Unamused, the osprey mama circled and squawked and even dove at researchers Monday morning as they carefully lifted her two chicks from their nest south of Laurel.
Marco Restani, a professor from St. Cloud State University in Minnesota, and Kayhan Ostovar, a professor of environmental science at Rocky Mountain College, with help from RMC students, worked quickly to band and take measurements of the chicks.
They had the babies safely back in the nest within a half hour.
The banding project, Ostovar said, is part of an ongoing study on the quality of the Yellowstone River by focusing on osprey, a fish-eating raptor that plunges feet-first into water to snag its prey.
The study includes examining osprey blood to check for levels of heavy metals, like mercury, which could end up in their bodies from fish consumption, Ostovar said.
Coal burning is a main source of mercury, which can enter the river and food chain through a variety of methods, he said.
The Osprey Project, now in its third year, is being conducted by the Yellowstone River Research Center, which is directed by Ostovar and Restani, in partnership with the Yellowstone Valley Audubon Society and other participants.
The researchers banded chicks from two other nests in the Laurel area on Monday and plan to visit 20 more nests this year, Ostovar said.
At the end of this season, the project will have sampled a total of nearly 60 nests and banded “well over” 100 chicks in the past three years, he said.
The project would like to continue banding chicks for another two years but this year is probably the last time researchers will draw blood, Ostovar said. The blood sampling is to establish baseline data, he added.
The study is costing about $30,000 a year, with major grants coming from the Cinnabar Foundation, the Royal Bank of Canada and a U.S. Geological Survey grant through Montana State University Bozeman’s Montana Water Center, along with in-kind contributions, Ostovar said.
Steve Regele, YVAS’s president, said the organization assists by coordinating volunteers to monitor the osprey nests. “It’s been a really good collaboration,” he said.
RMC students Matt DeWit, of Opheim, and Linnea Warlick, of Warren, N.J., both seniors, also are helping with the research this year.
DeWit, an environmental sciences and environmental studies major, said there are 85 osprey nests along the Yellowstone River from Gardiner to Miles City. About half are occupied and produced chicks this year, he said.
DeWit, who will be going to graduate school, has been monitoring 14 nests, taking photographs of fish prey and trying to calculate the chicks’ success rates.
DeWit, said this year’s storms, especially the hail storms in the Billings area, have been rough on osprey.
Some nests blew down and some adults left their nests, abandoning the eggs, DeWit said.
Warlick, a biology and equine major who plans to become a veterinarian, is studying osprey blood samples seeking to evaluate stress levels by looking at metal concentrations and white blood cells.
“It’s been kind of a learning experience. I’m really excited about it,” Warlick said.
The osprey banded on Monday south of Laurel came from a new nest this year. The old nest, which was located on a power pole owned by the Yellowstone Valley Electric Cooperative, blew down last year.
The new nest is atop a platform on a pole free of power lines but near where the former nest was located.
The electric co-op, one of the partners, used its bucket truck to lift the researchers to the nest.
YVAS donated $1,500 for the new nesting pole and platform.
Osprey have been nesting in this particular area for at least 15 years, making it one of the oldest nests in the valley, Ostovar said. “It’s great to know they came back,” he said.
The new nest is located on property owned by Dick and Jena Bell, who run the Osprey Outpost, an antique store about two miles south of Laurel off of Highway 212.
Dick Bell said they have enjoyed observing the osprey for years.
Restani, who spends the summer in Red Lodge, is a YVAS board member and is federally-licensed to band osprey, drew a blood sample from the wing of one of
the chicks, but banded, weighed and measured both babies.
Each bird weighed about three and a half pounds and nipped at their handlers before Restani covered their heads with a hat to calm them during the exam.
One of the bands is a metal ring with a number assigned to the particular osprey, while a second band is green with a number big enough to be seen by a monitor.
Restani pronounced both chicks as “great, super healthy.”
Osprey produce between one to four eggs. The pair south of Laurel had two chicks.
When the exam was compete, Restani picked up one of the chicks and let a few of the observers, including eight-year-old Will Orley, of Red Lodge, hold it briefly.
Orley has “been very interested in osprey,” said his mother, Erin Orley.
The 30-day-old chicks will fledge in about a week, Ostovar said, and migrate south to the Gulf of Mexico or South America, where they will stay for three years before returning.
Osprey nearly became extinct in the United States during the 1950s to 1970s because of pesticide use.
After the banning of DDT in 1972, osprey numbers began increasing. The birds began repopulating the Yellowstone River watershed in the 1980s.