Late summer brings great excitement to Southeast Alaska when spawning salmon return to their natal streams. If you take time to visit one of these spawning areas, there's a great show to watch as gulls and other birds congregate in great numbers to feed on the dead and dying fish.
One year in August, Bob Armstrong sat for two hours in the parking area near the DIPAC hatchery at Sheep Creek, where hordes of chum and some pink salmon crowded the stream, excavating nests, depositing eggs and covering the eggs with gravel.
Here's some of what he saw:
It was low tide and I could see the whole intertidal portion of the stream, the tidal flats surrounding it and a sandy gravely berm the birds used for loafing and sleeping.
I watched the birds from the comfort of my van, using 10-by-40 binoculars and a 25-power spotting scope mounted on the window. A vehicle like that makes a good blind and will keep the birds from flushing, as they do whenever people approach on foot.
I estimated there were about 3,000 gulls in the area. The largest of them - glaucous-winged gulls - seemed to feed mostly by tearing into the bodies of dead salmon. On several occasions, however, I saw them punch hard with their beaks at the bellies of female chum salmon still alive in the stream. Then they'd quickly move toward the back of the fish to gobble up the eggs extruded from the vent.
I saw one enterprising fellow pull a live female pink salmon from the stream and systematically pinch-bite its belly, obviously having figured out that this would cause it to extrude the eggs he was after.
I enjoyed watching interactions among these large gulls. When one intruded too closely while another was feeding, the feeding gull would erect its neck feathers, move its head up and down and squawk loudly. If a gull was really pushed, it would charge with its wings outstretched and attempt to nip the intruder. They were quite aggressive toward each other.
The medium-sized mew gulls foraged a little differently. A few pecked at the flesh of spawned-out salmon, but most of them darted about in the shallow water of the stream picking up loose salmon eggs.
At least one of them used a technique I've seen other mew gulls use to expose small crustaceans in muddy intertidal areas: It stood in the water rapidly moving its feet up and down. That apparently created an upwelling that brought more loose eggs to the surface and within its reach.
The mew gulls seemed to be bickering with each other constantly. They'd run at each other with their heads down, sometimes with their wings outstretched or their heads thrown back. Occasionally they'd nip at other mew gulls to chase them away from where they were feeding.
There were Bonaparte's gulls there, too. These small gulls fed by hovering just above the surface of the stream and diving tern-like after the drifting eggs. This method of feeding seemed to require a great deal of concentration and the Bonapartes paid hardly any attention to each other.
The three species of gulls did not seem to interact with each other and when they weren't feeding they all loafed and slept together. They even bathed together as the tide came in and created a deeper, calmer stretch of water.
So many fish were scattered around the area, many of the birds I watched wandered about sampling one fish after another. I wondered if, like bears, they select just the tastiest, most nutritious morsels when they have so much food to choose from.
You can see different versions of this performance on many Southeast Alaska streams. Other species of gulls, as well as ravens, crows, eagles and bears always turn out for the late summer feast. It's an age-old cycle in which nutrients from the spawning salmon make their way throughout the food chain in Southeast's streams, tidal flats and forests.
The Southeast Wild column is written by members of the Juneau Audubon Society. Monthly meetings of the society resume the second Thursday in September. Contact members at email@example.com.