Lakes and Ponds An abundant food source is important to great blue heron and other fish-eating birds while nesting and raising their young. During the late summer, when young alewives are coming out of ponds and lakes, young birds are learning how to fish. It is key to the young birds to practice fishing techniques and build up strength to make it through their first winter. While the Penobscot River eagle population has come a long way from its low point of the 1970s, there are still concerns. Eagles continue to establish nests, but reproduction rates are down as compared to other areas of the state. With low numbers of migratory fish currently in the river, eagles feed more heavily on ducks and other waterbirds in the winter. This means eagles are eating higher on the food chain where environmental contaminants tend to be concentrated. An indicator of what dam removal on the Penobscot may mean to eagle and other bird populations can be seen by looking at the removal of the Edwards Dam on the Kennebec River. Since the Edwards Dam was removed in 1999, flocks of immature eagles have returned, and eagle sightings have increased dramatically along with osprey and great blue heron. Eagles and osprey are known to compete for limited food resources. With the return of ample sea-run fish populations, both species will thrive along the river and throughout Penobscot Bay. Sea-run fish, which are often found to be less contaminated than freshwater fish, provide a source of food at critical times of the year for heron, merganser, eagles, osprey and other fish-eating birds and will enhance winter food supplies for birds of prey. Click here to read an eagle success story. Click here to learn more about the vast changes on the Kennebec River since removal of the Edwards Dam ten years ago. BACK