2025 Midwest Fish & Wildlife Conference

AUTHORS: Ashley G. McDonald, Southern Illinois University; Jennifer R. Schultze, Southern Illinois University; Clayton K. Nielsen, Southern Illinois University; F. Agustin Jimenez, Southern Illinois University

ABSTRACT: Zoonoses are attributed to approximately 75% of emerging infectious diseases. Contraction of zoonotic infections is linked to urbanization, as land development increases the probability of human interaction with wildlife. Omnivorous animals such as raccoons thrive in urban settings due to the abundance of anthropogenic resources such as food and shelter. Racoons are the definitive host of zoonotic pathogens, including the heteroxenous raccoon roundworm (Baylisascaris procyonis); raccoon synanthropic habits bring these pathogens near human dwellings. The goal of this study is to assess the influence of raccoon abundance on the prevalence of raccoon roundworm in 5 study areas in northern Illinois representing a rural-urban gradient. Raccoons (n=287) were captured and removed from sites by collaborators during April-June 2022-2024. Upon necropsy, intestinal tracts were examined to determine raccoon roundworm prevalence. Capture per unit effort (CPUE), a measure of wildlife population abundance, was calculated as the number of raccoons captured per 100 nights of capture effort at each site. A logistic regression was used to investigate the relationship between raccoon abundance and raccoon roundworm prevalence. Raccoon roundworm prevalence decreased with increased raccoon abundance (X2=4.37, P=0.036). Counterintuitively, our findings suggest that disease risk decreases with increasing raccoon abundance, which implies that population reduction of raccoons in areas of high abundance might be an ineffective tool to reduce the risk of roundworm infection to the human population. Land-use can also impact parasite prevalence, as the availability of anthropogenic resources can influence raccoon population dynamics. Future analyses examining the relationship between land-use, raccoon roundworm prevalence, and raccoon abundance might provide a better understanding of the influence of population demographics on raccoon roundworm prevalence.

AUTHORS: Brittany R. Schweiger, HDR Engineering, Inc

ABSTRACT: Four of the seven federally listed bat species in the U.S. occur in the north-central region, and two of the remaining seven are being evaluated for listing under the Endangered Species Act. Regulations at the state and federal level often require consultation to assess the impacts to these species before development occurs. In the energy sector, development is rapidly occurring—from power line upgrades to utility-scale solar. In the U.S., there are over 15,000 miles of power lines throughout the country and, in 2023, solar accounted for 55 percent of new electricity-generation capacity. The electric grid infrastructure is aging and, as the population grows and the demand for reliable, clean energy increases, upgrades to transmission systems and additions of utility-scale solar generation are needed. While energy is essential to society, it can have impacts to protected bat species, including the removal of habitat. Therefore, energy projects must understand how bats can influence projects and how to evaluate impacts to bats as a result of construction activities accurately and appropriately during the planning phase. This presentation will highlight species threats, current regulations, the latest species survey guidelines, issues encountered, conservation measures, approaches toward impact minimization, and lessons learned with respect to solar and energy development in many areas of the north-central region. This presentation will be valuable for developers, consultants, regulators, and those interested in the intersection of energy projects and protected species.

AUTHORS: Thomas J. Benson, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Tara A. Beveroth, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Claire A. Johnson, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Edward P. Price, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Timothy A. Rye, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Emily J. Lain, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; Brian M. Charles, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign; and David N. Zaya, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign

ABSTRACT: Starting in the second half of the 20th century, agricultural intensification increasingly involved the use of chemicals for pest control. The development of numerous synthetic pesticides, including herbicides, insecticides, and fungicides, led to widespread use and, in some cases, recognition of widespread non-target effects on organisms. Unfortunately, our understanding of the potential effects of these pesticides on non-target organisms generally lags behind their widespread adoption, as does our understanding of the extent to which these chemicals travel beyond the agricultural fields in which they’re applied and end up in natural areas. In 2023, we set out to examine the extent of plant damage consistent with non-target herbicide exposure as well as to quantify concentrations of pesticides from plant tissue and soil from natural areas throughout Illinois. We sampled >180 sites in Illinois 2 times during the growing season of 2023 and found at least moderate damage to plants at almost all sites, with >50% of sites having severe damage and oak species most frequently affected. We found pesticides in nearly all natural areas, with 40 different chemicals detected, primarily from plant tissues. Herbicides were found in the greatest concentrations, with Atrazine and 2,4-D most common, and Dicamba relatively rare. Later in the season, fungicides and insecticides were more commonly detected. The amount of row-crop agriculture in the surrounding kilometer predicted leaf-tissue concentrations of pesticides and severity of plant injury. The longer-term effects of this exposure and plant injury are unknown, as are the effects on insects and insectivorous birds. Given that oaks were the most frequently observed with plant damage, and the disproportionate importance of this group for caterpillars and the migrating and breeding birds that consume them, more work is needed to explore these implications.

AUTHORS:  Shauna S. Sayers, School of Forestry and Horticulture, Southern Illinois University; Brent S. Pease, School of Forestry and Horticulture, Southern Illinois University; Michael V. Cove, North Carolina Museum of Natural Sciences.

ABSTRACT:  Non-native invasive species are a leading contributor to global biodiversity loss. The Burmese python (Python bivittatus), a large constrictor snake native to Southeast Asia, is one of Florida's most notable exotic predators. Although python’s prey vary in size and species, rodents are the most common group detected in their digestive tracts. The Key Largo woodrat (Neotoma floridana smalli) and Key Largo cotton mouse (Peromyscus gossypinus allapaticola) are two endangered rodent subspecies, endemic to Key Largo, Florida, that are susceptible to the threat of increasing python prevalence. We examined the impact of Burmese pythons on these two subspecies by conducting spatial capture-recapture surveys at 23 grids and deploying remote cameras at 629 supplemental woodrat nests across North Key Largo from January to August 2024. Trapping effort concluded with a total of 4,309 trapnights, capturing 37 woodrats (17 individuals) and 268 cotton mice (152 individuals). The effects of python presence on woodrat and cotton mouse populations were examined by comparing current rodent abundance estimates to those estimated during the python’s apparent establishment and increasing prevalence. Our results indicate the abundance of woodrats and cotton mice has declined coinciding with the increasing detections of pythons, with more drastic declines in the larger woodrats. Preliminary SECR estimates show a decrease in woodrat density from 0.48 individuals per hectare in 2017 to 0.08 individuals per hectare in 2024. Furthermore, our analysis demonstrated that areas with higher python activity exhibited altered habitat use patterns by woodrats such as decreased nest use and stick-nest building. These results suggest that as pythons increase their population size and distribution, the already geographically limited woodrats and cotton mice may continue to experience population declines and shifting habitat use.

AUTHORS: Olivia P. Reves, Department of Natural Resources and Environmental Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA; Mark A. Davis, Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, IL, USA; Eric R. Larson, Department of Natural Resources and Environmental Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA



ABSTRACT: The conversion of natural ecosystems to agriculture is a leading cause of habitat loss and threatens global biodiversity. For the past two centuries, the midwestern United States has experienced agricultural intensification and expansion, resulting in losses of natural ecosystems including tallgrass prairies, wetlands, and forests. Forest cover in states like Illinois has increased over the last several decades, partially due to agricultural conservation efforts like agroforestry, the Conservation Reserve Enhancement Program, and implementation of riparian buffers. However, does this increasing forest cover, intended to reduce nutrient and soil loss and benefit in-stream biota, also have benefits to terrestrial biodiversity? We used environmental DNA (eDNA), DNA collected and isolated from environmental samples, to evaluate how forest cover influences and potentially benefits terrestrial and semi-aquatic vertebrates in agricultural landscapes. In May and June of 2024, we collected eDNA samples from 47 low order streams over gradients of both riparian and whole-watershed forest cover from the U.S. National Land Cover Database. We then conducted eDNA metabarcoding of vertebrate communities using 12S and COI primers. Next, we used generalized linear mixed models to examine effects of forest cover on species richness, as well as non-metric multidimensional scaling to explore differences in community composition between sites of varying forest cover. Evaluating how terrestrial vertebrate communities respond to forest cover can shape management practices from riparian buffers to watershed-wide scales across agricultural regions.

AUTHORS:  Bianca Saftoiu, University of Illinois Urbana-Champaign; Dr. Mark Johnson, US Army Construction Engineering Research Laboratory; Patrick Wolff, US Army Construction Engineering Research Laboratory; Dr. Jinelle Sperry, University of Illinois Urbana-Champaign and US Army Construction Engineering Research Laboratory

ABSTRACT:  Tall-grass prairies are among the most threatened ecosystems in North America with less than 0.01% remaining in the state of Illinois. Effective prairie restoration in the Midwest is thus essential and requires that the health of the ecosystem be managed by re-establishing functional ecological communities, including prairie-associated wildlife species. Small mammals serve as an effective taxonomic group to monitor given their importance to ecological functioning across trophic levels and their sensitivity to habitat disturbance. Various passive and invasive survey methods have been used to evaluate mammalian species because of challenges associated with varying body size, temporal activity patterns, and cryptic behaviors. In this study we compare three distinct methods including live trapping, bucket camera traps, and airborne environmental DNA (eDNA) sampling for monitoring small mammal communities in restored prairies. In 2023 we surveyed ten prairie sites in Illinois and found that live trapping allowed for more specific identification to the species level while bucket cameras generally detected a greater species richness. We were also able to detect vertebrate DNA within the ten prairies using eDNA methods, however, the quantity of DNA varied across sites. Based upon these preliminary results, we can infer that a combination of both traditional and modern methods will offer a more comprehensive assessment of small mammal community composition within restored prairies.

AUTHORS:  David Delaney, Iowa State University
Tyler Harms, Iowa Department of Natural Resources
Stephen Dinsmore, Iowa State University


ABSTRACT:  Techniques to estimate density of unmarked animals are logistically feasible and allow sampling over greater spatial extents than more intensive methods, such as mark-recapture. However, accuracy of density estimates relies on the validity of assumptions about the study system. We conducted a thermal-imaging drone survey at night to test the validity of two assumptions for conducting distance sampling on white-tailed deer (Odocoileus virginianus) in Iowa via nocturnal spotlight surveys. First, we tested whether deer are randomly distributed with respect to gravel roads, which represent line transects in our study. Second, we quantified the portion of the population that occurs in unsampleable locations (i.e., within forest) to estimate availability bias. Preliminary analyses suggest deer do not avoid gravel roads but do responsively move away from observers prior to being detected, leading to potential bias in estimates of detection probability and density. Secondly, deer increased the use of forest cover as spring vegetation green-up occurred, leading to up to 50% of the population being unavailable to sample during surveys. Each of these deviations from conventional distance sampling assumptions inform future sampling design protocols and can be analytically corrected, once quantified, to reduce bias in density estimates.