Temperature increases due to climate change over the coming century will likely affect smallmouth bass (Micropterus dolomieu) growth in lotic systems at the southern extent of their native range. However, the thermal response of a stream to warming climate conditions could be affected by the flow regime of each stream, mitigating the effects on smallmouth bass populations. We developed bioenergetics models to compare change in smallmouth bass growth rate potential (GRP) from present to future projected monthly stream temperatures across two flow regimes: runoff and groundwater-dominated. Seasonal differences in GRP between stream types were then compared. The models were developed for fourteen streams within the Ozark-Ouachita Interior Highlands in Arkansas, Oklahoma and Missouri, USA, which contain smallmouth bass. In our simulations, smallmouth bass mean GRP during summer months decreased by 0.005 g g −1 day −1 in runoff streams and 0.002 g g −1 day −1 in groundwater streams by the end of century. Mean GRP during winter, fall and early spring increased under future climate conditions within both stream types (e.g., 0.00019 g g −1 day −1 in runoff and 0.0014 g g −1 day −1 in groundwater streams in spring months). We found significant differences in change in GRP between runoff and groundwater streams in three seasons in end-ofcentury simulations (spring, summer and fall). Potential differences in stream temperature across flow regimes could be an important habitat component to consider when investigating effects of climate change as fishes from various flow regimes that are relatively close geographically could be affected differently by warming climate conditions. K E Y W O R D Sbioenergetics, climate change, growth rate potential, smallmouth bass, water temperature 1

Multispecies occupancy models estimate dependence among multiple species of interest from patterns of co‐occurrence, but problems associated with separation and boundary estimates can lead to unreasonably large estimates of parameters and associated standard errors when species are rarely observed at the same site or when data are sparse. In this paper, we overcome these issues by implementing a penalized likelihood, which introduces a small bias in parameter estimates in exchange for a potentially large reduction in variance. We compare parameter estimates obtained from both penalized and unpenalized multispecies occupancy models fit to simulated data that exhibit various degrees of separation and to a real‐word data set of bird surveys with little apparent overlap between potentially interacting species. Our simulation results demonstrate that penalized multispecies occupancy models did not exhibit boundary estimates and produced lower bias, lower mean squared error, and improved inference relative to unpenalized models. When applied to real‐world data, our penalized multispecies occupancy model constrained boundary estimates and allowed for meaningful inference related to the interactions of two species of conservation concern. To facilitate the use of our penalized multispecies occupancy model, the techniques demonstrated in this paper have been integrated into the unmarked package in R programing language.

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Utilizing conservation genetics as a strategy for recovering the endangered Candy Darter (Etheostoma osburni) in West Virginia Brin Kessinger The Candy Darter (Etheostoma osburni) is a small freshwater fish native to the New River drainage in West Virginia and Virginia that was listed as endangered in November 2018. It has been extirpated from much of its historic range in West Virginia, restricting it to the Gauley and Greenbrier river drainages. In addition to extirpations, the species is threatened by introgressive hybridization with the invasive Variegate Darter (E. variatum). Previous research primarily focused on hybridization, but population genetic analyses were limited. Population genetic analyses aim to identify distinct populations through genetic structure and characterize the levels of genetic diversity amongst those populations. A series of reintroductions of wildcaught individuals from the Greenbrier River drainage was performed to create new populations that were not under threat of hybridization. Fish were stocked into Camp Creek and the Little Bluestone River in the Bluestone River drainage of southern West Virginia. Individuals from throughout the Greenbrier and Gauley River drainages along with the newly introduced individuals were genotyped with 12 microsatellite loci to assess their population structure and diversity. These results were used to make recommendations about conservation units and future reintroduction efforts. A watershed-level landscape assessment was performed on the Camp Creek and Little Bluestone River watersheds to compare the source habitat to the new habitat. There is strong evidence that the Greenbrier drainage population and the Gauley River drainage population are highly distinct and represent separate ESUs that should be treated as separate Recovery Units (RUs). The reintroduced population's genetic diversity captures the diversity of the source (Greenbrier drainage), but the landscapes of the new watersheds present some challenges to managers with higher levels of agriculture, resource extraction, and private land. The long-term persistence of E. osburni populations relies on continued monitoring and management of their genetics.