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Rules let bird population take wing

While some water scooter users and water-skiers aren't too happy with boating restrictions on Alligator Lake, the bird population is loving it.

A recent survey by Tampa Bay Sanctuaries, a chapter of the National Audubon Society, found that nesting pairs of birds have doubled since the city imposed a vehicle exclusion zone around two islands in the lake two years ago.

"It's a very little lake," said Anne Schnapf, a wildlife biologist with Tampa Bay Sanctuary. "It doesn't take a lot of motorboats to make it even tinier."

Schnapf, who led a team of volunteers to conduct the study, said nearly 800 pairs of various types of herons and egrets nest in the willows and groundsel trees that cover the islands. Other birds calling the island home include least bitterns, anhingas and limpkins.

Several of the birds belong to "species of special concern," which means the Florida Game and Fresh Water Fish Commission thinks they are at risk of becoming endangered.

"Since the 1940s, the heron and egret populations have decreased over 60 percent in Florida," Schnapf said. "If we protect these small sites, we can have the species with us forever. If not, they just won't be around anymore."

The nest count is an estimate, Schnapf said, but it should be a fairly accurate one. Using the "flight line census technique," she counts the birds as they leave in their morning quest for food. Knowing a mate is left at the nest to guard it from fish crows and other predators, the total count is doubled.

When Schnapf surveys the lake, she stays on special lookout for the reddish egret, a bird she has seen each of the past two years.

"This is the only case we know of where a reddish egret has nested in freshwater," she said.

The reddish egret feeds in saltwater and usually nests there too. Schnapf said Alligator Lake's proximity to Tampa Bay is probably the reason.

Nature provides another reason why the island habitats of Alligator Lake's birds are thriving. Raccoons, which can disrupt a bird habitat, would love to live among the nesting bird population. But any raccoon trying to swim to the islands would probably be eaten by an alligator on the way.

Schnapf said the buffer around the island has had a dramatic effect on the bird population.

"We just need to back off and give them a place to breed and nest," she said.