Weber River Metapopulation and Source-Sink Dynamics of Native Trout and Nongame Fishes

Bonneville cutthroat trout (Oncorhynchus clarkii utah) presently occupy a variety of habitats from small streams to larger rivers and lakes that drain into the Bonneville Basin. As a result of continued threats to the subspecies and its habitat, the Bonneville cutthroat trout is designated by the State of Utah as a “conservation species” managed under a formal conservation agreement intended to preclude the need for listing under the federal Endangered Species Act. The Weber River in northern Utah is somewhat unusual for the intermountain west in that it is still home to native and endemic Bonneville cutthroat trout and bluehead sucker (Catostomus discobolus), yet is highly regulated and connectivity has been significantly reduced due to barriers to movement and migration. Despite the prevalence of these factors in the Weber River, both resident and fluvial Bonneville cutthroat trout as well as large, mature bluehead sucker were thought to be relatively common, highlighting the potential of this watershed for native fish conservation and restoration. The overall goal of this study was to identify the historical and contemporary importance of mainstem connectivity and tributaries to maintaining the population viability and persistence of these two species. To meet that goal, we used a multifaceted approach to describe the metapopulation structure and the importance of the tributaries in providing connectivity among subpopulations, at the watershed scale. This project was initiated in 2011 and the field work was completed in 2013