The Audubon Naturalist Society declared a rare-bird alert last week when two 13-inch European cousins of the crow turned up at the federal penitentiary here, munching bread crumbs provided by the inmates.

The appearance of the nesting jackdaws, as common as red noses in England but almost unheard of in the States, sent scores of Washington- and Philadelphia-area bird buffs scurrying off to augment their North American life lists and still get home for supper.

"We'll just run up in the morning, nail the bird and go fishing in the afternoon," said veteran birder Jay Sheppard, a U.S. Fish and Wildlife Service biologist from Laurel, Md.

Sheppard lured along fellow scientist and fly fisher Gail Mackiernan. As they drove up I-83 on the first leg of the 300-mile round-trip jaunt, she mused how nice it would be if the Lewisburg jackdaws produced young and the species went on to become common.

"Then you could say you saw 'em first," she said. "I had some friends who saw the first cattle egrets when they arrived from South America back in the '50s. Now cattle egrets are everywhere."

Sheppard seemed more interested in tacking a new bird onto his impressive life list. It would be his 636th, he said, and at that level additions come hard. He recorded No. 600 back in 1968.

Sheppard is at the point of looking mostly for quirks -- nonmigrating birds from afar that ride across the sea on ships, arctic creatures that get lost during their lengthy migrations or birds forced far out of normal patterns by climate or food disasters.

When such a bird crops up, the news travels fast. Sheppard said the day he went to see Ross's Gull in Newburyport, Mass., a few years ago, he saw 1,000 birders, too.

The Lewisburg jackdaws were appealing because they were close to home and yet extremely rare in North America. Sheppard needed a British bird book just to get a description.

He guessed the birds were from a group that evidently flew across the Atlantic to Labrador in the fall of 1983, when jackdaws massed in unprecedented numbers in western England, presumably because the grain season inland was poor.

Several jackdaws were sighted the following summer in Quebec, where farmers reportedly shot them as potential nuisances.

Then the news of the Lewisburg pair popped up last week on the Washington Naturalist Society's taped telephone message, which provided rough directions to the viewing spot.

Sheppard parked at the recommended dip in a country road and set off across a bug-infested corn field toward a tower in the middle of the prison yard.

But a chain-link and barbed-wire fence encircled the prison a half-mile from the tower. A trampled spot in the grass indicated where previous birders had camped outside the fence. It was less than an ideal vantage point. Worse, three birders from Penn State University were trundling off after watching all morning and seeing nary a jackdaw feather.

Sheppard mounted his 40-power scope on a tripod and commenced his prison vigil.

Bobolinks flitted around in the still, summery air. Cock and hen pheasants cackled across the fields. A killdeer buzzed close by, peeping. Boattail grackles, starlings, crows and redwing blackbirds flapped merrily about, looking enough like jackdaws to keep the visitors alert. Pigeons flew in and out of the tower roosts.

By afternoon, the wait grew wearying. The birders set off for Penns Creek, where the bass fishing was about as good as the bird-watching.

At evening, reasoned Sheppard, the jailbird jackdaws should come home to roost. At 6, he resumed peering into the compound.

The prison slow-pitch softball game was under way, pitting the blue-shirted Lewisburg Angels against the yellow-shirted Lewisburg Royals.

It is not easy to watch a softball game from that distance, but a 40-power scope helps, as does a sense that nothing else is going to happen. After five innings, it was Royals 21, Angels 12, principally a result of nine-run scoring sprees in the Royals' first two at bats.

With the birders cheering them on, the Angels rallied, drawing within 21-16 in the sixth, but the Royals scored twice in the top of the seventh inning and won, 23-19.

By then, the sun was dipping behind the tower and there were 150 miles yet to travel.

So it goes sometimes on a world-class birding trip: No birds, no bass, lousy seats and no one even gets home for supper.