Fort Myers, Florida (News-Press) -- One of Florida's most endangered birds is making a comeback in the mostexotic of ways, feeding off an invasive critter that feeds mostly off aninvasive plant.
Snail kite numbers havejumped statewide from 650 in 2007 to about 1,200 today. While that'sonly a fraction of the 3,400 birds found here in 1999, the rebound ratehas shocked the science world. The next breeding season starts inJanuary, and scientists aren't sure what to expect.
"Wehave a bird that was in dire straits that is now taking advantage ofthis proliferation of an exotic species that exploded," said WileyKitchens, a biologist and bird expert who conducts research for the U.S.Geological Survey and the University of Florida.
"Wewere looking at almost an eminent extinction," Wiley continued. "That'swhere we were about four years ago - really, really concerned."
Thesubspecies found here exists only in South Florida and Cuba, althoughKitchens and others believe the two populations do not interbreed. Snailkites in Florida are not only endangered, but the birds are also one ofthree indicator species used to gauge Everglades recovery andrestoration. The species may lose that status, however, because theadaptation to the invasive snail means the snail kite may no longer bereflective of South Florida's ecology.
Theinvasive island apple snail thrives on hydrilla, an invasive plantthat's capable of choking small freshwater systems and retention ponds.But as hydrilla and the invasive island apple snail has thrived andexpanded their range, so has the snail kite. Hydrilla is an aquaticplant that was introduced to Florida in the 1950s through the aquariumindustry. Twenty years later the plant, known for killing off otherwater plants and even altering water flow and possibly killing fish, hadspread throughout the state and is now found as far north asConnecticut and west to California.
Island apple snails in Florida exploded in population after the active 2005 hurricane season, Kitchens said.
"Thenumber of birds began to increase, and it turns out that snail ispopping up all over Florida," Kitchens said. "Wherever we see abreakout, the birds flock in. It's a monumental turn-aroundecologically. For the first time in a decade, we've seen the nestingback up to the levels when the population was around 3,400 birds."
Zach Welch, snail kite coordinator for the Florida Fish and WildlifeConservation Commission, said hydrilla and the island apple snails arefound mostly in altered systems such as Harns Marsh, a 578-acre man-madefilter system designed to retain and clean storm-water runoff.
"Theydo well in altered areas," Welch said of the invasive apple snail,which is much larger than native species. "But it's not good news forour snails. We haven't fixed the problems."
Snailkites have evolved in Florida along with native snails, which are indecline due to drainage projects and polluted water sources.
Whilesome invasive species can displace, even eat native animals, the islandapple snail, which is particularly hardy, hasn't done a lot of damage,yet.
"So far wedon't see any negative impacts ... It's good because if we did have toeliminate them, we'd have no idea how to do it," Welch said.
Kitchens said scientists aren't sure how the invasive snail and the endangered kite will fare.
"There'sa lot of uncertainty there," Kitchens said of the future of the snailkite and its relatively new food source. "And that uncertainty incompounded because the last thing ecologists want to promote is theexpansion of an exotic species."