Classes are divided into two sections; one for making a ruddy duck, which Mrs. Somoroff said has a "pert personality and good coloring."

Sunday at 11 a.m., a search for waterfowl like mergansers, ruddy ducks and buffleheads, led by the Urban Park Rangers.

The Department of the Environment in Britain is financing a three-year, $100,000 study on how to contain the ruddy duck.

The ruddy duck, which appears in large numbers in its proper native environment, does not.

"The main problem is the continued expansion of the ruddy duck," Dr. Owen said.

A solitary goldeneye was lingering on, as per last year, and the ruddy duck has dropped to six from the record 52 we counted in March.

"Some ruddies, too," said Kirk Weber, who was hiking with him, pointing out some ruddy ducks paddling contentedly in the same broad swath of shallow water.

Mr. Torino asked a woman who was peering through her binoculars at some ruddy ducks.

"The ruddy ducks are here," he said, surveying the flocks.

And what about the ruddy duck?