The grace, strength and beauty of bald eagles has been admired through the ages. It is difficult to believe that this majestic bird, our national symbol, faced extinction just a few decades ago.
Bald eagle populations were at an all time low in the 1960's, with less than 12 known pairs on the Chippewa National Forest. Today, the Forest supports on of the highest breeding populations of bald eagles in the continental United States.
Since the banning of DDT and bald eagle management, the eagle populations on the Chippewa National Forest has been stable with 140 - 190 breeding pairs since 1991. Since then, the populations has leveled to approximately 178 nesting pairs found each year. Biologists gather information on eagles by recording the number of nesting pairs each spring, and young produced each July. The return of the bald eagle is one of America's greatest wildlife conservation success stories.
Bald Eagle Natural History
With a wingspan of seven feet, the bald eagle is the largest bird of prey in northern Minnesota. The adult eagle is easily identified by it's striking white head and tail. Eagles attain their adult plumage at four or five year of age.
Young bald eagles remain flecked with brown and white and can be mistaken for golden eagles, though golden eagles are not found in Minnesota. Eagles mate for life, and return to the same nest area each year.
Large red and white pines on the Forest make excellent eagle nesting sites although aspen and others are occasionally used. Nests sometimes reach 10 feet in diameter and weigh over 4000 pounds!
Eagles generally lay two eggs and incubation lasts about 35 days. Eagles are especially sensitive to disturbance during incubation, an important reason for people to respect nest locations. The average nesting success for Chippewa National Forest is 60%; about one-half of these fledge successfully. Eaglets remain in the nest about 10 to 12 weeks.
Bald Eagle Management
The bald eagle is federally listed as a threatened species. The bald eagle is being considered for removal from the threatened list, at which time it would be listed as a sensitive species on the Chippewa for a minimum of five years. In the state of Minnesota the bald eagle is listed as a species of "special concern". Protection of nest sites from destruction and disturbance has been a key objective of bald eagle management on National Forest lands.
Each eagle breeding area has a management plan specifically tailored to the site. Circular "buffer zones" have been established around each nest to limit human activity. Timber cutting, roads or trail use are restricted within 3330 feet of each nest. A zone of 660 feet from the nest allows activity only between October 1 to February 15, while eagles are on their winter range.
The number of active bald eagle breeding pairs appears to be leveling off on the Chippewa. Increasing competition among breeding pairs at high nesting densities and continued lake shore development may be factors affecting the Forests "carrying capacity" of bald eagles. Future monitoring strategies may be geared toward focused population sampling in areas of the Forest with varying eagle nesting densities.
Eagle Viewing
People often make a special trip to the Chippewa National Forest to observe bald eagles. The best opportunities for viewing bald eagles are from the large lakes and major rivers. Wildlife viewing is best at dawn and dusk. Tall white and red pine with openings in the limbs are often prime perch sites. Nests are usually located about 10-20 feet from the top.
Eagle nest sites are kept confidential to protect the birds from disturbance during incubation and rearing of young. If you know of an eagle nest location, please use caution and watch them only from a distance.
In the spring and summer start your eagle viewing expedition while boating at the biggest lakes such as Cass, Winnibigoshish and Leech. Watch along the shorelines for eagles perched in trees on calm days, and overhead air shows on windier days. Canoeing on the Mississippi or Big Fork Rivers almost always guarantees an eagle sighting.
You can easily reach open viewing areas at Federal Dam at Leech Lake or Winnie Dam at the east end of Lake Winibigoshish. Near Cass Lake, Knutson Dam and campground provide an expansive view of the lake and opportunities for fishing, by humans and eagles!
The Mississippi River winds along Highway 2 between Cass Lake and Deer River. Eagles are often seen soaring overhead. A prime viewing area is where the river meets the highway about eight miles west of the town of Deer River.
In autumn, eagles are often seen perched on lake or river edges, searching for food. The change in temperatures causes the lakes to "turn over" as the cooling surface water mixes with lower layers, causing fish to die. Eagles capitalize on the fish's inability to adapt to seasonal changes!
Eagles remain near open water during winter months. On the Chippewa, dams, channels between large lakes and faster moving rivers provide such habitat. The Cass Lake Wayside rest provides easy parking for those with an hour for exploring.