A stakeholder-supported conservation assessment for a data-limited species: Olympic mudminnow (Novumbra hubbsi)

Olympic mudminnow (Novumbra hubbsi) is the only endemic freshwater fish species in Washington State and is limited to south-western and northern coastal wetlands there. Population decline has led to its listing as state 'Sensitive', while recent genetic analysis has identified north coast populations as a sub-group of potential concern because of historical isolation and low level of occurrence. Substantial knowledge gaps about the species have made further assessment of conservation status difficult and hampered proactive conservation measures. This article describes a three-tiered approach to evaluate conservation status, comprising: (i) a set of high-priority research questions identified by experts and stakeholders to advance conservation knowledge; (ii) a habitat suitability model to identify environmental factors related to the presence and absence of the species; and (iii) synthesis of information from that suitability model and other research to evaluate status using IUCN Red List criteria. Together these components provide an initial research agenda to guide future management and monitoring. Evidence for an elevated conservation status of Olympic mudminnow across its entire range is mixed, with knowledge about changes in distribution and population over time lacking in many places. The case for enhanced conservation status is strongest for the genetically distinct populations along the northern coast, where suitable habitat is limited and populations highly disjointed. Development of a monitoring network that would detect changes in distribution and abundance of key populations is a central requirement for the conservation of the species, which is threatened by the effects of climate, land use change and invasive species. Involving stakeholders in conservation planning at early stages allows development of robust, practical research questions based on shared data and diverse expertise. This is particularly valuable where species knowledge is highly constrained. These elements produce confidence in implementing research and management actions that are more likely to gain wide acceptance and increase knowledge of conservation status and needs over time.