Bearing-tree data were used to calculate an index, pyrophilic percentage, depicting the importance of fire before Euro-American settlement on three landscapes, two within the Prairie Peninsula and one outside the region. Based on functional traits, bearing trees were classified as either pyrophilic or pyrophobic, applied to Public Land Survey points, and the pyrophilic percentage was calculated for each point. Kriging was applied to this point database to create a continuous surface of pyrophilic percentages. Regression analysis was used to relate this surface to environmental factors. Regression models created separately for each study area explained 38 to 53% of the variation in pyrophilic percentage. A positive association between pyrophilic percentage and distance to water and summer potential evapotranspiration was consistent across all study sites. The consistently high values and spatial patterns of pyrophilic percentage revealed fire-dominated landscapes interspersed with patches of pyrophobic vegetation. The restriction of pyrophobic areas to the leeside (east) of waterbodies indicated these served as firebreaks in a fire-swept landscape. Lake Michigan must have had a profound effect on pre- Euro-American settlement fire environments, serving as a massive physical firebreak while casting a moist maritime climate eastward. In southern and southwestern Illinois, the Mississippi River and associated tributaries along with an increase in topographic complexity also served as firebreaks, with pyrophobic forests restricted to riparian zones which progressively graded to pyrophilic vegetation on surrounding uplands. Our analysis expands the use of Public Land Survey data by converting bearing trees into a meaningful fire ecology index. While much of the landscape included in our study area is now in agriculture or urbanized, pyrophilic percentage maps can help guide land managers in the application of fire for restoration, conservation, and forestry purposes.

Wildlife conservation and management requires an understanding of patterns and changes in the populations and distributions of wildlife. Moose (Alces alces) population trends vary within regions of North America, such as in the upper Midwest region of the United States where sub-populations are declining in Minnesota, but are stable or increasing in Michigan. The population and distribution of moose in Wisconsin, which shares a border with Minnesota and Michigan, is unknown. We examined community scientist observations of moose collected by the Wisconsin Department of Natural Resources from 1991–2017 to determine the trends of moose occurrence in Wisconsin and the relationship to potential drivers. We used a binomial generalized linear mixed model in a Bayesian framework to understand how variables affect county-level occurrence of moose. We found moose occurrence was greater in counties closer to Minnesota and Michigan, but the effect of distance to Minnesota on moose occurrence has decreased over time. We also found counties with higher habitat suitability and proximity to Michigan are more likely to have a moose occurrence than those with low habitat suitability. This study offers insight for moose populations at the southern fringe of their circumpolar distribution and a foundation for understanding the moose population in Wisconsin and the upper Midwest.

American martens (Martes americana) are typically found in late-successional forests with closed canopy cover and high structural diversity. Reintroduced populations of martens in the Northern Lower Peninsula of Michigan inhabit areas that are devoid of many of these features, which may impact their prey base. The goal of our study was to evaluate the small mammal prey base available to martens in the Northern Lower Peninsula. To assess prey availability, diversity, and composition, as well as effects of trap type and habitat features on trapping success, we sampled 24 study plots within the Manistee National Forest for small mammals in 2013 (n=24) and 2014 (n=20). Study plots were situated in four habitat types: conifer, deciduous, mixed conifer-deciduous, and mixed oak. Total capture rates were significantly and positively associated with relative deciduous tree cover. This result highlights how managing tracts of land for small mammal prey base may overlap with goals set forth by researchers for marten habitat needs (e.g., resting site preferences). We found large Sherman traps had significantly higher total capture rates than other trap types (medium Sherman and pitfall traps), and we recommend researchers use a variety of trap types to maximize detectability of small mammal species diversity and richness.

Lesser Prairie-Chicken (Tympanuchus pallidicinctus) populations have declined throughout most of their distribution since the mid-1980s. These declines are largely attributed to loss of habitat through the conversion and expansion of cropland, construction of oil wells and other anthropogenic features on the landscape, and grazing intensification. Changes in habitat availability and quality are seemingly having a disproportionate effect on the reproductive habitat of Lesser Prairie-Chickens, as some populations continue to decline. Nest and brood survival are crucial to population growth of Lesser Prairie-Chickens, with adequate reproductive habitat vital to population persistence. To better understand the influence of reproductive habitat availability on populations, we quantified the composition of reproductive habitat in lek landscapes across the northern extent of the Lesser Prairie-Chicken range. We measured vegetation at six study sites in Kansas and Colorado from 2013–2016. We sought to quantify available nest and brooding habitat adjacent to leks, investigate the relationship between reproductive habitat availability and lek attendance by males at several spatial scales, and examine vegetation characteristics that influence lek attendance. Within 5 km of a lek, 25% (2546/10,320 points) and 26% (2682/10,320 points) of random locations provided nesting and brooding habitat, respectively. Changes to reproductive habitat at both scales affected male attendance at leks. Visual obstruction of vegetation was the main predictor of male lek attendance at both spatial scales and limited the amount of reproductive habitat in lek landscapes. Accordingly, management should increase visual obstruction throughout the Lesser Prairie-Chicken range to increase reproductive success and improve populations to facilitate achieving the conservation goal set by the Western Association of Fish and Wildlife Agencies of a 10 y average Lesser Prairie-Chicken population of 67,000 birds.

The recently delisted black-capped vireo (Vireo atricapilla, hereafter “vireo”) nests in shrublands from south-central Oklahoma to southwestern Tamaulipas, Mexico. Vireos are considered to be “conservation-reliant” because they require on-going habitat maintenance and control of brown-headed cowbirds (Molothrus aster, hereafter “cowbird”). Most long-term research has been conducted in comparatively mesic parts of the vireo range, but more arid shrublands comprise the larger proportion of their distribution. Our study area is in a Nature Conservancy preserve in southwestern Texas (Val Verde County), which does not manage vireo habitat or cowbird populations. We examined change in habitat characteristics (2002 vs 2017) and bird detections (1997-2001 vs 2013-2017) at two sites: a mesic alluvial terrace and an adjacent semi-arid canyon. The alluvial site is recovering from a historic flood in the 1950s that scoured vegetation to bare ground; the canyon site has not experienced any major disturbance in that time frame. Vireo and cowbird detections declined at the alluvial site but not at the canyon site. Several important vegetation characteristics of the alluvial site changed significantly: density of leaf cover at lower heights (<1 m) decreased, the number of shrubs increased, and tree height increased. At the canyon site, leaf density increased in all height classes above 0.5 m, shrub width increased, and the number of shrubs increased. While the alluvial site has become less suitable for vireos, the canyon site has supported breeding vireos throughout our study period despite lack of landscape management or cowbird control. Our data suggest that in more arid parts of the vireo range, undisturbed shrublands persist as mature viable habitat for extended periods, possibly in perpetuity, with little or no need for management. These low-maintenance shrublands will be especially important for the long-term persistence of black-capped vireo populations.

Distinguishing Black Bullhead (Ameiurus melas) from Brown Bullhead (A. nebulosus) can be difficult, in part, due to conflicting evidence regarding reliable meristic and morphological characters with which to base identifications. The possibility of hybrids with intermediate traits further complicates diagnosis. Identification guides have typically focused on adults, leaving guidance for juveniles largely undescribed. We compared morphological identifications of Black Bullhead and Brown Bullhead with a cytochrome c oxidase I (COI) barcode and microsatellite assignments. Specifically, we examined: (1) gill-raker count, (2) anal-fin ray count, (3) prominence of pectoral-spine serrae, (4) DNA barcoding using the COI gene, and (5) cluster analysis of nine microsatellite loci. With the exception of anal-fin ray counts, we found a high degree of agreement among all methods. Microsatellite analysis identified two clearly distinct genetic groups, and these groups corresponded to individuals identified as Black Bullhead and Brown Bullhead based on morphology. Although Black Bullhead and Brown Bullhead did not share COI haplotypes (except for one individual), we found greater intraspecific genetic distances among individuals identified as Brown Bullhead than between Brown Bullhead and Black Bullhead, demonstrating that caution is warranted against using COI haplotypes as a barcode to solely distinguish the two species. Pectoral-spine serrae prominence was a useful character to distinguish the two species and worked especially well on individuals <125 mm total length. Gill-raker counts of euthanized fish in the laboratory were appropriate for the identification of all sizes of Black Bullhead and Brown Bullhead (using the lowest number of gill rakers on the first gill arch if asymmetry was observed). Finally, microsatellites did not show evidence of recent hybridization at our sampling sites. We recommend using pectoral-spine serrae prominence to distinguish between Black Bullhead and Brown Bullhead in the field and using gill-raker counts for laboratory based identification.

Hybridization among gar species (Pisces: Family Lepisosteidae) has only recently been documented, and relatively few occurrences have been reported. In the Fox River drainage of the Lake Michigan Basin in Wisconsin, apparent hybrids and introgressed individuals (hereafter “hybrids”) of Longnose Gar (Lepisosteus osseus) and Shortnose Gar (L. platostomus) were widespread and numerous, constituting about 44% of the total gar population. Presumed hybrids could be readily distinguished by either their intermediate ratio of snout length to snout width or a low ratio, characteristic of Shortnose Gar, coupled with the presence of conspicuous spots on the top of the snout, an occasional Longnose Gar characteristic. Presumed hybrids had genetic matrilines (cytochrome b) of either Shortnose or Longnose Gar. Apparent hybrids occur commonly throughout the Fox River drainage, including the upper and lower Fox River, its major tributary the Wolf River, the riverine lakes Poygan, Winneconne, Butte des Morts, Winnebago, and Little Butte des Morts, and Green Bay, Lake Michigan, near the mouth of the lower Fox River. Evidence exists for possible hybrids in the adjacent Mississippi River basin and the Missouri River basin, but they appear to be less common and more localized. Extensive hybridization and introgression in the Fox River drainage may have been facilitated by the close phylogenetic relationship of Longnose and Shortnose Gar, the much greater abundance of Longnose relative to Shortnose Gar in the Fox River drainage, the apparent relatively recent colonization of the Fox River drainage by the Shortnose Gar, and the substantial modification and loss of gar spawning habitat in the Fox River drainage caused by dams and artificial water level regulation.

Synthyris bullii (Plantaginaceae; Besseya bullii; kittentails) is a rare endemic of the Midwestern U.S.A. Although seed germination studies have been conducted for this species, limited information is available regarding seed viability after prolonged seed storage. The main goal of this study was to re-assess seed germinability of Synthyris bullii seeds collected from 2008 to 2011 across its range. Overall, we found regardless of seed age, locality (i.e., site and state), and maternal environment (i.e., open, semi-shaded, and shaded) seeds are still viable. Although values were low for seed germination and seedling survivorship, the results of this study are encouraging and point to seed harvesting and storage as one way to preserve this species.

Patterns of maternal expenditure in Plains bison (Bison bison bison) are equivocal, with different studies yielding conflicting results. Therefore, our objective was to investigate the unsettled question of differential maternal expenditure in Plains bison. By observing the nursing behavior of known age calves, we measured post birth maternal expenditure on sons and daughters between birth and 3 mo of age. Calf weights at 6 mo of age also were measured. Because male calves grow faster and are larger than females as adults, we predicted sons would attempt to acquire more energy via differential nursing behavior and would be heavier at 6 mo of age. The results of our t-tests revealed no significant differences between sons and daughters in any nursing behavior. Male calves, however, performed all behaviors approximately 12% (range 8–20%) more frequently than female calves. For example, despite the nursing attempts of sons being rejected nearly 13% more often than that of daughters, sons nursed about 10% more frequently and 9% longer than daughters did. This occurred despite mothers terminating nursing bouts equally for both sexes. Therefore sons appear to demand (and obtain) more energy from mothers than daughters.

The genus Corbicula contains one of the most common and successful aquatic invasive species to North America. Prior to 2015 two predominant species of Corbicula were known from the United States—C. fluminea and C. largillierti, referred to as Forms A and B, respectively. Form A has spread throughout most of the U.S., while Form B is mainly contained in the Midwest and southern U.S. In 2015 a novel Corbicula, known as Form D, was discovered in the Illinois River, at Marseilles, Illinois, and was later reported from the Ohio River. Our primary objective for this study was to report additional records of Form D, with a focus on the upper Illinois River watershed. Surveys during summer 2017 verified the presence of Form D in the Tennessee and Mississippi rivers, as well as multiple new locations in the Des Plaines and Illinois rivers, where all three Corbicula forms co-exist.