Ospreys are reintroduced to Iowa

Posted: Wednesday, July 25, 2001

IOWA CITY, Iowa (AP) -- As locations go, it would be hard to find a better home -- a sweeping view of the Saylorville Reservoir, the Coralville Reservoir, maybe the Cedar River.

Of course, the view would be pretty good no matter what. The feathered residents in hacktowers there could read the fine print from a newspaper at 100 yards, if they could read.

That's one trait ospreys don't possess, though. Instead, they rely on that spotting scope vision, fishhook sharp talons and a propensity to go into the water after fish to survive.

And these impressive predators have brought their act to Iowa.

The return of the ospreys is human-induced at this point on the Saylorville Reservoir area in Polk and Boone Counties and the Cedar River in Black Hawk County.

The Coralville Reservoir release in Johnson County was held up a few days to allow a young eagle held there to acclimate herself to flight.

A network of local fund-raising, volunteer monitors and coordination with the U.S. Fish and Wildlife Service, Department of Natural Resources and county conservation boards all mesh to welcome this 'fish eagle,' as it is known.

A crowd of 100 showed up for the Polk County's Jester Park release. Nearby, a TV monitor lets people keep track of activities inside the 30-foot tall hacktower.

Not an eagle at all, an osprey is related more closely to the kite family. At 2 1/2 to 4 1/2 pounds, it is often less than half the size of a bald eagle. They are top-of-the-line predators, though, custom-made for diving below the water line after fish.

A special eye membrane helps them track down their finned prey. Their feet are made for gripping slippery fish. One toe actually swivels backward to clamp a fish 'torpedo' style as ospreys fly away to enjoy their meals.

While no nests have been documented in Iowa's past, verbal histories from the native Omaha and Winnebagos refer to ospreys in northwest Iowa. Earlier releases in Minnesota have also shown results in northwest Iowa.

''Two Minnesota-released birds established an Iowa nest on the Little Sioux River,'' says Pat Schlarbaum, DNR details wildlife diversity technician. ''Horrendous storms ruined it, though. The ospreys did stay around and we're hopeful they'll make another attempt next year.''

With a reservoir system creating large lake settings, biologists envision an osprey range across Iowa.

''We anticipate they will imprint -- recognize where they first flew -- where they took their first meals,'' explains Schlarbaum.

''Males often return to within 20 miles of where they imprint as 'home.' With the marsh restoration in northwest Iowa, with the reservoir system now in place, perhaps ospreys returning to Iowa is a reward, of sorts,'' he said.

Much like peregrine falcon reintroduction of a decade ago, the young ospreys are kept in a hacksite above their preferred habitat. Feeding chutes and one-way observation mirrors keep human interaction kept to a minimum.

Brought to Iowa at about 42 days old, they take their first test flights at around 53 days. As they begin taking fish on their own, the human presence around them will shrink even further.

In the meantime, that volunteer network is vital.

''Volunteers do all the feeding and observing when the birds are in the (hack) tower,'' says Sue Davies, central Iowa volunteer coordinator. ''Once the birds have fledged, (volunteers) still come out and spot the birds -- where they're flying, if they are fishing yet, just how the birds are doing.''

She says volunteers logged about 2,000 hours of 'osprey time' last year.

The Coralville site is receiving ospreys for the fifth straight year. In Black Hawk County, they have come in four years. This is the second year for Saylorville Reservoir.

''Ospreys are closely associated with larger bodies of water,'' explains Jodeane Cancilla, Macbride Raptor Project director. ''We are optimistic that birds will return to nest around here. Nature works in her own time. It'll happen when it happens.''

With the human touch, that return gets a well-deserved boost. And then, 'fish hawks' will be soaring over the waters of Iowa possibly in the same area as a reluctant eagle that isn't ready to leave home, either.

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