Tuesday, Sep 02, 2014
Local News

Sparrow Working Group out to save endangered bird in Avon Park


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– Currently, Highlands County and possibly the world are on track to becoming more featherless.

But an effort is on to save a critically-endangered bird subspecies found only in three refuges in Florida, one in Avon Park, even though it’s an uphill battle.

As of this summer, the number of Florida grasshopper sparrows -- a grassland bird found only in the dry prairies of south-central Florida -- may be as low as 10 on the Avon Park Air Force Range.

That is one of three remaining refuges around the Kissimmee River Basin, which includes Kissimmee Prairie Preserve State Park in Okeechobee and Three Lakes Wildlife Management Area in Osceola County.

The sparrow lives primarily in grasslands in Florida’s interior south of Orlando and has been listed as endangered for nearly 30 years.

To help possibly stop the bird’s slide into ecological oblivion, the Florida Grasshopper Sparrow Working Group was formed by land managers and biologists in 2002 to help formulate a recovery plan to establish 10 populations of at least 50 birds each.

An average of 15 to 20 members of the group, from north and central Florida and Maryland, have been actively monitoring the plight of the bird at each site.

Two members, Gregory Schrott, an Archbold Biological Station scientist and a past chairman of the working group, and Mark Fredlake, an endangered species biologist at the Air Force Range, make monthly, early-morning forays onto sparrow habitat on the 106,000-acre bombing range.

From his office on the bombing range Monday, Schrott said the sparrow is critically endangered as a result of habitat loss, restricted range and population decline.

In addition, the bird’s reclusive nature makes it hard for biologists and land managers to identify what’s thinning its population.

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Once a month from late March to early June, group members who meet in Archbold, Vero Beach and Florida Fish and Wildlife Conservation Commission offices venture out from before sunrise to about two hours after visiting designated “point spots” on the bombing range -- areas found on Global Positioning Satellite that have had sparrow sightings and evidence.

There, they stand and listen for the sparrow’s grasshopper-sounding call and do a “point-count census.”

Data is recorded, and with Conservation Commission permission, audio recordings of sparrows are played in the prairie in order to illicit responses from other grasshopper sparrows in the area.

As the years go on, those opportunities are becoming more infrequent, said Schrott, who has been with the group since 2007.

He said the count went from an estimated few hundred birds to less than 20 in four or five years through 2011, with the biggest drop from 1999 to 2002.

Now, there are probably fewer than 10 in Avon Park.

“There are not many birds left on the property. It can be a frustrating thing. Morning after morning coming back and not having anything to report,” he said. “But knowing where they’re not is as important as knowing where they are so we know what are the most important spots with the propensity for the sparrow.”

Fredlake, who is associated with the sparrow group since 2008, said the birds are short-lived, averaging two- to three-year lifespans; only a few young are reaching adulthood.

He said the sparrow’s rapid decline, particularly in Avon Park, is a “mystery” and without nesting success, finding subjects to study is almost impossible.

“We’ve had a lot of time to solve this, but we’re scrambling for answers. We don’t have enough birds to establish a rigorous hypothesis,” he said.

In 2012, the Cornell Lab of Ornithology stated the sparrow’s extinction would likely be the nation’s first loss of a bird since the late 1980s.

During those 10 years, the native dusky seaside sparrow disappeared. Schrott said anytime a bird species is lost forever, it’s a symptom of profound ecological problems associated with Florida’s shrinking prairie environments.

The threat of losing another bird unique to Florida alarms scientists, who also worry the grasshopper sparrow’s rapid decline might be a sign of profound problems with the state’s dwindling prairie environment.

Statewide, there may be fewer than 200 Florida grasshopper sparrows alive, including fewer than 100 in the Three Lakes area.

“If you go by the book, you come up with what the bird needs. You provide and restore that prairie area and the bird should respond and grow. But that’s not happening; we’re not getting a response,” he said.

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Plans are being hatched to stop the threatened extinction. In April 2013, federal and state wildlife officials announced plans to launch a captive breeding program for the sparrow.

That involves collecting eggs from any nests that can be located and hatching them at the Rare Species Conservatory Foundation in Loxahatchee where any hatchlings the eggs produce could be kept in captivity with hope they will mate and breed, what Schrott calls “a last resort.”

Fredlake said not only is saving the sparrow critical to Florida’s ecosystem, it’s also mandated under the Endangered Species Act of 1973, passed to protect and recover imperiled species and the ecosystems.

“They’re important to maintain the genetic diversity. You lose one bird, it may not seem important. But over time, it shows a trend that will affect all of at some point. It may not be important at the time, but may be invaluable for medical and biomedical applications down the road,” said Fredlake.

The small bird -- a subspecies of the grasshopper sparrows, thrives best in expanses of “dry prairie.” Florida had more than 1.2 million acres of treeless terrain but 90 percent of it was turned into cattle pasture by the end of the 20th century.

pcatala@highlandstoday.com

(863) 386-5855

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