The Butterfield family has donated Pearl Island to the Bermuda Audubon Society (BAS) for endangered tern nests.

BAS has enjoyed a rent-free lease on Pearl Island since 1969, however, trustees of the Dudley Butterfield Estate donated the one-quarter acre outcrop as a permanent nesting site for rare birds.

"Common terns are now Bermuda's rarest sea-bird," BAS president Andrew Dobson said. "This species requires rocky coastal sites, free from cats, rats and human disturbance."

Mr. Dobson said Pearl Island was an important gift site because it had been a successful breeding site for many years.

"Hurricane Fabian in 2003 seriously affected the population of Bermuda's terns," he said. "This fine gesture by members of the Butterfield family provides a guaranteed sanctuary for the common tern."

The island also contains a channel marker and BAS said it was grateful to the Department of Marine and Ports for its careful use of the island.