How telemetry can be used to better understand the ecology and inform management of freshwater fish in the Central Valley of California

Dr. Scott Colborne

Research Scientist, Michigan State University

Abstract

The Central Valley region of northern California is a biodiverse region of North America, but it also faces numerous ecological challenges. From persistent drought conditions to intense agricultural activities, the demand for freshwater resources has resulted in one of the world’s most heavily modified and managed water systems. This region is also home to several native species under severe threat of extirpation and, in some case, extinction. In this seminar, I will present research from two years of research with UC Davis using acoustic telemetry resources to understand the ecology of endangered green sturgeon that migrate hundreds of kilometers up the Sacramento River system to reach spawning grounds. In this project, we summarized over a decade of telemetry information compiled from multiple partners and government agencies to describe the migration timing of green sturgeon, including two distinct pulses of fish moving down the river after spawning – one group leaving almost immediately after the spawning period and another that remained in the river for almost 6 months after spawning. The second part of this seminar will shift from one of the largest fish found in this system to some of the smallest – Steelhead and Chinook smolts. These salmon species are at serious threat of disappearing from California and millions of dollars each year are spent on stocking efforts. I will talk about recent research to compare the migration timing and survival rates of these two species through the San Joaquin River system. Overall, this seminar is meant to demonstrate how telemetry techniques can not only reveal new details about the ecology of freshwater fish but also be used to aid conservation and management efforts for species of cultural and economic value.