Interagency Pacific marten (Martes caurina) distribution study on the Olympic Peninsula, Washington

The objective of this study was to determine if the Pacific marten (Martes caurina) still occurs on the Olympic Peninsula in Washington State. We reviewed recent records of marten observations on the Olympic Peninsula since 1998, and conducted new surveys in undersampled regions of the Olympic Peninsula during summer, 2016. We reviewed evidence of fisher presence from 6 previously reported studies of carnivore distribution and presence on the Olympic Peninsula and conducted new surveys in previously undersampled areas of the Peninsula. We documented five highly reliable records of marten observations on the Pensula since 1988. Further, we established 197 camera stations in search of martens, amassing a total of 17,897 camera-nights of survey efforts in previously undersampled regions. We documented presence of one additional marten during summer 2016. This marten, however, was close to a marten detected in 2015, so it was not clear if it represented a different marten. We concluded that five to six martens have been verified present on the Olympic Peninsula since 1988. Pacific martens appear to be very limited in distribution and at critically low numbers throughout much of their former range on the Olympic Peninsula.