Inland waters provide valuable ecosystem goods and services and are intrinsically linked to downstream coastal areas. Water quality impairments that lead to harmful algal blooms damage valuable commercial and recreational fishing economies, threaten food security, and damage already declining native species. Prymnesium parvum is a brackish water golden alga that can survive in salinities less than 1 ppm and when it blooms it can create toxins that kill aquatic life. Blooms have been documented globally including 23 U.S. states. We report a case study of an aquatic life kill associated with P. parvum in Dunkard Creek (WV-PA, USA), in the Ohio River Drainage. We document the immediate impact to aquatic life and responses of the aquatic community ten years post-kill. Most fish species returned within a year. Excellent connectivity to unimpacted tributaries and a river downstream likely aided the reestablishment of most species, although some had not reached pre-kill abundances after ten years. Mussel taxa did not recover despite significant efforts to relocate adult mussels and stocking of host fish inoculated with glochidia; probably due to other water quality impairments. Given the potential for lateral transport of P. parvum via industry and natural vectors we conducted an ecological risk assessment mapping the spatial extent of U.S. waters that could be threatened by golden algae colonization and blooms using a national water quality database and a state database. Overall, about 4.5% of lotic systems appeared to have some level of risk of harboring P. parvum, making them at risk for potential golden algae blooms in the face of increasing salinization and eutrophication of freshwaters.

Species-specific length-weight relationships can inform researchers and managers about the growth patterns and health of fish populations. Few length-weight relationships exist for Appalachian stream fish species despite the high amount of biodiversity within the region. The main purpose of our study was to determine the length-weight relationships for stream fish species found in Central Appalachia. We sampled 16 streams and captured over 14,000 individual fish among 44 species. We identified each fish to species and recorded total length (mm) and weight (g) for each individual. These data were log₁₀ transformed and analyzed using linear regression to calculate the length-weight parameters for each species. Relationships were calculated for 44 different stream fish species. Searches in FishBase.org revealed that of the 44 species in our data, 9 species have no current data in FishBase.org (Froese and Pauly, 2016), while 20 others have no previous representation from Central Appalachia. The relationships obtained in this study are some of the first published for these species in this region. Availability of species- and region-specific data on length-weight relationships could help inform future research and management of these species.

Florida bass (Micropterus salmoides) and largemouth bass (Micropterus nigricans) are iconic sport fish that hybridize readily, influencing fishery management practices. While the Florida bass has been introduced to various U.S. states to create trophy fisheries, its genetic introgression into native populations can lead to ecological and genetic consequences. Recognizing the need to assess Florida bass presence to guide future management directions, diagnostic SNPs were genotyped for 856 putative largemouth bass across 31 sampling locations across the state of West Virginia. Florida bass controls and a reduced representative sample of 226 individuals from 19 sampling locations were sequenced using the genotype-by-sequencing dd-RAD protocol. The results from the two genomic investigations found no Florida bass ancestry in West Virginia populations, suggesting either no introduction or failed reproductive success of Florida bass in the state. Among West Virginia largemouth bass populations, unique genetic ancestries were found predominantly in introduced non-native largemouth bass populations, indicating that the only sub-structuring in the state is a result of stocking non-native ancestries into the state. Genomic diversity was found to be higher in Ohio River pools compared to inland reservoirs, as well as showing higher levels of potential inbreeding. These results underscore the need to preserve the genetic integrity of native Ohio River strain largemouth bass and prevent the introduction of the Florida bass or F₁ hybrids into the Ohio River and other watersheds of West Virginia. Management recommendations include prioritizing the stocking of native strain bass to mitigate inbreeding and avoid introducing Florida bass to conserve genetic diversity.