Florida's butterflies threatened by changing ecosystem

[Bob Parcelles,Jr.]

Florida's butterflies threatened by changing ecosystem
By DINAH VOYLES PULVER (dinah.pulver at news-jrnl.com)
Environment Writer
A shimmery swallowtail swoops softly across a street. Suddenly, splat!
Windshields and grills win every time. 

Millions of butterflies die every week on roads in Florida, but cars
and trucks are only part of the dangers they face. Mosquito spraying,
roadside mowing and habitat loss also wreak havoc on Florida's
butterfly populations. 

Monarch butterfly 

At least 10 percent of the state's 160 resident species of lepidoptera
are in trouble, said Marc Minno, an insect ecologist. The biggest
threat to those butterflies is loss of or changes to habitat. 

"We've reached the point where there are more than 15 million people in
Florida," he said. "There probably isn't any natural community that is
the same as it was 300 years ago." 

To Minno, it seems almost miraculous that few species have been lost,
but now the situation has reached a critical level, he said. "We will
begin to lose things if we don't do something to save them." 

Across the state, conservationists are battling to save the fragile
flutterers. 

A full-scale campaign is under way in South Florida to get the Miami
blue butterfly on the endangered list. Only one species -- the Schaus'
Swallowtail -- is now on the list. 

In Gainesville, a doctoral student at the University of Florida toils
to prove one species of hairstreak butterfly is threatened so its
habitat can be preserved. 

And in Port Orange, Patty Bruda regularly crusades to recruit gardeners
to be more butterfly friendly in their yards. A master gardener with
the Volusia County Cooperative Extension Service, Bruda lectures local
garden clubs on how to attract butterflies and provide host plants for
their young. 

Most people are anxious to learn, Bruda said, and that's good because
backyard gardens could one day be the butterflies' last stand. "These
creatures are going to become dependent on us to know their needs and
to provide for them." 

Bruda gets excited when she sees one of the threatened species in her
yard. 

In Volusia and Flagler counties, Minno said, at least three species, if
not more, seem to be vanishing -- the tiger swallowtail, the arogos
skipper and the dusted skipper. 

J. Akers Pence of Gainesville is witnessing firsthand the havoc habitat
loss can wreak on a single species. In his doctoral dissertation for
the University of Florida, Pence is studying the Sweadner's Juniper
Hairstreak. 

The butterfly may be found in as many as 20 counties, but he thinks its
numbers are dwindling rapidly. 

One population he studies is in Flagler County in a grove of cedars in
Bunnell. A few weeks ago Pence arrived to find someone had knocked out
trees in the cedar grove to build a new entrance for an adjacent
business. 

"Four of the 18 trees were part of a study site I've been monitoring
there for three years," he said. 

On the West Florida coast in Yankeetown, a cedar grove behind the local
Lions Club is in all the butterfly guidebooks as a place to go to look
for the Juniper Hairstreak butterfly. On a recent visit Pence was
dismayed to find a "for sale" sign on the grove. 

Development and the urban sprawl that leads to new roads and
subdivisions in pristine areas are the worst threat to butterflies,
Pence said. The predominant plant in new housing communities, landscape
grass, does little to promote species diversity. 

Pence quotes a recent study by Duane and Katherine McKenna at Harvard
University. The study concluded 20 million butterflies die on Illinois
roads each week between August and October. Of those, Pence said,
500,000 are on interstates, 5 million on other highways and 15 million
on two-lane roads. He said the numbers may be much higher in Florida. 

"How many roads have we seen in Florida that start out as little
two-lane dirt roads and then eventually get paved and widened and
widened again?" he said. 

Large land acquisitions that preserve ecosystems help, but buying the
land and making parks isn't enough, Minno said. "You have to manage
that park and that has its own problems." 

For example, many natural communities depend on fire and if the shrub
grows up, you lose the butterflies, he said. That's one reason
grassland species are in trouble. 

But after the shrub has grown too high, the fuel-rich wildfires or
prescribed burns can get too hot or too many acres are burned at once
and really rare species can be lost, Minno said. 

For example, one colony of rare arogos skippers lived on either side of
a dirt road in the Ocala National Forest, moving from one side to the
other each time there was a prescribed fire. Then one year in the
mid-1990s both sides of the road were burned at once and the
butterflies have never been seen again, Minno said. 

One threat that long has worried butterfly experts -- mosquito control
-- is more controversial than ever as officials expand their efforts to
control the spread of the mosquito-borne West Nile virus. 

Pence calls mosquito control spraying silly. "It kills all kinds of
nontarget things, like dragonflies that would have eaten tons of
mosquitoes in their lifetimes," he said. "And aerial spraying is the
worst." 

Jonas Stewart, director of the East Volusia Mosquito Control district,
says the industry's studies show the spraying is fairly safe. 

It isn't likely that spray trucks harm butterflies for two reasons,
Stewart said. Spray trucks fog at night because mosquitoes are night
fliers, he said. Butterflies are day fliers so they hide in the
vegetation at night, he said. And even if a butterfly is sprayed, the
spray -- from trucks or from airplanes -- is very fine, he said,
targeted specifically at tiny mosquito-sized insects, and shouldn't
harm larger bugs. 

Yet of all the impacts humans have on the environment, one irritates
Pence more than others because he said it's so thoughtless --
electronic bug zappers. 

"All those sparkles and pops are sucking harmless or beneficial
creatures out of the air," he said. "Some of them would be pollinators,
some would be a part of the food chain." 

Learn how to attract butterflies to your garden in Tuesday's
News-Journal. 

Did you know? 

-- The reason butterflies flicker and flutter and rarely sit still is
to avoid predators. 

-- If a female butterfly lives long enough to lay 100 eggs she's a
great success if just two of those eggs actually become butterflies. 

-- Butterflies don't develop brilliant color until they're about the
size of a small human finger so they can hide from predators. 

-- Electric bug zappers may kill up to 350 billion beneficial bugs
every year, with fewer than 1 percent of the dead bugs being biting
flies or gnats, according to a University of Delaware study. 

-- For more information on butterflies, visit: The North American
Butterfly Association at www.naba.org or The Northern Prairie Wildlife
Research Center's list of butterflies in Florida at
www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm. 


--------------------------------------------------------------------------------
© 2002 News-Journal Corporation. ® www.news-journalonline.com. 

=====
Bob Parcelles, Jr 
Pinellas Park, FL 
Ecologist/Ethologist, RJP Associates
CEO, PROactive Ecology Solutions Group (PESG)
Institute of Ecological and Environmental Studies (IEES)
http://www.Ecology-Today.eboard.com
http://groups.yahoo.com/group/naturepotpourri

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