Cruisin’ to Berners Bay

in search of an annual wildlife congregation

Every year, Juneau Audubon offers several spring cruises to Berners Bay, not far north of town. There is always a hope that the cruise might happen to arrive in the bay during the time when the hooligan (=eulachon=candlefish=salvation fish) are running. this is hard to do, because the hooligan spawning run is short, only a week or two, and the timing varies from year to year—and it may be getting earlier than it was a few years ago.

When the hooligan come in, they mill about in the bay for a while, and that’s when the marine mammals enjoy a feast. Whales pass through, and seals hang out on a reef near Slate Cove. Steller’s sea lions stock up on the fatty little fish before heading out to their outer-coast rookeries for pupping and mating. On the rookeries, males don’t feed for several weeks, being busy defending harems and mating; females give birth and nurse the newborns, which costs them a lot of energy—so putting on some fat ahead of all that activity is essential. Years ago, when we studied the predators at hooligan runs, we counted over two hundred sea lions in the bay on some days, making a racket and leaving hooligan-grease slicks on the water.

Hooligan spawn in the lower reaches of the glacial rivers that enter the bay, and sometimes the seals and sea lions follow their prey up-river. It was quite a sight to watch a big bull sea lion humping hastily over the sand bars to reach deeper river waters and the up-running spawners.

thayers-gull-with-eulachon-by-bob-armstrong
A Thayer’s Gull with eulachon. Photo by Bob Armstrong

Birds come to the spawning run in droves. White clouds of over forty thousand gulls would be calling, chasing, pirating fish from each other, loafing on the sands. Eagles lined the river banks—we estimated that there could be a thousand or so. Local ravens and crows scavenged hooligan that were stranded by out-going tides and stashed their prey in the grass or fed them to chicks in the nest. Even dabbling ducks, such as mallards, chowed down moribund hooligan.

In some years, herring also spawn in the bay about the same time as the hooligan run. Herring spawn on the seaweeds along the rocky shores and attract hordes of egg-eating scoters and gulls, along with eagles interested in the fish themselves.

It was all very exciting! But, as a naturalist aboard the cruises this year, I had to tell folks to imagine all that predatory excitement. It seemed as if the hooligan run was over, although gulls still hung out along the edges of the river mouths. We heard rumors that the herring were in, and getting ready to spawn, but it didn’t seem to be happening just yet.

While it was a bit disappointing, perhaps, to miss the big show, I suspect that the folks on board were not unhappy at all. We saw a fine display of “pec-slapping” by humpback whales: whacking the water with powerful slaps of their long pectoral fins. The pectoral fins of humpbacks are longer, relative to body size, than those of other whales. Those mighty pecs are reportedly used to herd small fish, in fighting off attacks by orcas, and in making a swimming whale very maneuverable. They may also be used as some kind of display (still to be studied), and male humpbacks sometimes use them as props for their headstand posture while they sing during the mating season in winter.

Near Tee Harbor we chanced upon several orcas (=killer whales), splashing about and moving along the shores. There were several orcas, including one quite small one, mostly foraging independently, not in a close bunch. I guessed that these were likely to be the fish-eating ‘resident’ sort of orcas, probably after spring king salmon. Orcas had recently been seen near downtown in Gastineau Channel too, and we wondered what had lured them there.

We were treated to the delightful presence of several Dall’s porpoises, rushing hither and thither, sometimes riding our bow waves. A picturesque little flight of swans headed north, against a backdrop of the Chilkats. And I have not even mentioned the pigeon guillemots, marbled murrelets, loons, Arctic terns, scoters of two species, and clusters of Bonaparte’s gulls dipping down to the water surface to snatch some tiny prey.

Altogether, very satisfactory wildlife viewing, and fine days on the water!

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