Hawk Ridge eagle presents golden opportunityThe golden eagle was cruising south at mid-morning on Monday, perhaps migrating toward the bluff country of southeastern Minnesota.
By: News Tribune staff, Duluth News Tribune
The golden eagle was cruising south at mid-morning on Monday, perhaps migrating toward the bluff country of southeastern Minnesota.
Its day soon took a dramatic turn.
A couple of hours later, the handsome adult male was being fitted with a $3,500 GPS satellite transmitter in the woods behind Hawk Ridge Bird Observatory in Duluth.
From now on, the GPS transmitter on golden eagle No. 53 will record its position once an hour, enabling birders with Audubon Minnesota to track its location all year long, perhaps for several years.
“I just got lucky,” said Frank Nicoletti, banding director at Hawk Ridge, who trapped the eagle about 10:30 a.m. Monday. “An adult like this is so efficient at hunting, he may be hungry only one hour a day.”
While a few thousand bald eagles are counted over Hawk Ridge each fall, the counters there see only about 150 to 200 golden eagles each fall. Until Monday, only 10 had been banded there since 1972, the last in 2001, said Janelle Long, executive director of Hawk Ridge Bird Observatory. Nicoletti, who has been banding raptors for more than 30 years, said he has captured and banded only about 10 golden eagles in his life.
But this eagle was destined for more than just an aluminum band on its leg. The Golden Eagle Project in Minnesota was seeking another eagle to carry one of its sophisticated transmitters. The project is a cooperative effort of Audubon Minnesota, the National Eagle Center at Wabasha, Minn., and other cooperators. As it turns out, many golden eagles winter in southeastern Minnesota and the western Wisconsin bluff country.
Four golden eagles have been fitted with transmitters since 2008, and two of those still are sending signals.
Rushed to Duluth
As soon as word spread that Nicoletti had captured the golden eagle, Mark Martell of Audubon Minnesota began driving north from the Twin Cities with a small duffel bag full of gear. He arrived in Duluth about 1:45 p.m. and began the hour-and-a-half process of rigging and fitting the eagle with its transmitter.
The untranquilized eagle was kept calm in a large cardboard tube until Martell arrived with Kristin Hall of Audubon Minnesota. While Hall gently cradled the docile bird for an hour or more, Martell and Duluth’s Dave Alexander, a bander at Hawk Ridge, worked to create a harness and attach the transmitter.
The eagle, reclining in Hall’s arms, behaved like a perfect patient, never struggling, never snapping at Martell, just blinking and staring at a dozen assembled birders with its fierce eyes. Its yellow feet, held firmly in Hall’s hand, bore talons that no rabbit would ever want to feel piercing its backside.
The eagle had buff-colored tufts of feathers atop its head and a palette of earthy browns on its back, its chest and its wings. An adult golden eagle is about 30 inches long with a wingspan of 6½ feet.
Nicoletti estimated this male to be at least 5 years old and weigh between 6 and 8 pounds. Females run larger.
Once activated, the transmitter on eagle No. 53 (named for the last two digits of the transmitter’s identification number) will record its location by GPS each hour during daylight hours. It will store the information and, every three to seven days, will upload the data to a satellite, which will send it to Martell by e-mail. He posts the locations of transmitter-equipped eagles on the Audubon Minnesota website, mn.audubon.org.
The transmitter, smaller than a deck of cards and lighter than a stick of butter, rides on the eagle’s back like a tiny backpack. The transmitter is powered by a tiny solar panel, and its life is estimated at five to seven years, Martell said.
“The goal of the study is to understand the golden eagle’s habitat use,” Scott Mehus, education director at the National Eagle Center, said in a telephone interview.
The four previously GPS-equipped golden eagles have nested in eastern Canada in Nunavut and Labrador, wintering in southeastern Minnesota and western Wisconsin.
‘Played it, caught it’
Nicoletti said he lured the eagle to a bow trap on the ground at Hawk Ridge. When a raptor lands, the trapper springs the trap, which flips a net over the bird. Banders use live, tethered pigeons or starlings to lure raptors closer.
“I was by myself,” Nicoletti said. “I saw the eagle. I played it. I caught it. I got it out of the trap. It was just me and that boy. It was a great moment.”
Hawk Ridge allows people to “adopt” raptors banded at the station as a way of raising money for the nonprofit organization. Duluth’s David and Cindy Blomberg had years ago agreed to adopt the next golden eagle at Hawk Ridge for $200, said Julie O’Connor, operations director at Hawk Ridge.
The Blombergs were among 40 well-insulated birders who gathered to see the eagle released on the raw November afternoon. They assembled at the edge of the ridge overlooking Lake Superior. Martell tossed the eagle high in the air, where it gathered itself, swooping down toward the lake.
Then, with its characteristic slow, heavy wingbeats, it flapped northeast into the gray afternoon sky as if nothing unusual had occurred.