Spatial and temporal thermal trends of the lower Kuskokwim and Aniak Rivers, AK, USA

Adequate environmental data describing freshwater conditions (particularly temperature) that may influence Chinook salmon populations (which have had record low returns in recent years) are lacking. This ongoing project is using a combination of site-based temperature logger data and satellite imagery (MODIS and Landsat 8) to model continuous temperature data at two different scales, with the aim to identify thermal freshwater refugia for juvenile and adult salmon in the main Kuskokwim and Aniak Rivers. Adopting a standard for thermal data collection protocols for the Kuskokwim basin and important spawning tributaries could be used to understand changing temperature regimes, effects of temperature on salmon population dynamics, and identifying critical thermal refugia, all of which are important for managing subsistence fisheries. Our project seeks to employ a methodology having sufficient rigor that it can identify thermal regimes in critical habitats and at broad spatial and temporal scales, while also being cost effective. Modeling efforts are currently underway. Mean daily temperature data collected by all temperature loggers in the mainstem Kuskokwim and mainsteam Aniak Rivers, as well as floodplain habitats of the Aniak River (including beaver ponds, orthofluvial and parafluvial springbrooks) are provided here. Predicted temperatures and data from imagery will be published online when the project manuscript is published.