Food source buried in the sand

Posted: Sunday, May 21, 2000

Tourists seldom notice the most important animals in Glacier Bay.

The whales, sea birds and salmon would go hungry, if not for schools of small, silvery forage fish. The National Park Service's mapping project discovered that the forage fish -- a key link in the food chain of Glacier Bay -- spawn on coarse sand beaches with little silt.

The park managers now consider all 200 coarse-sand, low-silt beaches in Glacier Bay to be potential spawning grounds, and high on the list of areas to protect, said coastal ecologist Lewis Sharman.

``We anticipate that some of the outcomes of a project like this is that you will make these types of discoveries,'' Sharman said.

But if Park Service biologists weren't walking and inspecting the beaches, the spawning grounds would have been missed.

``You could boat right by it and not even notice it's there,'' Sharman said.

Stepping out of the boat onto the sandy beach by Rush Point in July 1997, CoastWalker Bill Eichenlaub noticed something looked different. He reached down to scoop a handful of the miscolored sand.

``It looked like someone mixed couscous with sand,'' Eichenlaub said. ``My hand was just full. I had hundreds and hundreds of eggs in it, mixed with the sand.''

Eichenlaub later calculated there were at least 1.8 billion eggs in those 300 feet of beach. Eichenlaub found two other beaches covered with eggs, both coarse sand beaches with minimal amounts of silt.

The eggs belong to some kind of forage fish, probably herring or capelin, though fish biologists for the National Park Service aren't sure yet.

The forage fish are a key link in the food chain of Glacier Bay. The little fish, barely six inches long, eat zooplankton, which eat phytoplankton. And the forage fish are eaten by everybody -- salmon, halibut, sea birds, even mink, wolves and bear.

``Everything eats them. Seals eat them. Whales eat them. Sea lions eat them,'' Sharman said. ``It's kind of the bread and butter.''

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