A snail kite takes flight in Lehigh Acres, Florida. The endangered bird is making a comeback. (Andrew West/The News-Press)
Fort Myers, Florida (News-Press) -- One of Florida's most endangered birds is making a comeback in the most
exotic of ways, feeding off an invasive critter that feeds mostly off an
Snail kite numbers have
jumped statewide from 650 in 2007 to about 1,200 today. While that's
only a fraction of the 3,400 birds found here in 1999, the rebound rate
has shocked the science world. The next breeding season starts in
January, and scientists aren't sure what to expect.
have a bird that was in dire straits that is now taking advantage of
this proliferation of an exotic species that exploded," said Wiley
Kitchens, a biologist and bird expert who conducts research for the U.S.
Geological Survey and the University of Florida.
were looking at almost an eminent extinction," Wiley continued. "That's
where we were about four years ago - really, really concerned."
subspecies found here exists only in South Florida and Cuba, although
Kitchens and others believe the two populations do not interbreed. Snail
kites in Florida are not only endangered, but the birds are also one of
three indicator species used to gauge Everglades recovery and
restoration. The species may lose that status, however, because the
adaptation to the invasive snail means the snail kite may no longer be
reflective of South Florida's ecology.
invasive island apple snail thrives on hydrilla, an invasive plant
that's capable of choking small freshwater systems and retention ponds.
But as hydrilla and the invasive island apple snail has thrived and
expanded their range, so has the snail kite. Hydrilla is an aquatic
plant that was introduced to Florida in the 1950s through the aquarium
industry. Twenty years later the plant, known for killing off other
water plants and even altering water flow and possibly killing fish, had
spread throughout the state and is now found as far north as
Connecticut and west to California.
Island apple snails in Florida exploded in population after the active 2005 hurricane season, Kitchens said.
number of birds began to increase, and it turns out that snail is
popping up all over Florida," Kitchens said. "Wherever we see a
breakout, the birds flock in. It's a monumental turn-around
ecologically. For the first time in a decade, we've seen the nesting
back up to the levels when the population was around 3,400 birds."
Zach Welch, snail kite coordinator for the Florida Fish and Wildlife
Conservation Commission, said hydrilla and the island apple snails are
found mostly in altered systems such as Harns Marsh, a 578-acre man-made
filter system designed to retain and clean storm-water runoff.
do well in altered areas," Welch said of the invasive apple snail,
which is much larger than native species. "But it's not good news for
our snails. We haven't fixed the problems."
kites have evolved in Florida along with native snails, which are in
decline due to drainage projects and polluted water sources.
some invasive species can displace, even eat native animals, the island
apple snail, which is particularly hardy, hasn't done a lot of damage,
"So far we
don't see any negative impacts ... It's good because if we did have to
eliminate 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.
a lot of uncertainty there," Kitchens said of the future of the snail
kite and its relatively new food source. "And that uncertainty in
compounded because the last thing ecologists want to promote is the
expansion of an exotic species."