Wood storks have come home to roost in southern Florida, but but naturalists are worried that the endangered birds won't have a chance to rear their young before the rainy season. Summer deluges at the storks' two major ancestral breeding grounds would drench nestlings and disperse the fish the birds rely on for food, they explained. Last week, 620 pairs of wood storks were nesting at Corkscrew Swamp Sanctuary, a National Audubon Society refuge about 20 miles north of Naples that was once the primary stork-nesting area in North America. Another 75 pairs have taken up residence at Everglades National Park's Cuthbert Island. The two sites were believed to have been all but abandoned by North America's sole species of stork, a giant white bird with an iron-black head. ``We are ecstatic to be able to report these numbers,'' said Paul Hinchcliff, chief naturalist at Corkscrew. ``Whether or not there's enough time before the start of the rainy season to fledge enough young remains to be seen.'' Almost all previous attempts to nest so late in the year have ended disastrously, said John Ogden, who heads a wood stork study team at Everglades National Park. If they are unable to feed offspring, parent birds will abandon the colony, leaving hundreds of crying young birds to starve. Wood storks have not produced offspring in significant numbers at Corkscrew since 1984-85, when 353 pairs of birds successfully raised 530 young. Fifty years ago, it was common to see 6,000 to 8,000 pairs of storks nesting in the gray-boughed cypress trees. Since the early 1960s, however, storks have been spurning Corkscrew in favor of central and northern Florida and other Southern states. Between 1960 and 1980, the wood stork nesting population at Corkscrew dropped by 75 percent. The renewed Corkscrew colony represents almost 30 percent of the total U.S. stork population, estimated at 4,000. Historically, storks came to Corkscrew by the tens of thousands to nest in early winter, leaving plenty of time to rear offspring before the onset of rain. But human activity disrupted the annual cycle of high-water summers and low-water winters in Florida's wetlands. Much of the area that provided shallow feeding waters for wood storks during the early winter has been drained for farming or sudivisions. The birds have been forced to wait until late winter or spring for the deeper waters of the interior Everglades to drop low enough for them to efficiently feed. As result, nesting is delayed, and this year's young won't be ready to leave their nests until about mid-July, Ogden said.
