They’re back, but now osprey nests are endangered

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By EVAN KREAGER
Capital News Service
LANSING — The osprey, a species of special concern that has rebounded in Michigan over the past half-century, now faces a new threat.

Ospreys rest in their nest at the top of a tower. (Image: Osprey Watch of Southeast Michigan)

Ospreys rest in their nest at the top of a tower. (Image: Osprey Watch of Southeast Michigan)


A demand for easy communication and power distribution increased the need for cellular and utility towers. Ospreys nest on tall objects and will nest in these towers anytime they can, said Sergej Postupalsky, a Wisconsin-based ornithologist who has specialized in osprey research for 50 years.
But the nests obstruct access to towers and lines. The nests also weigh down towers and lines, and in some instances even cause fires So utility workers often move them so that they can work. But moving the nest frustrates osprey, who return to the same nests year after year.

“Some of these birds have been using the same nests for up to 10 years,” Postupalsky said.
Postupalsky works as an independent raptor specialist with groups like the Osprey Watch of Southeast Michigan.
A nest is visible in the bottom corner of this tower near Maple River in Michigan. (Image: Osprey Watch of Southeast Michigan)

A nest is visible in the bottom corner of this tower near Maple River in Michigan. (Image: Osprey Watch of Southeast Michigan)


This is the latest challenge to a bird of prey that has had plenty of them.
Legal protection for them didn’t come until the 1950s, Postupalsky said. Over the past decade or so, some of these laws have become a bit more lenient. If there are no birds or eggs within a nest, it is legal to remove it.
Only about one-third of fledging ospreys survive to be three years old, when they generally mate and return to the nest for the first time, Postupalsky said.
“For birds of prey that choose to reuse their nests year after year, these laws should not apply,” he said regarding moving or removing nests. “It’s not illegal, so the DNR can’t do anything about it.”
The problem is the law, said Jim Kaiser, founder of Osprey Solutions, a raptor research and management company based in Seattle.
“The meat of the matter is simple: because the utilities are allowed to remove the nests, sometimes they do,” Kaiser said.
Ospreys were once hunted, persecuted and driven away. They were looked at as vermin.
No one has pinpointed why osprey numbers were so low for so long, but there is no shortage of ideas – everything from large-scale use of pesticides to increased habitat destruction. But they are coming back.
In the southern half of Michigan’s Lower Peninsula, where reintroduction has been particularly difficult, the goal in 2000 was to have at least 30 breeding pairs by 2020. It was surpassed nearly a decade earlier than expected, said Barb Jensen, a founding member of the Osprey Watch of Southeast Michigan. There are approximately 38 pairs in the area now.
Ospreys nest on every continent except Antarctica, Kaiser said. Conflicts with nests on towers are likely to rise.
The Osprey Watch of Southeast Michigan, a group of volunteers involved in the reintroduction of the bird to the area, along with Postupalsky are working with tower companies to educate workers on the subject.
They explain how to check a nest without disrupting it, how to move and replace a nest, and that just because the nest isn’t occupied does not mean that it’s done being used.
There is a lot of cooperation, but also miscommunication, Jensen said. “We’re just trying to get everybody on the same page.”
“This is what we’re trying to figure out,” she said, “how best we can work with these companies. The power companies have done a lot to try to accommodate these birds as best as they can.”
The birds themselves are big — 22-25 inches long with a wingspan of 4.5 to 6 feet, and a weight of approximately four pounds, according to the Osprey Watch website. They eat fish.
Many towers have signs warning of nests that are protected by federal law. (Image: Osprey Watch of Southeast Michigan)

Many towers have signs warning of nests that are protected by federal law. (Image: Osprey Watch of Southeast Michigan)


While the tower companies are generally cooperative and protective, it is often the contractors and subcontractors that tamper with the nests, according to Postupalsky.
DTE Energy, a Detroit-based utility, has its own wildlife coordinator. Consumers Energy has a similar focus on environmental stewardship and wildlife management.
“We do a lot internally to educate our employees [about proper handling],” said Jason Cousino, field safety specialist for DTE’s River Rouge power plant. “Communication went out to our employees specifically because of this.”
The company has donated utility poles for nest platforms and worked with local eagle scouts to build nests. They have also donated a transmitter to track Osprey migration routes, working directly with the Osprey Watch of Southeast Michigan.
Kaiser would like to see a workshop convened in the near future to help identify problems with managing these birds on cell towers.
Cousino recognizes the drive behind that wish.
“That’s what this osprey group is trying to do,” Cousino said, “educate people.”
Evan Kreager is a reported for Great Lakes Echo.

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