November 1st: A655

Sea Lion of the Month

The Sea Lion of the Month for November is a A655! We wanted to feature a marked sea lion that has an interesting story but is also a good example of pretty typical sea lion behavior. So far, you all would not have seen him on Steller Watch since you’re looking through images from 2015 and later. A655 was spotted in our remote camera images well before that.

But, lets start at the beginning:


Our featured sea lion was born and marked on Ugamak Island, which is one of the other of many locations where we mark sea lions. Upon the time of capture on June 25, 2009, A655 weighed almost 60 Ibs (26 kg) and was 3.5 ft (106 cm) long. Not the largest pup we have seen but he is quite the explorer! After the summer of 2009, we did not see A655 until 2012 in the remote camera images. Volunteers in our office saw him on images captured at Cape Wrangell throughout the summer and early fall of 2012. We also saw him here in person during one of our summer research cruises in 2013.


The next time he was spotted was all the way at Round on Walrus Island in Bristol Bay in May of 2014–that’s almost 5,000 miles (8,000 km) away! He hung around here until the following spring returned home to Ugamak Island in June of 2015. Over the next winter he headed back up to Bristol Bay and was seen at Round (Walrus Island) and Cape Newenham in spring of 2016, returning once again to Ugamak Island the following summer of 2016. It’s possible he realized he wasn’t quite ready for rookery life during the summer breeding season because he took off at the end of June and didn’t return the following summer. He definitely wasn’t looking like a young juvenile anymore (see image below) so I’d imagine some of the territorial adult males, or bulls, weren’t wanting him around.

A655 playing in the water with other young males at his birth place, the rookery on Ugamak Island

We have no sightings of him over winter but biologists Katie Luxa and Katie Sweeney saw him at Cape Morgan on Akutan Island during their re-sight trip this past summer of 2017. This time he was hanging out at the ‘haulout’ part of this rookery site. The haulout part of the site is where we see mostly young and sub-adult males hanging out. We tend to think of this as the “bachelor beach” because these males aren’t large enough to compete with territorial bulls on the main rookery part of the site (where a majority of the breeding and pupping happens).

A655 hanging out at the bachelor beach on Cape Morgan on Akutan Island

The movements of A655 really shows us typical behavior of Steller sea lion males. They tend to wander great distances during their younger years until they’re ready to return to their natal rookery, or rookery where they were born, to compete for a breeding territory. Lucky for us, his journey brought him all the way to the Aleutian Islands. Keep your eyes peeled, you may see another great wanderer with a very different letter or symbol than the usual ~ or >.

Curious about other pinnipeds (seals and sea lions)? Check out our neighbors in the Pacific Islands to the south, the monk seals of the Northwest Hawaiian Islands. The Pacific Island Fisheries Science Center features their own Monk Seal of the Month!

We will share the story of one marked sea lion each month. Be sure to check our Sea Lion of the Month page on the 1st of every month to learn about our featured Steller sear lion. You may nominate a sea lion by submitting their full mark on the Sea Lion of the Month nomination forum. Thank you all for your nominations!