Alcatraz Island has once again become a significant marine bird habitat. Last year, rangers spotted nearly 900 nesting pairs on the island, one of the highest counts since the National Park Service took over the 22-acre island in San Francisco Bay in 1972.
With this year's nesting season well under way, Daphne Hatch, a wildlife specialist with the park service, said she was hopeful that the 1996 count will be even greater.
Historically, Alcatraz was an important avian environment. Indians collected eggs there, and 18th-century Spaniards named it for the flocks of sea birds they found perched on its rocky slopes.
With the arrival of thousands of fortune seekers during the Gold Rush, however, the birds suffered. A thriving colony of Western gulls was decimated by egg collectors who supplied hungry '49ers.
Later, nesting areas were destroyed as construction successively transformed the island into a fort, a military prison and, finally, a maximum-security federal penitentiary.
The birds left.
Since the prison closed 33 years ago, the National Park Service has succeeded in luring a half-dozen species of marine birds back to breed in the vegetation, rubble piles and open spaces around the crumbling buildings.
Other species are regular visitors. Recent sightings include cormorants, loons, brown pelicans and pigeon guillemots. The western gull population is on the increase, and significant numbers of black-crowned night herons, small nocturnal hunters, breed on Alcatraz from mid-February to early summer.
In 1995, the first pair of black oyster catchers -- jet-black birds with bright red legs and bills -- nested on the island.
Pub Date: 4/07/96