Applications of life history and fisheries data for improved management of skates

Start/End: February, 2018 to February, 2020

A commercial skate fishery has operated in California waters for nearly 100 years, but the status of targeted populations and the species composition of historic landings are unknown. Recent concerns regarding overfishing of the Big Skate off the Pacific Northwest and anecdotal evidence of declines in California populations of Big and California Skates have focused management attention on these species and the commonly co-occurring Longnose Skate. The National Marine Fisheries Service is expected to conduct stock assessments on at least two and possibly all three of these species during 2019.

Using data that were collected on Big, Longnose, and California skates off central California during the 2000s, researchers will estimate critical life history information such as sex-specific size and age at maturity, longevity, and reproductive seasonality. They will use this information to determine the absolute and relative contribution of life-stage specific demographic parameters to overall population growth. A concurrent study will develop catch reconstructions for Big, Longnose, and California skates based on California Department of Fish and Wildlife fishing block and fish ticket data, a procedure that has been vetted for other California groundfishes.

Successful completion of these complementary studies will be of considerable importance in improving stock assessment models, and developing a more complete understanding of past and future effects of fishing on California skate populations.