Studying Fur Seal and Sea Lion Populations in Sunny Southern California - Blog Post 1

Okay, the title of this blog is a little misleading. Although we are currently working on San Miguel Island, which is a part of the California Channel Islands off of southern California, it is anything but sunny during a good part of the summer. We affectionately call this special place "the island of fog and wind."

The island lived up to its name last week. It took Heather Ziel (Polar Ecosystem Program) and me 4 days to make it here because the fog was too thick for the helicopter to land on the island. Last Friday (July 5), we joined our summer intern, Chris Moon, who had been working with Dr. Sharon Melin the previous 2 weeks. They were primarily hiking around the island looking for marked (branded and/or flipper-tagged) California sea lions. From re-sight data, we can learn about the survivorship, natality (adult females), and territorial tenure (adult males) for this species.

They were also able to witness peak pupping days for California sea lions, as thousands of pups have populated the beaches and coves of San Miguel Island. Since last Friday, our focus has shifted a little. Although we are continuing to look for marked sea lions, we are putting more efforts in finding tagged northern fur seals. Last week was when we would expect to see the highest number of adult females on the island at any one time, so this past week has been a good time to see many identifiable individuals.

Besides looking for and recording animals using binoculars and cameras, this past week we have included the use of uncrewed aerial systems (drones). Drones allow us to see individuals farther away or not easily accessible on the ground, without causing disturbance. Unfortunately, the fog and wind have restricted many of our flight plans.

This trip has been a reunion of sorts for Heather. She was a member of the California Current Ecosystem Program when she first started working at the Marine Mammal Laboratory. She now works with the Polar group on ice and harbor seals in Alaska. She was reminded of, and Chris is just experiencing, the diversity of wildlife on San Miguel Island. Six different pinniped species (including the California sea lion, Steller sea lion, Guadalupe fur seal, northern fur seal, northern elephant seal, and Pacific harbor seal) can be seen on the island during the year. Additionally, we frequently see two hybrids (California sea lion-northern fur seal and California sea lion-Guadalupe fur seal). Besides the diversity of pinniped species on the island, the number of animals is impressive, close to 100,000 total! There are a lot of blubbery bodies on the beaches of this island!

Apart from the marine mammals that live on San Miguel Island or are in waters offshore, the island is home to many other wildlife species including the island fox. It is the largest terrestrial predator on the island (about the size of a house cat) and has recovered from near-extinction with the help of a successful captive-breeding program. The program started around the time I started coming to the island of fog and wind more than20 years ago.

Stay tuned for Blog #2 where I will share more of our non-Alaskan (though at times it feels like we are in Alaska) adventures coming next week!