Summer seems like an odd time for birds to migrate north. Most are wrapping up breeding and preparing for the southward trek. Yet every summer, brown pelicans make the pilgrimage to the Pacific Northwest from breeding islands along the coast of Southern California and Mexico.
Apparently, the cuisine here is not to be missed.
It has to do with ocean upwelling off our coast that brings nutrient-rich waters from deep in the ocean to the surface. Mix these waters with a little sunlight, and you have a culinary bonanza. The same conditions produce squid, krill and other bounty.
The abundance attracts many species besides pelicans, including several different shearwaters from as far as Chile, New Zealand and Australia, not to mention whales. As whale numbers continue to rebound from overhunting in the 19th and early 20th centuries, both blue and humpback whales are becoming more common along our coast.
Only eight species of pelicans occur around the world. Six species are white, like our American white pelican and live on inland lakes sedately netting fish from the water. The remaining two species are gray-brown in color and include our brown pelican along the coast.
Unlike their pale relatives, they feed in a more spectacular fashion. Flying over the coastal waters, they plunge into the ocean, mouths agape, water splashing everywhere. On occasion, I have mistaken the results of these collisions as whale spouts.
As a pelican dives into the water, the pouch balloons full of water, stopping the dive almost instantly. It looks painful, but they don't seem to mind. Bobbing to the surface, they squeeze out the water and swallow the fish, if any.
I don't think of brown pelicans as messy feeders, but apparently they are. Each summer as brown pelicans come north along the coast, their faithful shadows — Heermann's gulls — tag along. Many gulls are similar in appearance and a challenge to identify. The Heermann's gull, however, is distinctive. It has a white head like many, but the bill of the adult is blood red and the body is a slate gray.
Heermann's gulls rely on pelicans for much of their food. As a pelican forages, at least one gull is usually in close attendance. When the pelican takes off from the water, the gull immediately follows. As soon as the pelican dives, the gull rushes in to pick up any stunned fish or fish the pelican drops. The gull will even pluck a fish from the mouth of the pelican if it gets the chance.
Watching this show is quite entertaining, and I can't help but wonder how the pelicans feel about their close and constant companions. It would be annoying, much like the occasional fly that just won't go away.
As colder fall weather sets in, both will retreat to warmer climates, even though fish won't be quite as abundant. By Christmas they are usually gone. One winter, some pelicans lingered just a bit too long, and freezing weather caused frostbite. A number died.
They won't be absent for long. Nonbreeders will reappear off our shores by May, with the rest following in July. I suspect that if our winters were just a bit warmer and less windy, they might even breed on the islands off our coast.
Stewart Janes is a biology professor at Southern Oregon University. He can be reached at email@example.com.