Osprey Population Increasing in MT, But the Wildlife Management Success Story Includes Some Conflict

The recovery of the osprey population, a raptor that returns from the south each spring to the western 2/3s of Montana, is a success story that began almost 50 years ago when a widely used pesticide, DDT, was banned.

But this wildlife management success story comes with some conflict. Younger osprey in search of nesting sites to breed and hatch eggs will build nests on power poles, causing outages and putting the birds at risk of electrocution.

NorthWestern Energy crews were in Augusta in early June to install raptor nest deterrents on power poles, along with a nesting platform to encourage osprey to choose a safe nesting site.

"We don't know if historically osprey had been in the Augusta area or not, if the species is colonizing a new area in Montana or recolonizing," said NorthWestern Energy Biologist Marco Restani.

The new, or perhaps returning, Augusta-area winged residents built a nest on a power pole this spring just outside the substation serving the community. The nest caused a fire on the pole and falling nest debris damaged equipment and caused a power outage.

Osprey build nests by dropping sticks to their chosen site while in flight.

"Traditionally, they look for dead trees, snags, with the tops broken off for a nesting place," said Restani. "Power poles, especially those with cross arms, are often the choice of younger osprey looking to establish a new nesting site. It is dangerous for the birds and it is damaging to NorthWestern Energy's system."

Deterrents are PVC pipes that are secured above power poles' cross arms. When osprey drop sticks in flight on a power pole, the PVC pipe prevents them from hitting their target and the sticks fall to the ground. Five are now installed in the Augusta area, along with a raptor nesting platform to encourage the birds to nest in the safe location.

NorthWestern Energy relies on customer reports of osprey or other raptors beginning to build nests on power poles and other equipment to proactively remove the sticks before nests are complete and eggs are laid.

"The public has been extremely helpful with this effort," Restani said.

Another threat to osprey, ravens and other avian species also requires action by the public.

Unsecured baling twine picked up by birds and used in their nests has devastating, deadly consequences.

The birds can get tangled in the twine and cannot escape.

This spring the male of a pair of osprey that nested on a platform near Whitehall died after its talons caught in part of a coil of baling twine the birds had picked up and used in their next.

"It's really distressing to have this result," Restani said. "The crew called to remove the dead male said the female had abandoned the nest, which did have a couple of eggs in it."

Baling twine should be secured in a covered container and disposed of properly to prevent osprey or other birds from picking it up to use in nests.

The Yellowstone Valley Audubon Society has a Twine Collection & Recycling Site in the Laurel area. For more information on the project, go to https://yvaudubon.org/baling-twine-recycling/.