An adult male California sea lion was reported to the Cal Poly Marine Mammal Stranding Program by Mark Larson on the mudflats adjacent to Klopp Lake trail at the Arcata Marsh on Sunday morning, 25 August.  Since the initial sighting, the sea lion has moved between the tidal flats near the trail and Klopp Lake.  California sea lions are common off our coastline during this time of year and can be seen visiting the Bay, but they rarely venture this far up the bay.  The North Coast Marine Mammal Center and the Cal Poly Humboldt Marine Mammal Stranding Program are monitoring the animal and we encourage the public not to approach if it is on the trail and to maintain distance and limit disturbance when in the water.

This sea lion was marked by the Oregon Department of Fish and Wildlife in Astoria, Oregon in 2017 as part of a routine marking project in Astoria studying the foraging ecology and movements of CSLs in the Columbia River.  These marks allow scientists to track his movements and behaviour over a large range and a long time period.  After being marked as an adult in Astoria in the fall of 2017, this sea lion traveled as far north as British Columbia (2021) and (now) as far south as Humboldt Bay, California (ODFW).

Tips for navigating around this animal - Please turn around if this animal is on land either near or on the trail.  Sea lions can be aggressive if approached and can move surprisingly quickly.  If it is in the water near shore, please minimize disturbance.  Thank you for your help.

If you would like to report a sick or injured marine mammal, please contact the North Coast Marine Mammal Center at 707-951-4722.  If you would like to report a dead stranded marine mammal please contact the Cal Poly Humboldt Marine Mammal Stranding Program at marinemammals@humboldt.edu or 707-826-3650.

Written by Dawn Goley - Cal Poly Humboldt Marine Mammal Stranding Program - Photos by Mark Larson