Once known for its wood stork nesting, Corkscrew Swamp no longer a breeding stronghold

Wood storks filled the skies and cypress tree canopies of Corkscrew Swamp Sanctuary for millennia, breeding and feeding their young in one of the largest bald cypress forests on the planet.

"A 1914 account from May of that year says there were over 100,000 wood storks ― and herons, egrets, (roseate) spoonbills and ibis as well ― but 100,000 wood storks, and it's a point in time where you can see the carrying capacity of Southwest Florida," said former sanctuary manager Jason Lauritsen.

But what was once the largest stork nesting site in North America has crumbled in recent years.

With much of the surrounding areas having been developed in recent decades, there simply may not be enough food on the landscape to support the birds and their offspring anymore.

"It takes 443 pounds of fish to feed one pair of storks and fledging young," Lauritsen said. "You look at Corkscrew now and the thing seemingly on the chopping block is the wood stork nesting."

Corkscrew Swamp Sanctuary is an ecological gem outside the Naples area, and managers and volunteers there are celebrating 2024 as it marks the sanctuary's 70th year.

The Sanctuary is managed by Audubon, and more than 100,000 people traverse its famous cypress slough boardwalk each year.

And while North America's only stork can still be found in the swamp, they're not nesting there on a regular basis.

Short-season wetlands are largely gone

Wood storks are massive wading birds with huge bills that need shallow wetland conditions in order to feed and grow their young.

With cotton-white feathers and dark grey bills and legs, wood storks can often be seen soaring high in the sky on warm spring days.

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Corkscrew Swamp Sanctuary is in the middle of a cluster of preserves in south Florida, and it lends connectivity between places like the 60,000-acre Corkscrew Regional Ecosystem Watershed, or CREW to lands as far away as Everglades National Park.

But much of the lands surrounding the sanctuary have been converted to golf course communities and gone are many of the short-season wetlands necessary for wading birds.

"It's a real international treasure," said current sanctuary directory Keith Laakkonen. "(But) we've lost a lot of these shorter-period hydro-wetlands that these wood storks really depend on."

So where are the storks nesting?

Mostly on farm fields in areas like north Florida, Georgia and the Carolinas.

There, rice fields and other converted lands offer better feeding conditions as it appears more fish are available there than here in the historic Everglades system.

Even habitat within the sanctuary can turn foul for the birds.

"All of a sudden the landscape isn't as good for wood storks, so they've moved into northern Florida, Georgia and South Carolina," Laakkonen said.

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His concern is that the farm fields may be converted to another use in the future, and that what seems like ideal feeding conditions in those areas could go away one day.

That would make Corkscrew Swamp Sanctuary and important backup for the species, he said.

"A lot of these places where they're nesting are not natural areas and they are close to the coast," Laakkonen said. "So, one hurricane could make a big difference is those areas."

Lauritsen said the story of wood storks in the Corkscrew Swamp Sanctuary shows a broader impact to Southwest Florida's ecology.

"It's a warning about what we've lost around the area and what the core foraging habitat has become," Lauritsen said.

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This article originally appeared on Fort Myers News-Press: Woods storks once nested at SW Florida sanctuary. What happened?