Insights into Steelhead Iteroparity in a Tributary of the Sacramento River, California

Oncorhynchus mykiss exhibit diverse and variable life history strategies, including both anadromous (steelhead) and nonanadroumous (rainbow trout) forms.  O. mykiss are iteroparous, or capable of spawning more than once before death.  Rates of iteroparity in steelhead vary between populations with greater frequency occurring in southern steelhead populations compared to northern populations and a lower frequency occurring in populations as distance from the ocean increases.  We will summarize information on rate of steelhead iteroparity gained through several research and monitoring projects in Battle Creek; including results from visual implant elastomer tagging, microsatellite genetic analyses, and otolith microchemistry analyses.