BY JOSH GORE Free Press Staff
The roseate spoonbill, a wading bird long enjoyed by birdwatchers, recreational boaters and anglers, appears to be gradually leaving Florida Bay for less salty nesting grounds, according to Audubon researchers. The spoonbill nests during the dry winter and spring months. And because it is especially dependent upon the natural wet summer/dry winter seasonal cycle of the Everglades, the bird has been studied as a key indicator species for the overall health of Florida Bay.
Spoonbills, as well as the other wading birds of Florida Bay and the Everglades, rely on the rainy summer season to fill up freshwater marshes so prey fish will have plenty of space in which to breed. During the dry season, those fish are forced into the ever-dwindling wet areas, creating a smorgasbord for spoonbills while they have nesting chicks to feed. Researchers this past nesting season counted 125 roseate spoonbill nests in Florida Bay and 265 in the inland Everglades. Audubon researchers first began tracking inland nesting four years ago and preliminary data suggests their numbers are rising. A decade ago, the bay contained 546 roseate spoonbill nests, and those numbers have shown an overall decline since 2001. Audubon researchers believe the decline of nesting in the bay can be explained by the advance of more saltwater through the bay and into the Everglades.
“Whether or not you believe in climate change, you cannot argue with rising sea levels,” said Audubon biologist Peter Frezza. Counting the nests is a process that takes months for researchers, says Heather Rafferty, a Audubon biologist. “We try to get in and out as fast as possible, usually between 15 and 30 minutes,” she said. “The goal is to minimize the disturbance.” The counting took place from November into May. This year’s numbers are quite similar to last year’s figures, which researchers say indicate that the previous season’s data wasn’t a fluke. “We are continuing to see a trend in these low nesting numbers,” Frezza said. “At best, we are surmising the birds are transitioning.” Frezza said
Audubon’s Tavernier Science Center has begun analyzing water levels from the Gulf of Mexico as well as the ocean.“You can blame the gulf and the Atlantic Ocean,” he said. “There is a correlation with high water in Florida Bay.