- Written by Clyde McMillan-Gamber Clyde McMillan-Gamber
Happily, bald eagle populations have increased greatly throughout North America, including in southeastern Pennsylvania, because of the ban on the use of DDT since 1972.
Additionally, bald eagle eggs from Canada have been hatched in the Lower 48; the resulting chicks are raised by humans disguised as bald eagles in nests located on towers on islands on rivers, including the Susquehanna.
Those youngsters, imprinted on islands throughout the United States, returned to them as adults to raise their own young.
Stately bald eagles today, like all owls, hawks, and eagles, are protected by laws, and people have been educated about them. And the eagles adapted well to human activities, around larger bodies of water and in farmland, to their benefit.
Bald eagles are large, elegant birds, dark as immatures but sporting white heads and tails when fully adult at 5 years old. And these common birds are easily observed “in the flesh” in the wild and on computer screens, due to live cameras.
Many bald eagles today winter along their traditional habitats of rivers and estuaries, where they prey on larger fish, coots, ducks, and other creatures. And they scavenge dead animals as well.
Winter gatherings of majestic bald eagles are enjoyed at the Mississippi Flyway in Wisconsin and Blackwater Refuge in Maryland through live cameras and computer screens.
Locally, scores of eagles winter below Conowingo Dam on the Susquehanna River in northern Maryland and Safe Harbor Dam on the Susquehanna in Lancaster County. These birds are readily seen live in the wild. And one can view online videos of bald eagles wintering at Conowingo.
Earth’s gravity, pulling water down turbines in the dams, generates electricity, and the water rushes out below the dams. That turbulence keeps those parts of the Susquehanna’s water open when the rest of the river is frozen “wall to wall.”
Fish, therefore, are available to hungry bald eagles, cormorants, gulls, herons, and other fish-catching birds all winter. It’s interesting to see these birds catching fish, whether viewed in person or online.
Many other bald eagles adapted to wintering on farmland, including in southeastern Pennsylvania, in recent years. There they ingest fish, rabbits, and other kinds of wildlife. And they scavenge dead farm animals, particularly chickens, disposed of in fields and road-killed creatures on rural roads. It’s exciting to see eagles lift off roads before approaching vehicles.
Bald eagles raise young through much of North America, including in southeastern Pennsylvania, particularly along the Susquehanna River. But other pairs nest near creeks in cropland here.
Some bald eagle pairs begin courting in November. They soar together, and perch together, in trees and on their stick cradles, high in treetops or power towers. Some of those pairs are seen live in the wild or online because of live cameras focused on their large stick nurseries.
Baby bald eagles hatch in March locally and fledge in June, when prey is abundant. Four or five years later, they are paired and ready to rear their own chicks.
The magnificent bald eagles have increased tremendously throughout North America. And today they are easily enjoyed through live cameras and computers.
Clyde McMillan-Gamber is a retired Lancaster County Parks naturalist.