In the 1980s, Dennis Smith used to fish for alewives on Mount Desert Island. Now, he’s helping his fellow feathered alewife hunters do the same.
Smith and partner Karen Zimmerman build osprey nest platforms, but don’t picture them shimmying up a tall tree with twigs in their mouths. They construct the platforms on the ground and use a design that’s a little hardier than sticks on a broken treetop.
Smith and Zimmerman use copper sheathing, stainless steel straps and wire mesh to create a 53-inch square platform that is both durable and porous. For a finishing touch, they scatter around a few sticks to nudge passing ospreys to think about nesting.
“They take to the nest a lot faster if there’re already sticks in it,” Smith said.
Their first foray into osprey platforms stemmed from a birthday request for a family member at the estate Smith manages. Smith said the experience was so rewarding that he and Zimmerman went into business soon thereafter.
“Raised some [young] year one,” Smith said.
They’ve since erected three more platforms on Mount Desert Island, and Zimmerman expects more customers soon.
“The response to our direct mailing is astounding,” she said.
Smith said their platforms are designed to withstand 80 mph winds. Each platform is guaranteed for ten years, but he believes they’ll last longer and serve not only current osprey occupants, but future generations as well.
Once they finish constructing each platform, they hire a retired Bangor Hydro pole-setter to erect a pressure-treated telephone pole at the proposed nesting site and place the platform on top.
After building the first nest, Smith said he understands the appeal of having ospreys in the backyard. At the first platform site, everyone became enthralled with the osprey nesting process: watching a pair begin to build their nest, the eggs hatching, parents hunting for their young, and young trying out their wings and eventually leaving the nest.
“It’s great entertainment,” Smith said.
But aside from being entertaining, the nesting platforms may help reverse a perceived decline in Maine’s osprey population, said Charlie Todd, a raptor biologist for the Maine Department of Inland Fisheries & Wildlife.
“It might help remedy the situation,” Todd said.
Osprey populations, like those of eagles, plummeted with the widespread use of DDT in the sixties and seventies. While many states placed ospreys on their endangered or threatened species lists, Maine had a larger population than most and had further to drop.
After DDT was banned, ospreys initially rebounded more readily than eagles, mainly because of their superior skills as hunters and nest-builders.
“Whatever the eagles try to do, the ospreys are more versatile,” Todd said.
As nesters, ospreys have a lot going for them. They aren’t as shy of humans as eagles, so they don’t mind nesting where eagles fear to tread: near houses, along highways, or even perched atop navigation markers and cell phone towers. Being social creatures, ospreys aren’t bothered nesting near each other, either; Smith said he’s known pairs to nest within a hundred feet of another nest. And because they’re such successful hunters, ospreys can build their nest inland and commute to saltwater. Still, a nest near the ocean is considered ideal, as ospreys have been known to fish right out of their nests.
But as eagles slowly have rebounded in Maine, osprey numbers have declined. These two facts may not be coincidence. Ospreys are migratory birds; if they leave their nests for the winter, they could return in the spring to find their nests taken over by eagles that stay in Maine year-round.
“It’s pretty clear they bother each other a lot,” Todd said.
And ospreys may be losing the battle. While Maine still is considered an important osprey stronghold on the Eastern Seaboard, Todd said osprey sightings have been down, especially Downeast.
And it isn’t just competition that’s driving those numbers down. The same fishery decline that stopped Smith from alewife harvesting in the eighties (WWF April 2007) also may be curtailing successful osprey nesting. Alewife numbers must rebound, Todd said, or osprey populations will decline, no matter how many nesting platforms are built.
“If food availability is limiting, even the poshest platform won’t tempt them,” he said.
But platform-building efforts like Smith’s and Zimmerman’s always will benefit local osprey populations, Todd said.
“It gives them one more niche,” he said.
Todd said it’d be best for all involved to be considerate when deciding where to place a platform. The nesting site should be away from power lines and located on a quiet part of the property, away from neighbors. From his experience, Todd warned that osprey young are very, very vocal if they feel their meal is late.
For more information on osprey platforms, visit www.raptornests.com.