PSI’s lead ecosystem ecologist Tessa Francis is co-author of a 2017 paper linking increasing adult mortality of Puget Sound herring with regional population declines in the species. The authors report that natural mortality among herring four years and older has doubled in Puget Sound since 1973, suggesting a possible connection to declines at spawning sites near Cherry Point and Squaxin Pass. Age structure has been shifting in Puget Sound herring populations for the past 30 years, their analysis shows, which could have negative impacts on both herring and their predators.
The article is published in the ICES Journal of Marine Science and is co-authored by Margaret Siple (lead author) of the School of Aquatic and Fishery Sciences at the University of Washington (UW SAFS), Andrew Shelton of NOAA Fisheries, Tessa Francis of PSI, Dayv Lowry and Adam Lindquist of the Washington Department of Fish and Wildlife, and Tim Essington of UW SAFS.
Margaret C. Siple, Andrew O. Shelton, Tessa B. Francis, Dayv Lowry, Adam P. Lindquist, Timothy E. Essington; Contributions of adult mortality to declines of Puget Sound Pacific herring, ICES Journal of Marine Science, , fsx094, https://doi.org/10.1093/icesjms/fsx094