Habitat Ecology and Management

Posters

 
Microhabitat Characteristics of River Otter Daytime Resting Sites
Tatiana Gettelman, Clayton Nielsen, Eric Schauber

River otters (Lontra canadensis) rely on daytime resting sites (DRS) for grooming, sleeping, and recovering from foraging, and will avoid areas without suitable DRS. Despite being a critical habitat component, microhabitat selection for DRS has not been analyzed for this species. During 2018-2020, we radiotracked 21 river otters in 12 socially-associated groups to 132 DRS. Of those sites, 51 were paired with 2-4 random locations each to develop Resource Selection Functions using conditional logistic regression. Kruskal-Wallis rank sum tests were used to compare differences in cover between site types and Pearson’s Chi-squared tests were used to compare the presence of beaver (Castor canadensis) and river otter sign at different DRS types. Of the 7 conditional logistic regression models run, the top model included percentage understory cover and the presence of beaver sign. All DRS were 0-30 m from water, with only 4 sites >5 m from water, and 59% were enclosed (i.e., bank dens, beaver lodges, or wood piles) while 41% were unenclosed (i.e., vegetation-only). Of the 65 vegetation-based DRS where plant species was recorded, 62% consisted of invasive Phragmites australis. Bank den and beaver lodge DRS both had lower understory cover and canopy cover than vegetation sites, but all sites had greater understory cover than random locations. River otter and beaver sign were present at 69% and 44% of DRS, respectively. Conversely, river otter and beaver sign were detected at 0.6% and 9% of random locations, respectively. Beaver are known to create and maintain suitable habitat for river otters, which was consistent with our findings. We conclude understory cover is an important habitat component of DRS when enclosed sites are not available, and is often not measured in landscape level analyses of habitat selection for river otters.

 
Evaluating Effects of Landscape Change on Mule Deer in Wyoming Sagebrush Ecosystems
Teagan Hayes, Tabitha Graves, Aaron Johnston, L. Embere Hall, Matthew Kauffman

Sagebrush ecosystems and wildlife that depend on them are under pressure from development, changing climate, as well as natural and human-caused disturbance.  Mule deer (Odocoileus hemionus) are of particular concern due to population declines across many western states. We initiated a study to evaluate landscape-level changes due to disturbances, habitat treatments, development, and climate change in Wyoming. We first performed a quantitative assessment of habitat and next plan to relate age ratios to habitat changes over a 39-year period (1980-2019). Natural and anthropogenic disturbances are distributed unequally in space and time across 37 herd units.  Oil and gas wells ranged from 4.1-0/km2, wildfire ranged from 25.09-0.00% of herd unit area, and habitat treatments ranged from 10.44-0.01% of herd unit area.  Age ratios generally showed a decline over time, though estimates fluctuate over time and by herd unit.  This project is part of a long-term study with the Wyoming Landscape Conservation Initiative.  Our findings will inform how changing conditions may influence long-term mule deer management, understand potential effects of future development and landscape change, and help to identify herd units with the greatest conservation and management needs.

 
Effects of Forest Management on Early-Successional Avian Species in the Southern Blue Ridge Ecoregion
Michael Adams, Amy Tegeler, Michael Hook, Michael Small, Beth Ross

Early-successional habitats are a critical habitat type for ruffed grouse (Bonasa umbellus) and golden-winged warblers (Vermivora chrysoptera). In the southern Blue Ridge Ecoregion, early-successional habitats have declined over the last 70 years, and the extent of which ruffed grouse and golden-winged warblers occupy these habitats at the edge of their ranges is unknown. The goal of this project was to assess the status and distribution of golden-winged warblers and ruffed grouse in the southern Blue Ridge Ecoregion. We also aimed to determine how management of early-successional habitats influences presence/absence of ruffed grouse and golden-winged warblers on public lands, and to evaluate the use of Autonomous Recording Units (ARUs) to detect and monitor both species. Using a conditional occupancy design, we surveyed for ruffed grouse (March 15th – April 30th 2020 and 2021), golden-winged warblers, and associated indicator species (May 5th – June 30th 2020 and 2021) at sites representing varying degrees of timber harvest management and controlled burning intensity. ARUs were placed at sites with and without positive detections of our target species. In 2020, ruffed grouse were detected at one site. In 2021, ruffed grouse were detected at seven sites. In 2020, prairie warbler occupancy was the greatest among indicator species (Ψ = 0.976). Our models failed to converge due to their nearly ubiquitous occupation of study sites. Field sparrow occupancy was estimated at Ψ = 0.656 and was positively influenced by shrub cover and visual obstruction yet negatively influenced by perimeter-to-area ratio of the occupied patch. Common yellowthroat warbler had the lowest occupancy estimate among indicator species (Ψ = 0.334) and this estimate was positively influenced by percentage of grassland at the 1-kilometer scale. This project will help inform habitat management and conservation of early-successional species and provide guidelines for future monitoring protocols.

 
Tallgrass Prairie Restoration on the Campus of Missouri Western State University, Saint Joseph, Missouri
Mark Mills, Jeff Powelson, Cary Chevalier, John Rushin

We have initiated a long-term prairie restoration project on the campus of Missouri Western State University (MWSU), St. Joseph, MO.  Previously, the site consisted of mostly hay fields and three wooded acres surrounding a small pond.  In 2019 we applied two herbicide applications coupled with mowing to remove nonnative plants and to prepare the site for planting in January 2020.  We used a seed mixture of approximately 150 species of prairie forbs and grasses donated by The Nature Conservancy’s Dunn Ranch near Eagleville, MO, with additional seed provided by the Missouri Department of Conservation (MDC).  The current plan calls for a 25-acre prairie unit that will consist of a mixture of warm-season grasses (e.g., Little Bluestem, Side-oats Grama, and Prairie Dropseed) and wildflowers.  Pollinator plots totaling 3.9 acres will receive plantings of pollinator-friendly plants with an emphasis on species preferred by monarch butterflies.  Five acres adjacent to the wooded area were planted in Sept. 2020 with a variety of hardwood trees (e.g., various oaks, hickory, black cherry, and walnut) spaced 40-60 feet apart to create a savannah.  We established three 6900 m2 experimental plots, each with a drift fence array with pit-fall traps, and have begun to plant a wheelchair-accessible interpretive prairie garden near the parking lot.  Additional plans include creating a GIS database, continuing to sample the flora and fauna, and conducting controlled burns next spring (2022).  This prairie site will serve students and faculty of MWSU as an area for laboratory exercises and undergraduate research projects.  Additionally, the MWSU cross country course runs through the prairie.  The prairie will also be open to public groups such as K-12 classes, scout troops, and other community groups.

 
Arthropod Biodiversity in Response to Juniper Removal Within Riparian Buffers
Josef Leachman, Heather A. Mathewson, Darrel Murray, Adam Mitchell, Kathryn Burton

Riparian ecosystems are declining globally due to increased anthropogenic and ecological pressures, including woody plant encroachment. This study focuses on surveying arthropod communities along riparian corridors as part of a long-term, upstream mitigation project on removal of Ashe juniper (Juniperus ashei). Arthropod communities play a critical role in the environment for their ability to promote or disrupt ecological processes through mechanisms like decomposition, herbivory, pollination, parasitism, or as food sources. Our objectives are to 1) survey arthropod community alpha diversity in response to juniper removal along riparian corridors and 2) monitor for seasonal or structural variation in the plant community. We will survey from May–July 2021 during peak arthropod production on a 282-ha site near Palo Pinto Mountains State Park in Palo Pinto and Stephens Counties, TX. We will utilize a suite of sampling techniques to minimize sampling bias of the community, which includes pit fall traps, vacuum sampling, light traps, bee pan traps, and aquatic dip nets. We will compare species richness and focal-species occurrence in areas that underwent juniper removal versus undisturbed areas that have high densities of juniper. Developing an understanding of arthropod community structure in response to juniper presence can aid in future research regarding habitat mitigation and restoration. 

 
Using Environmental DNA Collected from Snow Tracks to Confirm Species Presence on a Landscape.
Caleb Stanek, Jessie Golding

Federal and state managing agencies have multiple mandates that require monitoring of rare species. The Northern Region of the Forest Service’s Multispecies Mesocarnivore Monitoring Program is using a framework for monitoring rare species that accommodates a flexible question structure: goal efficient monitoring (GEM). The first question in the GEM framework looks at species presence and asks the question, Is the species present, as knowledge of rare species is often sparse. However, efficiently answering this question over a single season can be challenging, particularly when a species is very rare. Fortunately, in the US Northern Rockies snow track surveys are an effective way to detect even single individuals because of the abundance of the sign (i.e., multiple kilometers of tracks per day) relative to the animal (a single organism). In addition, a recent novel technique of genetic sampling using environmental DNA (eDNA)–DNA shed from an organism in its environment coupled with quantitative PCR (qPCR) in snow tracks allows for reliable identification of tracks. We tested the efficacy of using snow track surveys with combined eDNA sampling from January through March of 2020 in Montana across three National Forests (Custer-Gallatin, Helena-Lewis and Clark, and Lolo) for five mesocarnivore species: fisher (Pekania pennanti), Pacific marten (Martes caurina), American martens (Martes americana), lynx (Lynx canadensis), and wolverine (Gulo gulo). Using this combined method we were able to efficiently answer the GEM species presence question with a DNA confirmed detection; for example, in northwest Montana for lynx, it took three days to genetically confirm presence through eDNA from snow tracks. Preliminary results indicate that eDNA from snow tracks yielded adequate amounts of DNA at a high success rate (79% of all collected samples) and could be a very effective method to answer GEM questions for multiple rare, elusive species at a large scale.

 
Using Small Mammal Population Analysis to Examine Efficacy of Prairie Restoration
Faith James, Olivia Vergin, Joe Whittaker, Peyton Lehman, Zachary Buchholz, Kelly Lorenz

As urban expansion converted wildlife habitats into agricultural and industrial land, native prairie lands were reduced to 1% of their original area. This increased habitat fragmentation and disrupted species dynamics and populations. Small mammals are vital to prairie ecosystems because they consume plant material and invertebrates, disperse seeds, and provide a source of food for larger species. Trapping of remnant and restored prairies provides data on small mammal density and diversity. Comparing population data between remnant and restored prairies can inform successful management and restoration practices. We trapped small mammals in various remnant and restored prairies in northwestern Minnesota from 2012 to 2020 with the goal to compare small mammal species diversity as well as to monitor populations of rare species. We hypothesized that there would be a difference in species diversity between restored and remnant prairies. We set two to three grids with 50 traps (alternating Small Sherman, Large Sherman, and Longworth) per grid. When a mammal was captured, we identified species, sex, and mass, and then marked for recapture. We collected body measurements and saliva samples from Peromyscus species for species identification. Our data analysis includes Simpson’s Reciprocal Diversity Index, population trends, and species comparisons between restored and remnant prairies. Through our prairie surveys, we document occurrences of rare species, such as Perognathus flavescens. Our findings will help inform future management decisions. 

 
Herptile Microhabitat Usage Within the Palo Pinto Mountains – SRIP
Marshall Mills, Heather A. Mathewson, Kathryn Burton
Mills, M., H.A. Mathewson, and K. Burton. 2021. Herptile Microhabitat Usage Within the Palo Pinto Mountains. Poster Presentation. The Wildlife Society Virtual Conference. November 1-5. Abstract Due to its large size, Texas has a multitude of ecoregions that provide habitat for many species of reptiles and amphibians. For conservation of species and biodiversity, it is important for us to understand habitat use by reptiles and amphibians. In our study region, there have been very few studies focusing on the utilization of different microhabitats by reptiles and amphibians. The objective of this research was to determine microhabitat patterns of use by terrestrial herptile species. Our study area is located in the Cross Timbers ecoregion, near Strawn, Texas, USA in Palo Pinto and Stephens Counties on 2 properties owned by Texas Parks & Wildlife Department. Both properties contain ponds, ephemeral and intermittent streams, and rocky or brushy upland areas. We randomly selected 15 sites along terrestrial uplands and we began monthly afternoon surveys in June 2021. Surveys consisted of flipping rocks and logs, and examining brush piles and leafy litter. We recorded detections of all reptiles and amphibians using a GPS. We recorded the following microhabitat variables: substrate type, ambient temperature, relative humidity, soil temperature, rock and log dimensions, slope of the general area, wind speed, soil moisture, and distance from water sources if within 50 m. We will use the microhabitat variables to determine what best predicts habitat use for our most commonly detected species. This information will contribute to our knowledge of habitat requirements for herptiles in the Cross Timbers region of Texas and will assist Texas Parks & Wildlife with management and conservation of these species.
 
The Ecological Risk and Transport of Poly- and Perfluoroalkyl Substances in a Tidal Freshwater Potomac River Ecosystem – SRIP
Tabitha King, Thomas Huff, Gregory Foster, Amy Fowler
Per- and polyfluoroalkyl substances (PFAS) are a class of over 4,000 synthetic compounds with a variety of applications such as flame retardants, aqueous film-forming foams (AFFF), oil- and water-resistant coatings, and industrial manufacturing processes. Their molecularly-stable nature substantially reduces their ability to biodegrade – fueling concerns of environmental persistence and bioaccumulation in wildlife, aquatic organisms, and humans. Recent environmental toxicology research has revealed links between PFAS exposure and health risks including cancer, liver damage, thyroid disease, and reduced fertility in humans and wildlife. In February 2019, the US EPA established a PFAS Action Plan to gather information to address PFAS that have been, and are still, being released into the environment. In the United States, there is a deficiency of PFAS presence data in locations without a known history of incidental and accidental releases. In order to better understand the extent of the ecological risk in a local water body, this study investigates the presence, concentration, and trophic transfer of PFAS in a section of the Potomac River (approximately 18 km south of Washington, D.C.). Isotopic analyses have identified established food web connections at two embayments downstream from wastewater treatment plants. From May to September 2019, surface water, sediment, macrophyte, plankton, and banded killifish (Fundulus diaphanus) were collected once a month and extracted using modified solid phase and QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction techniques. Over 25 PFAS were targeted using triple quadrupole liquid chromatograph mass spectrometer (LC-MS/MS) instrumentation. The bioaccumulation potential of detected PFAS will be evaluated using bioaccumulation, bioconcentration, biomagnification, and trophic magnification factors.
 
Winter Microhabitat Selection and Greater Sage-Grouse Response to Weather Severity – SRIP
Caitlyn Powell, Jeffrey Beck, Kurt Smith, Aaron Pratt
Winter habitat used by greater sage-grouse (Centrocercus urophasianus ‘hereafter, sage-grouse’) is characterized by moderate topography within a mosaic of sagebrush (Artemisia spp.) of differing height and cover. This mosaic ensures access to forage and shelter among variable snow depths. How sage-grouse select winter habitat in response to severe weather is less understood. Our objective was to evaluate predictors of sage-grouse microhabitat selection in response to severe weather in Wyoming’s Red Desert. We monitored 52 adult female sage-grouse equipped with GPS transmitters during winters 2018/2019 and 2019/2020. When weather was severe, we expected less movement resulting in smaller daily home ranges. We calculated a winter severity index (WSI) within daily home range polygons that incorporated multiple weather metrics (snow depth, temperature, wind velocity, precipitation) using SnowMet at 30-m resolution.  We employed a resource selection function modeling to evaluate whether sage-grouse selected areas with lower WSI values. To quantify microhabitat structure, we identified 90 grouse locations, 90 randomly-generated locations within home ranges, and 90 locations at the population range scale, encompassing winter 2019/2020. During summer 2020, we sampled winter microhabitat structural characteristics along 50 x 50 m transects at these 270 locations to record canopy cover, density, and height for each shrub species as well as visual obstruction. To model sage-grouse winter microhabitat selection, we paired each use location with a home range and population range random location (dependent variables) and regressed these against shrub community structure along each transect and the WSI value from the day of bird use. When weather was severe, we expected sage-grouse to mediate weather severity by selecting greater shrub concealment at the microhabitat scale. Information on microhabitat that sage-grouse select to maximize their survival during severe winter conditions will better inform conservation of critical wintering habitats to promote population persistence under changing climatic conditions.
 
Assessing Long-Term Changes in Lesser Prairie-Chicken Habitat Quality Across the Sand Sagebrush Prairie Ecoregion – SRIP
Megan Vhay, David Haukos, Daniel Sullins
Lesser prairie-chicken (Tympanuchus pallidicinctus) populations have declined by an estimated 90% in recent decades, with the lowest contemporary population estimates occurring in the Sand Sagebrush Prairie Ecoregion of the southwestern Great Plains. Drivers contributing to these declines are unclear, but include conversion of native prairie to row-crop agriculture, increased anthropogenic disturbance, and overall reduction of habitat quality throughout the lesser prairie-chicken’s range. We hypothesize that recent changes in habitat quality, rather than quantity, are the main drivers of lesser prairie-chicken declines. Our objective is creation of a comprehensive overview of landscape-scale changes in the Sand Sagebrush Prairie Ecoregion since the contemporary high lesser prairie-chicken population of the mid-1980s. We reconstructed landcover change and delineated patch types in the ecoregion using satellite imagery and aerial photography in three- to five-year intervals. Using FRAGSTATS, we measured landscape- and patch-scale metrics including number of patches, edge, and contagion. We summarized the number of anthropogenic structures and trees throughout the ecoregion for the same time period. We anticipate finding a loss of native prairie, increased fragmentation of remaining prairie, decreased optimal densities of sand sagebrush, increased density of both anthropogenic features and trees throughout the ecoregion, and increased fragmentation of remaining native prairie. Our study will provide insight into aspects of marked change in habitat quality for lesser prairie-chickens in the Sand Sagebrush Prairie Ecoregion, providing a basis for investigation into finer-scale changes.
 
Assessing the Impacts of Hiking Trails on Predation of Artificial Ground Nests in a Conservation Area – SRIP
Jenna Myers, Michael Bender, Jessica Patterson, Jacob McDonald
In recent decades, bird populations have experienced precipitous declines worldwide. According to current estimates, approximately 3 billion birds have been lost in North America, with approximately 60% of species that breed in eastern forests experiencing declines. A thorough understanding of the myriad of local factors influencing populations is necessary for managers to mitigate population threats. Habitat change is the primary driver of worldwide avian declines, but nest predation is a leading cause of reproductive failures. To better understand factors influencing nest predation, our primary objective was to assess impacts of hiking trails in Chicopee Woods Nature Preserve, a conservation area identified by the National Audubon Society as an important bird area in Georgia. Because trails may act as either preferred travel routes or avoided areas due to human activities, we hypothesized that hiking trails influence predator behaviors, which in turn impacts nest predation. To evaluate this hypothesis, we documented predation of 50 pairs of artificial ground nests, each containing two chicken eggs and located within 1-5m of trails or approximately 50m from trails. To accomplish our secondary objective of documenting the community of nest predators in the preserve and determining habitat associations for predators, game cameras were paired with additional nests placed throughout the preserve. Preliminary results, analyzed in R and visualized with ArcGIS Pro, suggest that proximity to trails does not influence the likelihood of nest predation, indicating that broader factors may influence predation rates. While documenting the community of nest predators is still in progress, nest depredation evidence and camera trapping images indicate the presence of avian and mammalian nest predators in the preserve. Our data indicate predation rates within our study site are similar to those documented in other forested landscapes, and predation is likely affected more by roads that fragment forested landscapes than by hiking trails.
 
Hungry Hungry Herbivores: 20-Year Impacts of White-Tailed Deer Exclusion – SRIP
Gabrielle Ripa, Steve Demarais, Joshua Granger, Richard Hamrick, Raymond Iglay
White-tailed deer (Odocoileus virginianus; hereafter: deer) are the most abundant herbivore in the eastern United States and actively impact understory vegetation communities.  Despite multiple short-term studies (average 8.0 ± 0.4 years), long-term impacts to vegetation structure and composition as well as deer nutritional carrying capacity (NCC) are merely presumed. Therefore, our objectives were to determine changes in vegetation composition and structure, as well as potential effects on NCC among 0, 5, and ~20 years of deer exclusion. Three paired control and exclosure plots (~2.7 ha each) were created on three Wildlife Management Areas (WMAs) representing the Upper Coastal Plain, Lower Coastal Plain, and Mississippi Alluvial Valley ecoregions of Mississippi in 2000. Vegetation species composition and structure will be measured during May and June 2021 at 10 systematic sampling points within each of the control and exclosure plots and complemented by 15 1-m2 biomass plots clipped during July 2021. Biomass samples will be dried and weighed and the combination of forage quantity and quality analyzed at 14% crude protein content to measure changes in NCC. Camera surveys conducted during February and March of 2021 will provide an estimate of deer abundance on each WMA, complementing deer exclusion with potential deer impacts. We predict midstory basal area and canopy coverage will be greater inside exclosures than in control plots resulting in less understory plant coverage, especially coverage of shade intolerant species. Consequently, we expect nutritional carrying capacity to be greater in control plots compared to exclosures due to the lack of high-protein herbaceous plants in exclosures. 
 
Summer Roost-Site Selection of a White-Nose Syndrome Impacted Bat Species – SRIP
Sarah Zirkle, Sarah Krueger, Trevor Walker, Catherine Haase
The tri-colored bat (Perimyotis subflavus) is a hibernating North American bat species that utilizes forested landscapes during summer months; however, information on the spatial ecology and summer habitat requirements of the tri-colored bat is limited. Summer habitats are critically important to population persistence as they support multiple life history requirements, including maternity colonies, nursery sites, and foraging locations. As tri-colored bats are highly susceptible to white-nose syndrome, a devastating disease that increases fat consumption over hibernation, determining the resources that are important for building up pre-hibernation fat stores is crucial. Our objective is to quantify the selected resources of tri-colored bats for roost sites during the summer. We will capture, tag, and track bats using radio-telemetry to their roost locations. At each roost, we will record roost habitat characteristics, including roost tree height, canopy density, surrounding forest species composition, and other forest descriptions. We will repeat these measurements for three random trees to serve as the habitat available for selection. We will use a suite of mixed conditional logistic regression models with individual as a random effect to evaluate the relationships between covariates and habitat selection at the roost tree and individual level. Preliminary results from five bats demonstrate roost tree selection was influenced by roost tree height, which may be linked to microclimatic factors. Future field work will increase sample size and provide a more robust analysis. There is a critical information gap for the ongoing recovery of tri-colored bats; better understanding of summer habitat and proper forest management implications, as well as information on scale-specific habitat selection, is needed to better understand tri-colored bat management needs.
 
Environmental Impacts on Invasive Aquatic Plants in the Lower Hudson Region – SRIP
Teresa Pacelli
Invasive aquatic plant species are a major threat to freshwater ecosystems. Understanding the environmental factors that influence plant invasions is important for developing management strategies. We identify potential environmental and seasonal influences on invasive species communities within 46 water bodies in the Lower Hudson River Watershed in southern NYS, USA. Water bodies were surveyed for invasive aquatic plants in 2019 and 2020 by volunteers of the aquatic invasive species program of the Lower Hudson Partnership for Regional Invasive Species Management. Surveyors documented abundance of a set of target invasive species at each water body. We examined differences in species richness within water bodies surveyed in both the early and late growing seasons. We associated environmental conditions such as water body depth and area, allowed boating and recreational use types, measures of public access, etc., with multivariate measures of community similarity calculated based on relative density measures using non-metric multidimensional scaling. We found that while invasive species composition changed between early and late growing seasons within many water bodies in 2019, there were no significant differences in invasive species richness between seasons. Multivariate analyses of survey data across growing seasons, but separated by year, showed substantial differences in community composition among water bodies and suggested that key factors driving these differences are water body area (acres) and access type (public, public with permit, private, no access). Further analysis is needed, preliminary results suggest some influences that are within managers’ control.
 
Benthic Macroinvertebrate Community Responses to Wastewater Treatment Plant Discharges in Central Wisconsin – SRIP
Isabel Dunn
Municipal wastewater treatment plants provide necessary services for municipalities and receiving waters through removing contaminants from wastewater and converting it into an effluent that can be returned to the environment. Effluents from wastewater treatment plants can negatively affect the water quality of receiving waterbodies, an important aspect of aquatic habitat. It is necessary to assess the impacts from these discharged effluents to better manage water quality for both humans and aquatic ecosystems. Changes in water quality are often expressed by the benthic aquatic macroinvertebrate community. Because these organisms respond to anthropogenic impacts in predictable ways, examination of macroinvertebrate community metrics can provide valuable insights on the ecological condition of these waterways. Aquatic macroinvertebrates were kick net sampled both upstream and downstream from the discharge point of four mid-sized wastewater treatment facilities in central Wisconsin. Basic water chemistry and physical stream characteristics were recorded at each sample location. Family-level taxonomies were used to compute metrics based on community composition, richness, tolerance, and trophic function. Paired t-tests were ran on four metrics that displayed the least variation (taxa richness, Family Biotic Index, % dominant three taxa, and % collector-gatherer taxa) to determine if significant differences existed between macroinvertebrate metrics upstream and downstream of the discharge from wastewater treatment plants. Metrics generally responded as expected and reflected a decrease in water quality downstream of the plants, although only richness exhibited a statistically significant change upstream and downstream. The factors causing the significant difference in richness, but not the other metrics, were not identifiable. Stream chemical and physical measurements were also examined to explain metric responses. Overall, the wastewater treatment plants sampled appear to be managing their effluents well.
 
Grazing Pressure of Bison on Arthropods and Vegetation Communities at Caprock Canyons State Park, Texas – SRIP
Ty Cosper, Molly Koeck, Heather A. Mathewson, Adam Mitchell, Donald Beard
In 1997, Texas Parks and Wildlife Department (TPWD) relocated 36 southern plains bison (Bison bison bison) to Caprock Canyon State Park, a 6,070 ha state park in Briscoe County, Texas, USA. There are now over 250 bison in the park and to manage the herd and the park, TPWD is interested in knowing about grazing pressure on the land. The objective of this study is to determine what affect the bison have on the vegetation and arthropod community in the park. In summer 2018, TPWD established 18 3 x 3 m2 fenced in areas to create grazing-exclusion plots. From Spring 2020–Spring 2022, we are surveying the plant and arthropod community in grazed areas and grazing enclosures once a month. We randomly place 2 Daubenmire frames in the enclosed area, and 2 frames 20 m away in a random direction from the enclosed area, in available for grazing. Inside each of the 4 Daubenmire frames we estimate bare ground, litter, plant diversity, and height. We collect arthropods using one pitfall trap (9oz cup) and a bee bowl (18oz cup), colored fluorescent yellow, white, and blue to attract pollinators’ we randomly select the color of the bee bowl for each point in every survey. With this information Caprock Canyon State Park, can create a plan on how to manage the size of the bison herd and the vegetation and arthropod communities in the areas grazed by the bison.

Posters
Location: Virtual Date: November 2, 2021 Time: 11:00 am - 12:00 pm