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Monday, Nov 12, 2018
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Port Tampa Bay has to dredge with care in nesting season

— A dozen pairs of black and white shorebirds with brilliant orange beaks walk the shoreline on an island in Hillsborough Bay, preparing to nest. It’s an iconic spring scene in central Florida.

This man-made island whose shores are flanked with massive bouquets of native blooming prickly pear cactus, mangroves and invasive Australian pines isn’t just a chunk of paradise for birds, however. It is a construction zone, a depository for tons of sand that will soon be dredged from Big Bend Channel to allow coal-laden ships to make their way to the Tampa Electric Co.’s nearby power plant.

TECO will begin dredging the channel in about a month, work that is simultaneous with nesting season, which runs April to August. The work must be carefully orchestrated so as not to interfere with birds, which are protected under federal law and have faced declining habitat over the decades.

As beaches have become more crowded with people and coastal lands have been increasingly developed for homes, roads and businesses, Florida’s shorebirds have been squeezed into smaller and smaller spaces. Those circumstances have led to more urgency through the years to protect the remaining land masses where they nest and thrive.

Getting the job done and protecting the American oystercatchers and other birds that choose to nest on spoil islands requires a solid partnership between business and nature, one that has worked well, by all accounts, for more than 30 years.

Islands 2D and 3D, near the eastern shore of Tampa Bay, were created by Port Tampa Bay as places to dump sand dredged from shipping channels. Thousands of birds use the islands year-round as places to loaf and forage. In spring, during nesting season, they are especially lively.

The Port Tampa Bay islands, along with several others in that area of the bay, are so important to the future of the birds that they’ve been deemed as globally significant nesting areas by BirdLife International. BirdLife is the world’s largest conservation partnership with more than 13 million members.

Port Tampa Bay endeavors to limit any work taking place during nesting season, when mangrove branches are heavy with nests and least terns and oystercatchers zero in on those inviting stretches of bare sand. But there are times when the conflict can’t be avoided.

On 3D, the U.S. Army Corps of Engineers has contractors finishing up work to raise a 3-mile-long levee from 23 feet to 40 feet so the 500-acre island can handle dredge material being scooped from the bay bottom over the next 20 years or so. Bird monitor Lorraine Margeson works full time to ensure that birds and equipment don’t mingle, flagging nest areas and assisting in rerouting equipment when necessary.

In preparation for ­TECO’s 2D project, port officials tried something new this year to determine if work on the island would affect the birds. They sent in a drone.

“It was a test experiment for our engineering and surveying department to try and measure the volume” of space available on 2D for dredge spoil, said Jackie Julien, environmental supervisor for Port Tampa Bay. “I was on site on behalf of Audubon to oversee it. It went well. No birds were disturbed at all.”

Taking direction from Audubon Florida, which focuses on protection of birds and habitat protection, the TECO contractor is now flooding the interior of island 2D to deter birds from nesting. A path used by the contractors to reach that interior is covered with pine straw, another deterrent to birds who prefer that sandy motif.

In a perfect world, the birds will carry on with their spring nesting and the dredge work will move along at a good clip. “If you end up having to relocate the work you are doing or shift it around to avoid the birds, that’s just part of the job,” Julien said.

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While there are about a dozen pairs of oystercatchers preparing to nest alongside the TECO construction site, less than one chick per nest is expected to survive to fledge, said Mark Rachal, bird sanctuary manager for Audubon Florida. So every nest is an important one.

Boating around the island donning binoculars and keeping a journal close at hand to document his findings, Rachal said that when it’s time to nest, the birds scope out the area and choose the beaches that give them a clear view of the shoreline. “Dredging almost mimics beaches after a storm.” That, to the birds, is an appealing nesting spot, he said.

The oystercatchers will be joined on island 2D by the tiny least terns, majestic black skimmers, long-legged black necked stilts and a plethora of gull species before summer’s end. Audubon is hiring a ­full­- time bird monitor to work around the island while the work is underway.

“The birds will start nesting in earnest next month,” said Rachal, and by then, the interior of 2D should be flooded. Already, a dredge boat is perched off the coast of the island, pulling water from the bay, then piping it into the sandy middle.

“The black necked stilts are maddening because they nest right at the water’s edge,” Rachal said. “So once the contractor floods the island, the level can’t deviate or nests will get washed out.”

Before work ever begins, Port Tampa Bay, Audubon, the Florida Fish & Wildlife Conservation Commission, the U.S. Fish & Wildlife Service and the contractors meet to go over the rules.

Ann Paul, Audubon’s regional coordinator, conducted a class recently with the crew from contractor Orion Marine Construction, “setting them up for success” with this project by showing them bird identification photos, going over the laws that protect the birds and the protocol for keeping them safe.

“These guys are really good. They’ve changed course many times and even shut down the project when they couldn’t work around the birds,” she said of Orion.

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The port is emphasizing the need for people to stay off the islands, which are always closed to the public. Not only is it illegal to disturb the birds, it is also illegal to trespass on the construction sites.

The TECO dredging project should wrap up within about two months.

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