Park protecting eagle nests

Each year since 1992, Voyageurs National Park has temporarily closed the land and water areas around active bald eagle nests to visitor use during their critical nesting periods.
The closures have been based on recommendations of bald eagle researchers from across the U.S. to land management agencies.
After the young leave the nest, which usually occurs by the middle of August, these temporarily closed park areas are re-opened for public use.
For the 2007 breeding season, 12 of the park’s 25 nesting sites occupied by breeding pairs are temporarily closed to campers and other human activities.
Four of the park’s 235 developed visitor use sites are affected by the temporary closures—Sexton Island campsite (N62) and Hamilton Island East campsite (N11) on Namakan Lake ; and Skipper Rock Island houseboat site (R45) and Sand Bay South houseboat site (R25) on Rainy Lake.
Eight undeveloped areas that visitors might use where active breeding pairs are nesting also are closed to human activity and marked with signs.
The closed undeveloped areas include East Northland Island, North Wood Duck Island Beach, West Cemetery Island Beach, West Sphunge Island Inlet,
and Richie Island on Lake Kabetogama; and East Fox Island Inlet, North Diamond Island, and Red Rock Island on Rainy Lake.
Specific management recommendations from a two-year research study on the effects of watercraft on bald eagles nesting in VNP (Wildlife Society Bulletin 2002) are being applied for the third-consecutive year.
Therefore, watercraft users—both motorized and non-motorized—must not approach on the water within 200 metres of bald eagle nesting sites and adjacent land areas during the closure period.
Boaters are encouraged to not stop on the water within the 200 metres near nesting sites.
According to Clemson University bald eagle research biologist Dr. William Bowerman, who has conducted research studies of bald eagles in the park annually since 1989, people play a very important role in protecting nesting eagles and other birds.
“May and June are particularly sensitive periods for nesting eagles,” he said. “Eagles may still be incubating eggs until late May, and if flushed off the nest for too long a period, the eggs will become cold and the embryos can die.
“Or if the adults are continuously threatened, they may abandon their nesting efforts,” he warned.
“Once hatched, it is during the first four weeks of life that the eaglets are most vulnerable,” Bowerman explained.
“During this time, eaglets are unable to regulate their body temperatures and need almost constant attention from an adult to protect them from cold winds and rain, or hot sunshine.”
On April 16, Voyageurs National Park biologists conducted the 35th-annual spring aerial survey to determine the number and location of nesting eagles.
The survey revealed 59 bald eagle nests, with 25 adult pairs observed at 25 nests. Twenty-four of the 25 breeding pairs were actively incubating eggs compared to 30 in 2006.
Due to unusually cold weather, a follow-up flight will be conducted in early May to account for possible late nesters.
Sixty-seven nests present in the late summer of 2006 were monitored this spring. Eight of 67 were gone this year either because nest trees blew down or nests fell from nest trees.
One eagle pair was observed building a new nest on an island near a former nest that existed from 1990-92. Eagles often have more than one nest in their breeding areas which are not used for nesting.
Biologists observed 24 such nests that were in good condition. Nine other inactive nests were in various states of disrepair and were not utilized.
Eagles may not tend such nests for many years, but eventually may return to the nest, refurbish, and use it for nesting again.
“Overall, we believe that reducing human presence around active bald eagle nesting sites has aided the nesting success of eagles in the park,” said park superintendent Kate Miller.
“Today there are more eagles for visitors to observe than at any time since the park was established.
“Our management goal is to help ensure the continued reproductive success and sustainability of the park’s population of bald eagles—our nation’s symbol,” Miller added.