Last weekend I enjoyed the mild, sunny weather and spent as much time as I could outside. On Sunday I went for a run along the University of Maine bike path, and ran into an acquaintance of mine, Bob Klose, who teaches at University College in Bangor and who shares an avid interest in the natural world. Whenever he sees me he has bird questions to ask or an interesting sighting to relate. This time he had an exciting bit of wildlife drama to share with me.

Several weeks ago he had spotted an otter eating a fish out on the ice of the Penobscot River near his home in Orono. Suddenly, an adult bald eagle swooped toward it. A northern river otter is a pretty substantial animal, weighing up to 30 pounds, reaching 4 feet or more in length, and sporting sharp teeth in strong jaws. Bald eagles average about 14 pounds and can only lift half their weight in flight. They do not normally prey on adults of these animals, taking small mammals, snakes, and fish instead. They will catch their own fish but often will scavenge for dead fish or carrion. They will also pirate fish from other birds such as ospreys – and, in this case, from otters.

Apparently daunted by the eagle’s 8-foot wingspan, deadly talons, and airborne advantage, the otter chose discretion as the better part of valor. Abandoning its catch, it dove beneath the water; the eagle got the fish without having to extend the effort to catch it.

What a scene. I shared it with a co-worker, who said, “Oh yeah, at my father’s camp there are a couple of bald eagles nesting on an island in the middle of the lake.”

I’ve had other people share their bald eagle sightings with me as well. The basic sentiment was one of awe and admiration, but not necessarily one of surprise. I got the feeling that bald eagle sightings – at least around here – are almost expected; it’s nowhere near as much of an event as seeing, say, a golden eagle (which has actually been sighted in Maine recently). After all, bald eagles are enjoying a pretty successful comeback.

This bird of prey has not always had it so easy, as many are well aware. When we adopted it as our national symbol in 1782, an estimated 100,000 eagles nested in the lower 48 states, according to data on the U.S. Fish and Wildlife web page.

Less than 200 years later, in 1963 fewer than 500 nesting bald eagles could be found throughout the entire 48 states. As quoted in a previous Bangor Daily News feature article, the eagle population in Maine was reduced to 28 nesting pairs by 1968.

Things slowly improved with the banning of DDT and increased environmental education and awareness. By 1990, eagle populations had risen to more than 3,000 pairs throughout the 48 states and to 123 pairs in Maine. As of 2003 there were 309 nesting pairs of eagles in Maine and more than 5,000 throughout the country.

The DDT poisoning during the 1960s and 1970s took a toll on a bird whose populations were already reduced by intentional human persecution, dating back to the first European settlers. Although the recovery of the bald eagle is a success story, habitat loss, human disturbance, environmental contamination, lead poisoning, and continuing human persecution continue to be problems, according to the Maine Department of Inland Fisheries and Wildlife.

Chris Corio, a volunteer at Fields Pond Audubon Center in Holden, can be reached at fieldspond@juno.com