Western North American Naturalist Volume 76 Number 4 Article 4 12-31-2016 Habitat and fish assemblage associations and current status of northern leatherside chub Lepidomeda copei in western Wyoming Luke D. Schultz Wyoming Game and Fish Department, Pinedale, WY, [email protected] Peter A. Cavalli Wyoming Game and Fish Department, Pinedale, WY, [email protected] Hilda Sexauer Wyoming Game and Fish Department, Pinedale, WY, [email protected] David Zafft Wyoming Game and Fish Department, Laramie, WY, [email protected] Follow this and additional works at: https://scholarsarchive.byu.edu/wnan Recommended Citation Schultz, Luke D.; Cavalli, Peter A.; Sexauer, Hilda; and Zafft, David (2016) "Habitat and fish assemblage associations and current status of northern leatherside chub Lepidomeda copei in western Wyoming," Western North American Naturalist: Vol. 76 : No. 4 , Article 4. Available at: https://scholarsarchive.byu.edu/wnan/vol76/iss4/4 This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Western North American Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Western North American Naturalist 76(4), © 2016, pp. 427–440 HABITAT AND FISH ASSEMBLAGE ASSOCIATIONS AND CURRENT STATUS OF NORTHERN LEATHERSIDE CHUB LEPIDOMEDA COPEI IN WESTERN WYOMING Luke D. Schultz1,3, Peter A. Cavalli1, Hilda Sexauer1, and David Zafft2 ABSTRACT.—Human activities have extensively altered native fish assemblages and their habitats in the western United States. Conservation and restoration for long-term persistence of these fishes requires knowledge of their distribu- tional patterns and life history requirements. Northern leatherside chub Lepidomeda copei (hereafter northern leather- side) is a cyprinid native to the Snake and Bear River Basins of Wyoming, Idaho, Nevada, and Utah, and it is believed to have declined in distribution relative to historical records. To address information gaps in the species’ ecology and assess its status in the state, the objectives of this study were first to document the distribution (2010–2011) of northern leather- side in Wyoming and then to examine habitat factors related to the entire fish assemblage and to evaluate specific habitat associations of northern leatherside in the Bear River Basin, Wyoming. In the Bear River and Upper Snake River Basins, we documented the distribution of northern leatherside and compared it to the previously known distribution. Across the Bear River Basin, we used habitat measurements to assess abiotic features related to the distribution and abundance of northern leatherside. Northern leatherside was found across the Bear River Basin and was present in 2 streams each in the Upper Snake River and Green River Basins in Wyoming. Populations in Wyoming appear to represent the core of northern leatherside range, and our work provided a finer-scale delineation of the species’ occurrence. Northern leather- side was collected from a variety of habitats, but multivariate analyses and occurrence modeling indicated it was associ- ated with increased channel depth and depth variability, and positively associated with other native fishes (including mountain sucker Catostomus platyrhynchus, redside shiner Richardsonius balteatus, and speckled dace Rhinichthys oscu- lus). These findings on the distribution and ecology of northern leatherside provide important new information to assist successful management and conservation efforts within Wyoming and across the species’ range. RESUMEN.—Las actividades humanas han alterado significativamente las comunidades de peces nativos de agua dulce y sus hábitats en el oeste de Estados Unidos. La conservación y la restauración enfocadas en la persistencia a largo plazo de estos peces requieren del conocimiento de los patrones de distribución y de los requerimientos de las historias de vida. Lepidomeda copei es una especie nativa de los ciprínidos en las cuencas de los ríos Snake y Bear, en Wyoming, Idaho, Nevada y Utah, que se cree ha disminuido en relación con su distribución histórica. Para llenar huecos de información en su ecología y evaluar su estado de conservación, los objetivos de este estudio fueron, en primer lugar, documentar su distribución (2010–2011) en Wyoming y, posteriormente, estudiar los factores del hábitat relacionados con la comunidad de peces y asociaciones específicas del hábitat de L. copei en la cuenca del río Bear, en Wyoming. En las cuencas del río Bear y las cuencas del Upper River Snake, documentamos la distribución de L. copei y la compara- mos con la distribución previamente conocida. Al otro lado de la cuenca del río Bear, utilizamos medidas del hábitat para evaluar los factores abióticos relacionados con la distribución y la abundancia de la especie. Encontramos L. copei a lo largo de la cuenca del río Bear, y estaba presente en dos corrientes de las cuencas del Upper Snake y el río Green, en Wyoming. Las poblaciones de Wyoming parecen representar el núcleo de la distribución de esta especie, y nuestro trabajo proporcionó una escala más fina de la presencia de esta especie. Colectamos L. copei en hábitats muy variables, pero el análisis multivariado y el modelo de ocurrencia indicó una asociación con el aumento de la profundidad del canal y la variabilidad de la profundidad, y una asociación positiva con otros peces nativos (incluyendo Catostomus platyrhynchus, Richardsonius balteatus y Rhinichthys osculus). Estos resultados sobre la distribución y la ecología de L. copei proporcionan nueva e importante información que ayudará en el desarrollo de un manejo exitoso y en los esfuer- zos de conservación en Wyoming y a lo largo de su distribución. Due to the cumulative effects of overex- patterns, information on basic biology, an ploitation, habitat degradation, and interactions understanding of community and autecology, with introduced species, numerous western and an assessment of potential limiting factors native fishes are currently imperiled (Jelks et al. for the species (or assemblage) of interest 2008). Effective conservation efforts for these (Minckley and Deacon 1991). Though address- fishes require knowledge of distributional ing these information gaps has improved the 1Wyoming Game and Fish Department, Pinedale, WY 82941. 2Wyoming Game and Fish Department, 528 S. Adams St., Laramie, WY 82070. 3Present address: Forest and Rangelands Ecosystem Science Center, U.S. Geological Survey, Corvallis, OR 97331. E-mail: [email protected] 427 428 WESTERN NORTH AMERICAN NATURALIST [Volume 76 success of management actions for native to those of southern leatherside (Belk and sport fishes (e.g., salmonids of the genera Johnson 2007). Southern leatherside is usu - Oncorhynchus and Salvelinus; Dunham et al. ally restricted to lotic habitats below 2200 m 2008), conservation of native nongame fish has in elevation, is strongly associated with pools been hampered by a limited understanding of and other low-velocity areas (Wilson and their life histories and a general perception of Belk 2001), and is thought to have broad tol - these fishes as being undesirable (Cooke et al. erance for extreme environmental conditions 2005). Conservation and restoration of native (Belk and Johnson 2007). At the reach scale, fishes and ecosystems for long-term persis - southern leatherside is negatively associated tence can benefit from addressing these issues with brown trout Salmo trutta (Wilson and (Brouder and Scheurer 2007). Belk 2001). In the presence of brown trout, Northern leatherside chub Lepidomeda southern leatherside tends to occupy side- copei (hereafter northern leatherside) is a small channel refuge habitats, when they are avail - cyprinid native to the Bear River Basin in able (Walser et al. 1999, Olsen and Belk Idaho, Utah, and Wyoming and the Snake 2005). Loss of natural channel forms due to River Basin of Idaho, Nevada, and Wyoming habitat manipulation (e.g., channelization and (see UDWR 2009 for historical distribution dam/diversion construction) and degradation information). Although the species was origi - (e.g., riparian habitat impairment due to nally described to include populations of overgrazing) has been identified as poten - leatherside chub from southern Utah, recent tially contributing to decreased productivity molecular, morphological, and ecological evi - and fragmentation of northern leatherside dence supports designation of northern leather - populations (WGFD 2010). side and southern leatherside chub Lep - Conservation actions for northern leather - idomeda aliciae as separate species (Johnson side have recently been coordinated among et al. 2004). Across the range of both species, multiple state, federal, and nongovernmental leatherside chub have declined in distribution agencies (UDWR 2009). The conservation relative to historical records, have apparently agreement and recovery plan for northern been extirpated from numerous locations leatherside coordinated the conservation across their range, and are highly fragmented efforts of several state and federal agencies in areas of persistence (Wilson and Belk 2001, and targeted areas of management action, Belk and Johnson 2007). Jelks et al. (2008) including habitat protection and enhancement, included both species on their list of imperiled restoration of natural hydrologic conditions, freshwater fishes of North America and and control of nonnative