Oh, what a tangled, deadly web osprey weave in building nests


WITH HEADS nearly the size of their bodies, the week-old osprey chicks just stare at me as I stand on tiptoe on the channel marker 8 feet above the Severn River.

The anxious parents flap nearby, attempting to scare me off with their squawks and chirps. Not to worry; as an afraid-of-heights, can't-swim human, I am doing a good job of frightening myself.

U.S. Fish and Wildlife Service employees wait in their boat below ready to activate a search-and-rescue mission.

While the chicks are impossibly cute, what is hanging a short distance from their heads is not.

Old discarded plastic and fishing line are woven into the nest. With luck, the chicks will grow and fly off without ever coming into contact with the trash. But too often, the chicks or their parents get tangled in the stuff and strangle.

Last year, biologists found a grown or nearly grown bird ensnared in line attached to a nest near St. Helena Island in the Severn. The bird had been unable to free itself and died.

"This stuff is bad," says Peter McGowan, a Fish and Wildlife environmental contamination biologist. "It's a killer."

And, unfortunately, there's more and more of it on Maryland's waterways.

An osprey nest near the Sandy Point State Park marina is filled with fishing line, leader and hooks. Half the nests along the Magothy and Patuxent rivers have monofilament line threaded among the tree branches and grasses.

And here along the Severn, plastic supermarket bags, line and strips of blue tarp are as much a part of the nests as the chicks themselves.

"We started seeing an increase in the amount of fishing line in 2000, when we were conducting a contamination study," McGowan says. "We didn't see contamination. We did see chicks wrapped up in fishing line."

The Chesapeake Bay is home to 3,600 breeding pairs, making it one of the country's largest nesting populations. Biologists estimate that 1,600 of the pairs live in Maryland.

When it comes to building materials, osprey don't discriminate. Humans, apparently, aren't discriminating enough when they discard trash.

McGowan and his partner, Randy Loftus, check on the osprey twice a season. Nothing surprises them.

As we motor up to one nest on Marker No. 5, what appears to be a pair of tattered Fruit of the Looms waves at us weakly.

"We've found teddy bears in nests on the South River, plastic flowers, even a bra," says McGowan, laughing.

Then, growing serious, he walks to the back of the boat and opens a bin. Inside is some of the nesting material they've been able to tug or cut out of nests, almost all of it plastic-based: the net bags that hold onions, pieces of erosion-control cover from a nearby waterfront mansion and purple ribbon.

"Last year on the South River, every nest had this balloon ribbon," McGowan says.

Osprey are the only North American raptor to dine almost exclusively on fish. The migratory birds fly to South America for the winter and return each spring to breed.

The fish-rich bay looks like a big 24-hour diner to the returning birds, and the channel markers and other manmade structures are perfect motels. Scientists estimate 90 percent of the birds prefer structures to trees.

The osprey population took a huge hit in the period from 1950 to 1970, when pesticides and other contaminants caused the thinning of eggshells. All but 10 percent of the nesting pairs between New York and Boston died. But by banning certain chemicals and restoring habitat, the birds rebounded.

Now, they face another hurdle created by humans.

Federal and state biologists have posted signs at marinas around the Chesapeake Bay reminding the nearly 46,000 Marylanders with pleasure boat decals and 200,000 resident and visiting anglers to take their trash with them.

But from the looks of it, the message isn't sinking in.

Lots of folks want to be on the bay. That's understandable. Just look around at how developers clear-cut trees to make room for garish, "look-at-me" houses.

The osprey are part of the Chesapeake picture.

It wouldn't kill all of us to be a little more careful.

One thing is for certain, our carelessness will kill the osprey.

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