Mark Larson
The sea lion in Klopp Lake on Aug. 26.
My wife and I enjoy walking the trails at the Arcata Marsh and Wildlife Sanctuary, looking at and photographing the usual wildlife, but last Sunday, Aug. 25, around 10 a.m. at low tide, we saw something unusual. It appeared to be a stranded dead adult California sea lion lying covered in mud on the tidal flats just south of the Klopp Lake trail, with a large loop of tracks it had created.
I quickly shared a photo and reported the sighting to professor Dawn Goley, who heads the Cal Poly Humboldt Marine Mammal Stranding Program (MMSP), which investigates stranded marine mammals in Northern California.
Goley confirmed what we had seen as a dead-looking stranded male California sea lion, noting how unusual it was to see one this far up in Humboldt Bay. We agreed to meet up at Klopp Lake on Monday morning. But later that evening, my friend Rollie Lamberson posted his own photo of a very much alive sea lion upright on the mud flats around noon and another photo of that sea lion sitting on the Klopp Lake trail amid walkers.
Despite Monday being the first day of the semester for Goley, she met up with me around 9 a.m. to walk to the south shoreline of Klopp Lake. But the sea lion was not there. We joined two photography friends standing there who were also looking at the tracks of the sea lion in the tidal flat when two women walking by said they’d seen a sea lion swimming in the lake on Sunday morning. We debated whether there were two sea lions.
Eventually, we observed a sea lion gently surfacing to breathe about 50 yards offshore; its head and body would slowly sink under the surface of the water before slowly resurfacing. Goley gathered observations from onlookers about the sea lion’s recent locations and behavior. Her role, she explained later, “was to assess the sea lion from direct observation, gather reports from community stewards and colleagues, and work with marsh and city managers to collaboratively support public safety and to help alleviate stress to the sea lion.” Goley voiced safety concerns on the trail if the very large, agile sea lion reappeared there, and said she’d notify the North Coast Marine Mammal Center in Crescent City and the city of Arcata F.O.A.M. Interpretive Center staff.
Juvenile and adult male California sea lions travel from the Channel Islands to the North Coast to spend the fall, winter and early spring before returning to the Channel Islands to mate in the summertime. While California sea lions can be seen in Humboldt Bay, this is the first sighting of one in the Arcata marsh. Goley, who’s lived in the area since 1996, said she’d never seen or heard a report of a sea lion crossing the trail from the bay into Klopp Lake.
On Monday afternoon, the sea lion was resting in the water next to the shoreline in the shade of some bushes and I was finally able to get good photos of it. Later, I could see in the photos that the sea lion had what looked like three large numbers branded on its back in a triangle pattern: 0, 8 and a 6 or a 9.
I returned for the next few days to watch and photograph the sea lion from a distance and, like other observers, became concerned it did not look well. Late Wednesday afternoon, Goley walked by and joined me watching the sea lion passively resting in the water close by the shoreline, slowly surfacing to take a breath and then repeatedly submerging and re-surfacing, blowing bubbles as it cleared its airway.
Goley had reached out to various agencies to find out more about the sea lion using the ID numbers. She’d posted on social media, urging visitors "not to approach if it is on the trail and to maintain distance and limit disturbance when in the water. 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.”
Goley said NMMC staff had decided not to intervene with this wild sea lion visiting Klopp Lake, so long as he stayed in one place. She also expressed her own concerns about its health, given its passive behavior and condition of its skin. She planned to contact Emily Sinkhorn at the Arcata Environmental Services Department and North Coast Marine Mammal Center staff to see what needed to be done if the sea lion were to die in Klopp Lake.
On Thursday morning, my wife and I found the sea lion next to the shoreline in the southwest corner of Klopp Lake. We observed it passively surfacing and submerging and making a complete belly roll with big splashes from its front fins every 15 minutes or so. We also observed a yellow ID tag on one flipper. Enlarged, it revealed the letters OFW and a phone number, which I quickly shared with Goley.
After tracing the ID numbers, Goley posted on the F.O.A.M. Facebook page: “This adult 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 California sea lions in the Columbia River. These marks allowed scientists to track his movements and behavior over a large range and a long time period. After being marked in the fall of 2017, this sea lion was sighted as far north as British Columbia (2021) and (now) as far south as Humboldt Bay, California.”
Early Saturday, Aug. 30, in dripping fog at low tide, I walked east along the trail, seeing no new tracks or any evidence of a sea lion’s presence. But as I approached the southeast corner of Klopp Lake, a still object floated in the water not far from the shoreline. Through my telephoto lens in the misty fog, it looked like the side of the sea lion — the visible 0 sadly confirmed it was the same sea lion’s corpse. I texted the news and photos to Goley.
City staff and Goley immediately began brainstorming whether to remove the corpse from Klopp Lake due to possible deteriorating water quality, or to leave it there to decompose.
“I think there will be localized water quality issues, but not widespread or long term,” said Goley in an email. “Given that this is a naturally occurring event, Emily [Sinkhorn] at the city of Arcata and I are inclined to leave the carcass in place and let nature take its course. It might be interesting to monitor water quality if that is a concern to inform future responses based on that information.”
On Sunday, Goley shared her thoughts about this week’s experiences: “Although not surprised by the death of the sea lion, based on its behavior and declining condition, I was sad to see that this sea lion had passed. I gained an even deeper appreciation for the many stewards of the marsh I met while monitoring the seal lion's final days.”
Grim though it sounds, I look forward to photographing the decomposing corpse of the sea lion in Klopp Lake in the future and wonder what life forms — perhaps even a California condor — might appear to feed on it.
Goley offers this advice: “If you would like to report a sick or injured marine mammal, please contact the North Coast Marine Mammal Center in Crescent City 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."