Steller’s Sea Lions are declining in many parts of their range, but they seem to be thriving in Southeast Alaska, especially in Glacier Bay and Icy Straits. A group of ten of Naturalist Journeys, LLC travelers recently observed them on a recent nature tour to the region.
The tour was promoted as a land-based “Un-cruise Option to Southeast Alaska”, wanting a more intimate experience with wildlife than a 1400 passenger or larger cruise ship could provide. Based out of a lovely Inn at the edge of Icy Straits, the group spent a lot of time in small boats, allowing for close encounters with wildlife as they zipped (carefully!) around the vast and stunning waters of Icy Straits. Humpback Whales were close companions each day.
Here is a report first hand:
On the day we chartered small fishing boats to take us over to Chichagof Island and Elfin Cove, we passed by one of several haulout areas used by Steller’s Sea Lions. These impressive marine mammals are pinnipeds, the name given to a diverse group of fin-footed mammals that includes walruses, eared seals (sea lions and fur seals) and earless or true seals, this last subgroup the category for Harbor Seals. Two pinnipeds regularly occur together in Southeast Alaska, Steller’s Sea Lions and Harbor Seals. Steller’s populations are on the rise (about 3.2% population increase per year according to Glacier Bay National Park biologists) while Harbor Seals have seen a dramatic decline (a 75% population loss since the 1990’s, continuing at about 5% a year).
Several of our group had been to other parts of Alaska before, and remembered large numbers of Harbor Seals that rested on ice chunks and bergie bits (small icebergs) below calving glaciers near Seward. This headwater habitat seemed to be a safe place for them, as Orca rarely ramble up long, narrow fjords to this realm of ice. In the last few years, scientists are keeping a watch on something thought to be uncommon – predation by Steller’s Sea Lions on juvenile Harbor Seals, an event witnessed by Glacier Bay National Park staff in 2010, and reported in the journal Aquatic Mammals, Volume 36, No. 2, pp. 129-132. Part of our not seeing them may be explained by timing, their numbers peak in June to pup, and August to molt, whereas we were there mid-July. But it also may have something to do with increased predation. Steller’s Sea Lions are known to be primarily piscivorous (a nice twist of words to say fish-eating…), but they share that feeding niche with whales, and seabirds. Glacier Bay and Icy Straits have witnessed dramatic landscapes in the last 225 years, due to the dramatic retreat of tidewater glaciers. Might a change in diet for Steller’s Sea Lions signal something is changing in the sea and its resources, once again?
Naturalist Journey’s guide Peg Abbott caught this shot of one of Icy Bay’s “bad boys” while on tour in July. Next year’s journey will depart in early August – find details at www.naturalistjourneys.com
Read more about Steller’s Sea Lions and Harbor Seal Predation
Read more about Naturalist Journey’s recent trip to Icy Straits and Glacier Bay in Southeast Alaska (link to Trip Report coming soon!)
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