Midwest Fish & Wildlife Conference 2018

AUTHORS. Kalysta Adkins, University of Minnesota; Charlotte Roy*, Minnesota Department of Natural Resources; David Andersen, University of Minnesota; Robert Wright, Minnesota Department of Natural Resources

ABSTRACT. The Conservation Reserve Program (CRP) has the potential to influence the abundance of greater prairie-chickens (Tympanuchus cupido pinnatus), a species of special concern in Minnesota, by altering the amount and configuration of grassland and wetland in agriculturally dominated landscapes. However, the CRP has experienced recent declines in enrollments in northwestern Minnesota, and these declines are expected to continue following the reduced enrollment cap in the 2014 Farm Bill, which funds the program through 2018. These cuts increase the need to prioritize CRP reenrollments or new enrollments that are likely to have the most impact on greater prairie-chicken populations. To predict changes in greater prairie-chicken abundance caused by expirations of CRP contracts and target CRP enrollments at both the landscape and lek scale, we used models relating lek density and the number of males at leks to CRP enrollments and the resulting landscape structure. We simulated different land cover scenarios of CRP contract expirations, and results indicated that the abundance of greater prairie-chickens would be negatively impacted following scheduled expirations. Simulations of targeted CRP contract enrollment in both small, random enrollment scenarios and large, non-random enrollment scenarios suggested mixed effects on greater prairie-chicken abundance. Adding grassland cover that increased existing grassland contiguity had a positive impact, while additions that decreased contiguity had a negative impact. Landscapes with a large proportion of existing CRP grasslands and wetlands were most likely to continue to support high prairie-chicken abundance through reenrollment and enrollment of new contracts that are large (> 20 acres) and contiguous with existing grassland and wetland cover types. 

AUTHORS. A.J. Gregory*, Bowling Green State University; C. Roy, Minnesota Department of Natural Resources; E. Nelson, Minnesota Department of Natural Resources

ABSTRACT. Minnesota DNR recognizes two distinct management units of Sharp-tailed grouse (Tympanuchus phasianellus). Recent population declines in the East-Central Management Unit (EC) has led to speculation that the EC sharp-tailed grouse population may be experiencing diminishing returns in reproductive success due to inbreeding depression. Alternatively, others have suggested that declines are due to habitat loss or degradation. To evaluate relative support for these hypothesized mechanisms for EC population declines, we conducted a landscape genetic analysis to assess contemporary levels of genetic diversity and gene flow, and to test for a genetic bottleneck. Cooperating biologists collected feathers from lek sites and hunters submitted wing samples, which were analyzed at 15 microsatellite loci. Genetic diversity was high (HO=0.771), the inbreeding coefficient was low (FIS=0.017), and a significant excess in heterozygosity (P=0.005) was detected. Population clustering analysis indicated greatest support for three populations; however, mapping sample locations of individuals by assigned population cluster revealed panmixia of population clusters. In sum, our findings are consistent with a recent demographic compression or bottleneck, but the EC population still retains high genetic diversity. Therefore, inbreeding depression was not supported, and declines are more consistent with changes in habitat quantity or quality.     

AUTHORS. Nicole M. Davros, Lindsey N. Messinger - Farmland Wildlife Populations & Research Group, Minnesota Department of Natural Resources

ABSTRACT. Ring-necked pheasant (Phasianus colchicus) responses to the amount of grassland acres on the landscape have been well documented but we lack current information on the individual components of reproductive success that help drive pheasant population dynamics in Minnesota. As acres enrolled in private lands conservation programs (e.g., Conservation Reserve Program) continue to decline, it has become more critical to understand the demographics of these populations, especially in the context of habitat management on public lands. Our objective was to evaluate pheasant productivity in relation to within-patch diversity (e.g., sites dominated by smooth brome (Bromus inermis), warm-season grasses, and high-diversity grass/forb mixtures) in grassland reconstructions. From early spring 2015 through spring 2017, we radiocollared 122 hens on 2 project areas in southwestern Minnesota and collected data on nest site selection and nest survival each year. Preliminary analyses using 2015 data showed that all hens selected nest sites with slightly less grass cover, lower species richness, and shallower litter depth compared to random survey points. Hens that successfully hatched nests selected sites with less grass and forb cover but more standing dead vegetation cover, reduced species richness, and reduced vegetation density. Overall, the daily survival rate (DSR) was 0.9406 ± 0.41 (range: 0.8731-0.9729). Future analyses will examine the role of vegetation, spatial (e.g., distance to edge), and temporal (e.g., nest age, ordinal date, year) covariates on nest site selection and nest survival. Our findings will be discussed in the context of habitat management with the goal of helping natural resource managers prioritize grassland management and land acquisition strategies.

AUTHORS. Alixandra Godar, Adela Annis - Kansas State University/Kansas Cooperative Fish and Wildlife Research Unit; David Haukos, U.S. Geological Survey, Kansas Cooperative Fish and Wildlife Research Unit; Jeff Prendergast, Kansas Department of Wildlife, Parks and Tourism

ABSTRACT. Agricultural producers are besieged with information about potential benefits of spring cover crops for their fields, but struggle to find information about benefits for wildlife. In western Kansas, many landowners not only manage their property for agricultural production but also for ring-necked pheasant (Phasianus colchicus) habitat. Declining pheasant populations have raised questions about potential, affordable management strategies for landowners to aide local pheasant populations. Managers have theorized that spring cover crops, used when transitioning between a summer row crop, primarily corn (Zea mays) or sorghum (Sorghum bicolor), to winter wheat (Triticum aestivum), may provide nesting and brood rearing cover for pheasants and other birds. We divided three fields into 4 treatments, including a chemical fallow control plot and three cover crop mixes. Hens were captured in close proximity to cover crop treatment fields and outfitted with 15-g very-high-frequency necklace-style radio transmitters. During the 2017 breeding season, we monitored 21 radio-collared female pheasants and collected >1,500 locations. Triangulated locations were used to estimate home ranges using minimum convex polygon (MCP) and kernel density estimators (KDE). We assessed habitat use with both Resource Selection Functions and Resource Utilization Functions (RUF) focusing on the relative use of different cover crop mixes and other available cover types. Hens selected for Conservation Reserve Program/Grasslands at 2nd and 3rd order selection levels over all other cover types. The RUF found hens selected against growing crop and crop stubble. Hens selected for the cover crop mixes in the RUF. Among the cover crop mixes, GreenSpring, consisting of oats and cool season peas, had the largest selection ratios. Cover crops may benefit wildlife by providing habitat before and after termination. Our findings will allow agricultural producers and wildlife managers in Kansas to make informed decisions on how to positively affect pheasant populations.

AUTHORS. Sprih Harsh, South Dakota State University; Dr. Andrew J. Gregory, Bowling Green State University

ABSTRACT. In South Dakota, ring-necked pheasant (Phasianus colchicus) hunting is a multimillion-dollar industry. Consequently, identifying concentrations of this species along with underlying causes for their spatial distribution is a priority for conservation and management. We used South Dakota Game Fish and Park’s brood survey data from 1993-2016 in an emerging Hotspot analysis framework in ArcGIS to identify areas that were consistently high (hotspot) and low (coldspot) pheasant productivity areas across that time period. We found that out of 89 locations which were part of this analysis, 26 locations were part of a hotspot in one or many of those years. We created a minimum convex polygon (MCP) for hot spot locations for each year and combined them together to have a single area with all the 26 points. This combined MCP was overlaid with a hexagon layer with each hexagon an area of about 2.59 km². To find out which part of this area were hot spots for how many years, we tallied the number of years that each cell was a hot spot. We then used Cropland Data Layer to categorize land cover and land use across different hot spots regions. We found the number of years a particular hex region was a Hotspot was positively associated with grassland area within the hex region and negatively associated with hex region area under row crop cultivation. We also quantified class and landscape level metrics within 500-m, 1000-m and 2000-m buffer for hotspot hex region routes using FRAGSTAT. We assessed relationship between brood counts and FRAGSTAT metrics using multinomial regression analysis. The abundance was found to be positively related to landscape configuration, area of grassland and area of row crop at small scale but with increase in scale some of these landscape metrics had a negative influence on pheasant counts.

AUTHORS. Nathan Holoubek, Rich Henderson, Jed Meunier - Wisconsin Department of Natural Resources

ABSTRACT. Tallgrass prairie, arguably the most fire-dependent system in North America, is a Biome that is exceedingly rare. Absent frequent disturbance, remnant prairie rapidly converts to woody plants. This creates unique challenges for conservation of prairie-specialist insects dependent on increasingly small and isolated habitats prone to direct and indirect threats from climate variability, habitat degradation, and management activities; or lack thereof. Regal fritillary butterflies (Speyeria idalia) are one example, with sharp population declines in recent decades and considerable disagreement on management practices, particularly the use of prescribed burning to maintain habitat. We evaluated regal fritillary populations within seven sites spanning a 20-year period (1997–2016) in relation to detailed fire, habitat, and climate records to better understand these interacting effects in relation to interannual and long-term population changes. Fire had short-term negative effects on regal fritillary abundance; however, habitat quality was one of the most important factors explaining populations and was positively associated with prescribed fire. Burning every 3 – 5 years maximized regal abundance; though even annual burning was more beneficial to regal fritillary populations than no burning at all. Our data suggests unburned refugia are important in maintaining populations, but creating and maintaining high quality habitat with abundant and varied nectar sources including violets (Viola spp) may be the most impactful management and conservation tool. Regals were consistently more than twice as abundant on high quality habitats and this relationship held across, and often dwarfed the effects of, various prescribed fire regimes or climate variability.

AUTHORS. Dan Salas, Cardno; Johanna Sievewright, American Transmission Company

ABSTRACT. Many pollinators are in serious decline in the United States and worldwide (IPBES 2016). As pollinator declines become acknowledged as a conservation concern, public and private entities are equally considering their role in pollinator conservation. American Transmission Company (ATC) has initiated its own pollinator protection program to address these concerns along the approximate 10,000 miles of rights-of-way they operate. As part of this program, ATC worked with Cardno to define priorities for landscape restoration and conservation across ATC’s transmission footprint. In doing so, ATC is adding to the conservation science of pollinator conservation by developing a better understanding, through models and field studies, of how landscape structure influences pollinators. This need for modelling and continued study is identified as a critical need for ecosystem service management (Kremen et al. 2007 as cited by Lonsdorf et al. 2009). To help ATC achieve their goals, Cardno developed the Pollinator Opportunities Within Rights-of-Way (POWR) model to help identify priority areas for pollinator habitat restoration and conservation as a tool to inform future management decisions related to pollinators. The focus of this effort was twofold: 1) identify and prioritize which areas of rights-of-way can be restored to create a landscape connection to other suitable habitat, and 2) which segments already support important habitat and should therefore be maintained or enhanced. The findings of this landscape conservation analysis yielded spatial priorities for conservation opportunities, helped define the roles of various transmission work activities in supporting pollinator habitat restoration, and allowed for targeted conservation actions.

AUTHORS. Joseph LaRose, University of Missouri; Lisa Webb, USGS Missouri Cooperative Fish and Wildlife Unit, University of Missouri; Deborah Finke, Division of Plant Sciences, University of Missouri

ABSTRACT. Tallgrass prairies and their obligate inhabitants once occupied a large swath of central North America, but now face the combined challenges of habitat loss and fragmentation. In Missouri, several hundred hectares of tallgrass prairie have been restored near patches of remnant native prairie. Typically, the success of reconstructed grasslands is assessed based on the extent to which native prairie plants have reestablished. Invertebrates are often assumed to colonize reconstructions if native vegetation returns. However, the limited mobility of many invertebrates and the isolation of many tallgrass remnants raises serious questions as to how prairie invertebrate communities in reconstructed prairies compare to those in remnants. To evaluate the effectiveness of prairie reconstructions in restoring grassland invertebrate communities, we sampled two guilds of terrestrial invertebrates: native bees (Apoidea) and grasshoppers (Acrididae). Both guilds include grassland specialists.  There are pollen specialists and rare kleptoparasitic bees found thus far only in remnant prairies in Missouri. The presence of those bees, and of several species of grasshoppers with limited mobility, on reconstructions would suggest successful prairie reconstruction.We sampled invertebrates from five conservation areas in Missouri containing tallgrass prairie habitat. Three areas contained prairie remnants adjacent to reconstructions, while the remaining two areas consisted of one remnant and one reconstructed prairie. We collected bees and grasshoppers in summers 2016 and 2017. We captured bees with bee bowls, and grasshoppers with sweep nets through standardized sweeps or targeted capture. Community analyses indicate that remnants and reconstructions may differ in composition for both taxa, particularly for grasshoppers. Reconstructed prairies were characterized by more mobile species, that are typically successful in agroecosystems Although not statistically significant, bee species richness and diversity were greater on remnant prairies than on reconstructions. For bees in particular, pollen specialists and kleptoparasites may be less capable of colonizing and surviving in reconstructed prairies. 

AUTHORS. Madison R. Rancour; Natasha J. Blomberg; Margaret A. Kuchenreuther, University of Minnesota, Morris

ABSTRACT. This study evaluates plantings of four mixes of native prairie forbs and grasses developed by the NRCS Bismarck Plant Materials Center with the goal of evaluating species establishment and attractiveness to pollinators. It also documents pollinator diversity in our region. In spring 2014 we planted two replicates of four pollinator mixes: 100%, 75%, 50%, and 25% prairie forbs mixed with native grasses. In summers 2015 and 2016 twice/week we walked a transect through each plot to count insects and note the plant species they visited. We also vouchered and identified insect visitors. Once/week we walked each transect to count flowers of each species in bloom. As the stand matured we observed an increase in natives, but by 2016 only 13 of 20 planted forbs had bloomed. In some plots we also observed strong establishment of perennial weeds, such as crown vetch and Canada thistle. The experiment attracted a wide variety of pollinators (123 morphospecies in 22 families), which often exhibited clear floral preferences. As the stand matured, honey bees and bumble bees shifted their preference from non-natives to natives. In both years small bees visited plots with higher densities of native forbs, and more often visited natives over weeds. Honey bees and bumble bees disproportionately preferred the mint species wild bergamot and anise hyssop, while small bees exhibited more generalist behavior. Plots planted with the highest percentage of native forbs attracted the most pollinators overall. Therefore, mixes should contain at least 50% forb seeds to ensure high attractiveness to pollinators, though 75% is even better. One complication in our analysis was a large difference in species establishment between replicate plots and extensive weed invasion in some plots. Therefore, a second conclusion is the importance of careful site preparation to eliminate perennial weeds and their propagules before establishing natives.

AUTHORS. Anson R. Main, School of Natural Resources - University of Missouri; Elisabeth B. Webb, U.S. Geological Survey, Missouri Cooperative Fish and Wildlife Research Unit; Keith W. Goyne, School of Natural Resources - University of Missouri; Doreen Mengel, Missouri Department of Conservation

ABSTRACT. Pervasively used as seed-treatments, neonicotinoid insecticides are widely applied across North American agroecosystems. Due to their high water solubility, neonicotinoids may be rapidly transported to adjacent field margins during precipitation events. Additionally, previous research demonstrates the potential accumulation of residues by non-target plant species. Unlike honeybees, numerous wild bee populations nest in the ground in close proximity to cultivated fields and flower foraging areas. To that end, it is unknown if native bee species are equally exposed to neonicotinoids through soil and non-target plants surrounding cropped fields (i.e., field margins). Few studies have evaluated neonicotinoid impacts on wild pollinator populations, including solitary and eusocial bee species (e.g., bumblebees). To evaluate the effects of neonicotinoid exposure on native pollinator abundance and diversity, we sampled 24 agricultural fields (treated and untreated) on four conservation areas in central and northern Missouri from pre-seeding to harvest in year 2016. At each field, we collected field and field-margin soils, sampled herbaceous and woody flowering species in field margins, and surveyed and collected a wide variety of native pollinators over time. Neonicotinoid residues were detected in field and field-margin soils during all sampling periods (frequency: pre-seeding, 58%; post-seeding, 67%; mid-growing, 69%; and, harvest, 58%). Clothianidin was the most-frequently detected active ingredient in field and margin soils with concentrations ranging from 0.16 to 55.7 µg/kg. Compared to untreated reference fields, native bee abundance was significantly less in both treated corn (ß = -0.72 ± 0.20, P = 0.002) and treated soybean fields (ß = -0.95 ± 0.28, P = 0.005). Here, we present our preliminary findings and discuss how this research improves our understanding of the potential impacts of neonicotinoid seed-treatment use on non-target native pollinator communities in agroecosystems.