Eagles flock to Metzger Marsh
Lowering wetlands leaves some fast fish food for carrion-eaters
An unusual, awesome number of bald eagles collected at Metzger Marsh in Jerusalem Township last week, likely answering a dinner bell that inadvertently rang because of ongoing wetlands work there.
Jim Hays of Curtice saw 50 to 60 eagles there Monday, 20 on Tuesday, and 25 on Wednesday. He recorded the happening on video, estimating that 90 per cent of the birds were unpaired or nonbreeding immatures.
"That's a tremendous number of eagles that people should know about and go see," said Mark Shieldcastle, project leader at the state's Crane Creek Wildlife Research Station in Ottawa County. The station oversees eagle conservation programs for the Ohio Division of Wildlife.
The 908-acre marsh is cooperatively managed by the state, which controls 558 acres, and the U.S. Fish & Wildlife Service, which controls 350 acres as part of the 9,000-acre Ottawa National Wildlife Refuge complex. It is located off State Rt. 2 at the well-known Bono Curve.
Shieldcastle theorized that work to control phragmites, an invasive pest-plant that encroaches on stands of marsh plants valuable to wildlife, is behind the gathering of eagles. "It's because of the drawdown of the water in the marsh. It's isolated fish out there and it's easy pickings for the birds."
Lake Erie water levels are up somewhat this summer and recent heavy rains have added flow at Crane Creek estuary, another traditional summer eagle collection-point, the biologist said. "You don't have the mudflats there that the birds normally feed on."
Immature eagles typically gather near the mouth of the Sandusky River this time of year as well.
Metzger was drawn down this spring to allow wildlife crews to move in and treat the increasingly dense stands of phragmites, or common reed, a wispy-headed grass that can grow to 12 feet but which provides little food or cover to waterfowl, waterbirds, or other marshland wildlife. Such work accomplishes several objectives.
"It's a good example of how the overall wildlife management plan for the marsh has many benefits for wildlife year-round. It's not just about duck hunting," Shieldcastle said.
The reduction of phragmites will allow populations of beneficial native plants to flourish again and provide more food and nesting cover.
The exposed mudflats in turn attracted great concentrations of shorebirds - sandpipers, and such - during the spring migrations. Shorebirds love to feed on tiny worms, slugs, snails, and such wiggling in the surface mud.
Exposed, dead fish left behind from drawdown are attracting eagles, which are as much carrion-eaters, like turkey vultures, as they are hunters.
In August the mudflats and exposed sandbars likely will attract terns - common, Forster's, and Caspian - and such uncommon gulls as Bonaparte's and greater black backed. Late summer/early autumn migrations should see a return of passing shorebirds to the flats, as well as swallows and purple martins, Shieldcastle said.
As for the eagles, Ohio's birds are doing famously. In 2004 108 nests were confirmed, of which 73 produced a record 127 young.
Some of this spring's early-hatched eaglets are flying on their own for the first time.
Note that eagles are precocious in their early growth, that is, the young reach adult size by the time they are ready to fledge. It takes about five years, however, before they develop the classic white head and tailfeathers of adults.
Shieldcastle said that the production of eaglets actually was even higher, but at least 13 young birds have been killed since May as storms have destroyed at least 11 nests. Eagle mates, however, are strongly territorial and typically rebuild lost nests nearby.
Lowering wetlands leaves some fast fish food for carrion-eaters
An unusual, awesome number of bald eagles collected at Metzger Marsh in Jerusalem Township last week, likely answering a dinner bell that inadvertently rang because of ongoing wetlands work there.
Jim Hays of Curtice saw 50 to 60 eagles there Monday, 20 on Tuesday, and 25 on Wednesday. He recorded the happening on video, estimating that 90 per cent of the birds were unpaired or nonbreeding immatures.
"That's a tremendous number of eagles that people should know about and go see," said Mark Shieldcastle, project leader at the state's Crane Creek Wildlife Research Station in Ottawa County. The station oversees eagle conservation programs for the Ohio Division of Wildlife.
The 908-acre marsh is cooperatively managed by the state, which controls 558 acres, and the U.S. Fish & Wildlife Service, which controls 350 acres as part of the 9,000-acre Ottawa National Wildlife Refuge complex. It is located off State Rt. 2 at the well-known Bono Curve.
Shieldcastle theorized that work to control phragmites, an invasive pest-plant that encroaches on stands of marsh plants valuable to wildlife, is behind the gathering of eagles. "It's because of the drawdown of the water in the marsh. It's isolated fish out there and it's easy pickings for the birds."
Lake Erie water levels are up somewhat this summer and recent heavy rains have added flow at Crane Creek estuary, another traditional summer eagle collection-point, the biologist said. "You don't have the mudflats there that the birds normally feed on."
Immature eagles typically gather near the mouth of the Sandusky River this time of year as well.
Metzger was drawn down this spring to allow wildlife crews to move in and treat the increasingly dense stands of phragmites, or common reed, a wispy-headed grass that can grow to 12 feet but which provides little food or cover to waterfowl, waterbirds, or other marshland wildlife. Such work accomplishes several objectives.
"It's a good example of how the overall wildlife management plan for the marsh has many benefits for wildlife year-round. It's not just about duck hunting," Shieldcastle said.
The reduction of phragmites will allow populations of beneficial native plants to flourish again and provide more food and nesting cover.
The exposed mudflats in turn attracted great concentrations of shorebirds - sandpipers, and such - during the spring migrations. Shorebirds love to feed on tiny worms, slugs, snails, and such wiggling in the surface mud.
Exposed, dead fish left behind from drawdown are attracting eagles, which are as much carrion-eaters, like turkey vultures, as they are hunters.
In August the mudflats and exposed sandbars likely will attract terns - common, Forster's, and Caspian - and such uncommon gulls as Bonaparte's and greater black backed. Late summer/early autumn migrations should see a return of passing shorebirds to the flats, as well as swallows and purple martins, Shieldcastle said.
As for the eagles, Ohio's birds are doing famously. In 2004 108 nests were confirmed, of which 73 produced a record 127 young.
Some of this spring's early-hatched eaglets are flying on their own for the first time.
Note that eagles are precocious in their early growth, that is, the young reach adult size by the time they are ready to fledge. It takes about five years, however, before they develop the classic white head and tailfeathers of adults.
Shieldcastle said that the production of eaglets actually was even higher, but at least 13 young birds have been killed since May as storms have destroyed at least 11 nests. Eagle mates, however, are strongly territorial and typically rebuild lost nests nearby.
