induce avoidance behaviors in healthy conspecifics. Exposure to sickness odors might also alter the physiology of healthy conspecifics and modify the odors they produce. We hypothesized that exposure to odors of sick (but non-infectious) animals would alter the odors of healthy cagemates. To induce sickness, we injected mice with a bacterial endotoxin, lipopolysaccharide. We used behavioral odor discrimination assays and analytical chemistry techniques followed by predictive classification modeling to ask about differences in volatile odorants produced by two types of healthy mice: those cohoused with healthy conspecifics …

Human–Black Bear Conflicts, Carl W. Lackey, Stewart W. Breck, Brian F. Wakeling, Bryant White

United States Department of Agriculture Wildlife Services: Staff Publications

Most human–black bear (Ursus americanus) conflict occurs when people make anthropogenic foods like garbage, dog food, domestic poultry, or fruit trees available to bears. Bears change their behavior to take advantage of these resources and may damage property or cause public safety concerns in the process. Managers are often forced to focus efforts on reactive non-lethal and lethal bear management techniques to solve immediate problems, which do little to address root causes of human–bear conflict. As long as bears find easy access to garbage, bird feeders, urban fruit trees, and other food subsidies, conflicts are likely to continue. …

Trace Element Concentrations In The Small Indian Mongoose (Herpestes Auropunctatus) From Hawaii, Usa, Sawako Horai, Yusuke Nakashima, Kanae Nawada, Izumi Watanabe, Tatsuya Kunisue, Shintaro Abe, Fumio Yamada, Robert Sugihara

United States Department of Agriculture Wildlife Services: Staff Publications

Concentrations of 26 trace elements including essential (Mg, Ca, Cr, V, Mn, Fe, Co, Ni, Cu, Zn, Se, Sr and Mo) and toxic (As, Cd and Pb), were determined in the liver, kidney, brain, hair, muscle, and stomach contents of the small Indian mongooses inhabiting eight areas on three Hawaiian Islands, Oahu, Maui and Hawaii. There were significant differences in concentrations of some metals among the habitats. Cadmium concentrations in mongooses from the macadamia nut orchards on Island of Hawaii were relatively higher than those in populations from other seven areas. Lead concentrations in mongooses from the Ukumehame firing range …

Estimating The Economic Impact Of Canine Rabies To Viet Nam 2005–2014, Stephanie A. Shwiff, Vienna R. Brown, Thu Trang Dao, Julie Elser, Hoang Xuan Trung, Nguyen Ngoc Tien, Nguyen Thi Huong, Nguyen Thi Thanh Huong, Arthorn Riewpaiboon, Karina Ernst, Steven Shwiff, David Payne

United States Department of Agriculture Wildlife Services: Staff Publications

The global economic impact of canine rabies has been estimated by several studies. Asia bears a disproportionate burden of this zoonosis due to high levels of human deaths and rates of post-exposure prophylaxis (PEP), but low investment in preventative dog vaccination. The same factors that cause rabies to burden much of Asia are also present in Viet Nam. This study estimated the economic burden of canine rabies in a societal perspective including direct and indirect cost of rabies in dogs, livestock, and humans. Using data collected from personal interviews, published literature, published and supplementary reports, and primary data collection, we …

Fertility Control For Managing Free-Roaming Feral Cattle In Hong Kong, Giovanna Massei, Ka-Kei Koon, Siu-Iun Law, Matt Gomm, Darcy S. O. Mora, Rebecca Callaby, Kate Palphramand, Douglas C. Eckery

United States Department of Agriculture Wildlife Services: Staff Publications

Human-wildlife conflicts are increasing worldwide. For instance, growing numbers of free-roaming feral cattle in Hong Kong are causing traffic accidents and damaging crops. Public antipathy towards lethal methods to manage wildlife has promoted research into alternative options, such as fertility control. The aims of this study were to assess the potential side effects and effectiveness of the injectable immunocontraceptive vaccine GonaCon on free-roaming feral cattle in Hong Kong. Sixty female cattle were captured and randomly assigned to treatment or control groups. Treatment animals were administered one dose of GonaCon, followed by a booster dose 3–6 months later. Control animals were …

Plumage Changes In Double-Crested Cormorants (Phalacrocorax Auritus) Within The Breeding Season: The Risks Of Aging By Plumage, Jennifer E. Chastant, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

Scant attention has been given to the molting patterns of known-age Double-crested Cormorants (Phalacrocorax auritus). In general, subadult individuals are identified with a tan, buffy or mottled chest, and adults are identified with a black chest. While studying Double-crested Cormorant population dynamics in Ontario, Canada, with known-age birds, it was noted that the plumage of many (> 75%) breeding adults changed from black to heavily mottled during the course of the breeding season. No pattern with age was observed; plumage changed in equal proportions for all ages from 2-year-olds to 7-year-olds. A similar but reverse pattern has been …

Operationalizing Resilience For Conservation Objectives: The 4s’S, Clare E. Aslan, Brian Petersen, Aaron B. Shiels, William Haines, Christina T. Lang

United States Department of Agriculture Wildlife Services: Staff Publications

Although resilience thinking is increasingly popular and attractive among restoration practitioners, it carries an abstract quality that hinders effective application. Because resilience and its components are defined differently in social and ecological contexts, individual managers or stakeholders may disagree on the definition of a system’s state, occurrence of a state change, preferred state characteristics, and appropriate methods to achieve success. Nevertheless, incentives and mandates often force managers to demonstrate how their work enhances resilience. Unclear or conflicting definitions can lead to ineffective or even detrimental decision-making in the name of resilience; essentially, any convenient action can be touted as resilience-enhancing …

Evaluating Lethal And Nonlethal Management Options For Urban Coyotes, Stewart W. Breck, Sharon A. Poessel, Mary Ann Bonnell

United States Department of Agriculture Wildlife Services: Staff Publications

Human–coyote (Canis latrans) conflict in urban environments is a growing issue in cities throughout the United States, with the primary problem being the development of problem individuals that are overly bold and aggressive with people and pets. Little research has focused on management options to deal with this conflict. We better define lethal and nonlethal management strategies associated with proactive and reactive management of coyotes with an emphasis on management of problem individuals. We then provide data from research in the Denver Metropolitan Area (DMA), Colorado, USA that focused on reactive lethal removal of problem coyotes and reactive …

Using Resident-Based Hazing Programs To Reduce Human–Coyote Conflicts In Urban Environments, Mary Ann Bonnell, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

The concept of hazing (aversive conditioning) is often promoted as a tool for reducing human–coyote (Canis latrans) conflicts in urban environments. Little scientific evidence exists on the effectiveness of hazing, particularly hazing applied by residents (i.e., community-level hazing). Wildlife professionals question if residents will properly and consistently apply hazing techniques and if hazing impacts coyote behavior over short- and long-term periods. We describe 2 separate efforts designed to encourage residents to haze coyotes in the Denver Metro Area, Colorado, USA: a citizen science program and an open space hazing trial. Both efforts were intended to be management techniques …

Double-Crested Cormorants: Too Much Of A Good Thing?, Brian S. Dorr, David G. Fielder

United States Department of Agriculture Wildlife Services: Staff Publications

For centuries, people have viewed double-crested cormorants Phalacrocorax auritus negatively, and human persecution coupled with environmental contamination severely reduced numbers of cormorants throughout North America. Shifts in paradigms for management of our natural resources resulted in reductions in environmental contaminants and regulatory protection of cormorants, allowing for an amazing population resurgence of this adaptable fish-eating bird. However, for cormorants, as with some other native wildlife species the populations of which have rebounded due to conservation efforts, there have been cormorant– societal conflicts with respect to commercial and natural resources such as aquaculture and sport fisheries. Increasing resource conflicts caused cormorants …

Clearing Muddied Waters: Capture Of Environmental Dna From Turbid Waters, Kelly E. Williams, Kathryn P. Huyvaert, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the differences in efficiencies of various methods to concentrate, extract, and amplify environmental DNA (eDNA) is vital for best performance of eDNA detection. Aquatic systems vary in characteristics such as turbidity, eDNA concentration, and inhibitor load, thus affecting eDNA capture efficiency. Application of eDNA techniques to the detection of terrestrial invasive or endangered species may require sampling at intermittent water sources that are used for drinking and cooling; these water bodies may often be stagnant and turbid. We present our best practices technique for the detection of wild pig eDNA in water samples, a protocol that will have wide …

Low-Pathogenic Influenza A Viruses In North American Diving Ducks Contribute To The Emergence Of A Novel Highly Pathogenic Influenza A(H7n8) Virus, Yifei Xu, Andrew M. Ramey, Andrew S. Bowman, Thomas J. Deliberto, Mary L. Killian, Scott Krauss, Jacqueline M. Nolting, Mia Kim Torchetti, Andrew B. Reeves, Richard J. Webby, David E. Stallknecht, Xiu-Feng Wan

United States Department of Agriculture Wildlife Services: Staff Publications

Introductions of low-pathogenic avian influenza (LPAI) viruses of subtypes H5 and H7 into poultry from wild birds have the potential to mutate to highly pathogenic avian influenza (HPAI) viruses, but such viruses’ origins are often unclear. In January 2016, a novel H7N8 HPAI virus caused an outbreak in turkeys in Indiana, USA. To determine the virus’s origin, we sequenced the genomes of 441 wild-bird origin influenza A viruses (IAVs) from North America and subjected them to evolutionary analyses. The results showed that the H7N8 LPAI virus most likely circulated among diving ducks in the Mississippi flyway during autumn 2015 and …

Impact Locations And Damage To Civil And Military Rotary-Wing Aircraft From Wildlife Strikes, Brian E. Washburn, Paul Cisar, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Rotary-wing aircraft (e.g., helicopters and tilt-wing aircraft) are an important component of all U.S. military services and the U.S. civil aviation industry. Our analyses of wildlife strikes to military rotary-wing aircraft, both within the United States and during overseas deployments, as well as civil helicopters, have shown there are important patterns within wildlife strike data for flight operations conducted on airfields and during off -airfield missions. Birds accounted for 93% of the wildlife strikes where the animal was identified, and mammals (primarily bats) accounted for 7%. Wildlife impacted all parts of civil helicopters and military rotary-wing aircraft during strike events; …

Inventory Of Wildlife Use Of Mortality Pits As Feeding Sites: Implications Of Pathogen Exposure, Jeremy W. Ellis, Susan A. Shriner, Hailey E. Mclean, Lauren Petersen, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

To better understand the use of mortality pits by wildlife and possible pathogen dissemination from the resulting wildlife contact in these areas, we used 8 camera traps on 4 mortality pits in Colorado from June to December 2014 to create a species inventory and establish use estimates for those species. We observed 43 species visiting (in or near) the mortality pits during 1,168 total camera trap days. Of these, 24 species directly interacted with the mortality pits or carcasses contained within them. The most common visitors to mortality pits were raccoons (Procyon lotor), coyotes (Canis latrans), …

Reoccurrence Of Avian Influenza A(H5n2) Virus Clade 2.3.4.4 In Wild Birds, Alaska, Usa, 2016, Dong-Hun Lee, Mia K. Torchetti, Mary Lea Killian, Thomas J. Deliberto, David E. Swayne

United States Department of Agriculture Wildlife Services: Staff Publications

We report reoccurrence of highly pathogenic avian influenza A(H5N2) virus clade 2.3.4.4 in a wild mallard in Alaska, USA, in August 2016. Identification of this virus in a migratory species confirms low-frequency persistence in North America and the potential for re-dissemination of the virus during the 2016 fall migration.

Movement Of Hypophthalmichthys Dna In The Illinois River Watershed By The Double-Crested Cormorant (Phalacrocorax Auritus), Michael P. Guilfoyle, Heather L. Farrington, Richard F. Lance, Katie C. Hanson-Dorr, Brian S. Dorr, Richard A. Fischer

United States Department of Agriculture Wildlife Services: Staff Publications

Paired throat and cloacal swabs, along with feather samples, from nesting Double-crested Cormorants (Phalacrocorax auritus) at two sites in Illinois, USA, were tested for presence of invasive bigheaded carp (Hypophthalmichthys spp.) DNA. We also used DNA from the feather calamus to determine cormorant sex. Throat and cloacal swabs from cormorants at both locations tested positive for DNA from silver carp (H. molitrix), but none tested positive for bighead carp (H. nobilis). Hypophthalmichthys DNA was not detected on feathers. There were no significant differences among positive Hypophthalmichthys DNA detection frequencies between cormorant sexes. To …

Estimating Population Density For Disease Risk Assessment: The Importance Of Understanding The Area Of Influence Of Traps Using Wild Pigs As An Example, Amy J. Davis, Bruce Leland, Michael J. Bodenchuk, Kurt C. Vercauteren, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Population density is a key driver of disease dynamics in wildlife populations. Accurate disease risk assessment and determination of management impacts on wildlife populations requires an ability to estimate population density alongside management actions. A common management technique for controlling wildlife populations to monitor and mitigate disease transmission risk is trapping (e.g., box traps, corral traps, drop nets). Although abundance can be estimated from trapping actions using a variety of analytical approaches, inference is limited by the spatial extent to which a trap attracts animals on the landscape. If the “area of influence” were known, abundance estimates could be converted …

Wetland Bird Abundance And Safety Implications For Military Aircraft Operations, Kent Andersson, Craig A. Davis, Bradley F. Blackwell, Jason R. Heinen

United States Department of Agriculture Wildlife Services: Staff Publications

Wetlands with associated avifauna can pose a substantial hazard to aviation safety, potentially increasing bird–aircraft collision (strike) risk when located near air operations areas.We modeled year-round use by wetland avifauna of Drummond Flats Wildlife Management Area (Drummond Flats), a wetland complex located within 10 km of Vance Air Force Base (AFB), Enid, Oklahoma, USA. Our objectives were to 1) quantify seasonal avifauna abundances at Drummond Flats; 2) test a priori models reflecting use by bird species recognized as hazardous to aviation safety relative to environmental factors including flooded wetland habitat and vegetation cover; 3) use these models to predict maximal …

The Roles Of Habitat And Intraguild Predation By Coyotes On The Spatial Dynamics Of Kit Foxes, Robert C. C. Lonsinger, Eric M. Gese, Larissa L. Bailey, Lisette P. Waits

United States Department of Agriculture Wildlife Services: Staff Publications

Intraguild predation (IGP) by a dominant predator can drive the spatial dynamics of a subordinate predator and may explain space-use patterns that deviate from theoretical predictions that species will use areas that maximize the availability of limited resources (resource availability hypothesis). Intraguild predation may suppress the distribution and abundance of mesopredators, but spatial resource partitioning may facilitate coexistence, with the subordinate carnivore utilizing suboptimal habitats. In arid systems, free-standing water was historically scarce, limiting the distribution of larger-bodied predators and offering large areas of refugia for smaller, arid-adapted species, such as the kit fox (Vulpes macrotis). In these …

Adaptation Of The Aesop’S Fable Paradigm For Use With Raccoons (Procyon Lotor): Considerations For Future Application In Non‑Avian And Non‑Primate Species, Lauren Stanton, Emily Davis, Shylo Johnson, Amy T. Gilbert, Sarah Benson-Amram

United States Department of Agriculture Wildlife Services: Staff Publications

To gain a better understanding of the evolution of animal cognition, it is necessary to test and compare the cognitive abilities of a broad array of taxa. Meaningful interspecies comparisons are best achieved by employing universal paradigms that standardize testing among species. Many cognitive paradigms, however, have been tested in only a few taxa, mostly birds and primates. One such example, known as the Aesop’s Fable paradigm, is designed to assess causal understanding in animals using water displacement. To evaluate the universal effectiveness of the Aesop’s Fable paradigm, we applied this paradigm to a previously untested taxon, the raccoon ( …

Shifts In An Invasive Rodent Community Favoring Black Rats (Rattus Rattus) Following Restoration Of Native Forest, Aaron B. Shiels, Arthur Medeiros, Erica I. Von Allmen

United States Department of Agriculture Wildlife Services: Staff Publications

One potential, unintended ecological consequence accompanying forest restoration is a shift in invasive animal populations, potentially impacting conservation targets. Eighteen years after initial restoration (ungulate exclusion, invasive plant control, and out planting native species) at a 4 ha site on Maui, Hawai‘i, we compared invasive rodent communities in a restored native dry forest and adjacent non-native grassland. Quarterly for 1 year, we trapped rodents on three replicate transects (107 rodent traps) in each habitat type for three consecutive nights. While repeated trapping may have reduced the rat (Black rat, Rattus rattus) population in the forest, it did not appear …