Ospreys nest in record numbers at Indian River County's Blue Cypress Lake

BLUE CYPRESS LAKE — "There's the tag; I see it," Donna Halleran shouts above the purr of a Honda outboard engine.

I don't see anything except a gnarled cypress tree with a massive clump of sticks and Spanish moss where the top of the tree used to be.

I sure as heck don't see a silver dollar-sized brass tag nailed to the trunk, half obscured by more Spanish moss.

Then an osprey head pops up out of the clump. It's a nest all right, and I dutifully enter into the log what the three bird-watching pros from the Pelican Island Audubon Society in the boat already had surmised: Nest No. 227 is occupied.

By the time I'm done scribbling, Jim Shea of Vero Beach already has steered the boat toward the GPS coordinates of nest No. 228. Halleran, the chapter's vice president, and Richard Baker, the president, are already homing in on the next tag.

And ospreys — dozens of them, perhaps hundreds over the course of the day — are flying above us with fish in their talons or sitting on nests with eggs or young chicks.

So far this month, Audubon volunteers have counted 313 occupied osprey nests in trees ringing the 6,555-acre lake in western Indian River County. And there are 12 known nests they couldn't reach by powerboat and will have to check on kayaks.

That's more than the 311 occupied nests counted last year and the most nests Audubon has counted since it began the annual Blue Cypress Lake survey five years ago.

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"There are a lot of new nests this year," Halleran said. "We don't know if it's offspring returning to build nests were they were born. We lost some nests to Hurricane Irma, but we've got a lot of new ones, too."

The natural freshwater lake has the highest concentration of osprey nests in the world, said Baker, former director of the Florida Medical Entomology Lab in Vero Beach who's been studying ospreys at Blue Cypress since 1990. "At least no one's come forward to dispute it, and we've had experts here from all over."

That's because, Halleran said, "nowhere else in the world do you see ospreys nesting so close together."

One the north side of the lake, she added, "we saw two nests in the same tree."

Nester's market

Why do so many ospreys, which typically return to the same nest year after year, build their homes at Blue Cypress Lake?

Like they say in the real estate biz: location, location, location.

Location: The nesting sites are perfect. The trees that give the lake its name grow in the water, providing protection for the nests, particularly from raccoons, Baker said.

Most of the trees, which can be up to 500 years old, have had their tops blown off by lightning, creating perfect platforms for nest-building.

Location: Several lakes and man-made marshes nearby, including Stick Marsh and the new Fellsmere Water Management Area (aka Headwaters Lake) supply plenty of fish.

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Location: "It's serene," Halleran said. "Most of the area around the lake is very undeveloped. There are very few powerboats on the lake."

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Even Treasure Coast Seaplanes’ Cessna 206G Stationair, which lands in the lake periodically for tours, "doesn't seem to bother the ospreys," Halleran said. "It lands in the middle of the lake, and they're mostly around the edges."

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The Vero Beach tour company consulted with Audubon, said Sheena Hoover, who owns the business with husband Michael, "and we do our best not to disturb the ospreys, especially during nesting season."

'Tis the season

If you want to see the ospreys, you'd better hurry.

"They'll almost all be gone by the summer," Baker said.

Ospreys tend to leave the area in mid- to late summer, flying to South America for a short time before returning in the fall and starting the nesting process all over again.

"The best way to see the ospreys is by kayak or canoe," Baker said. "You can get really close to the nests without disturbing the birds. And if they stay put, you'll see more of them."

You can get close, but not too close, Baker said. Scaring an osprey off its nest, for example, is considered harassment.

From a kayak, Halleran said, "you can really see the cypress trees, which are beautiful all by themselves."

Back on the boat ...

Meanwhile, we're looking for another tag on another tree.

Halleran, who's got eyes like the osprey whose nest we're approaching, has spied the tag. Baker, in the bow of the boat, is fighting his way through cypress limbs and moss trying to read the number."

We made the tags small so they wouldn't be obtrusive," Halleran says later as we're unpacking the boat.

"They could have been a little bigger," Baker says as he walks by, toting several pairs of binoculars.

Get a grip on ospreys

Unique among hawks, ospreys have reversible outer toes to grasp fish with two toes in front and two behind, as well as barbed pads on the soles of their feet to grip slippery fish. They carry their catch headfirst for less wind resistance.