"This is the time of the year that Warren County eaglets are born," according to photographer Bill Simbeck. "I was out Tuesday (March 25) afternoon and checking, did not see any chicks, but the parents are acting like they are."
Simbeck became interested in the bald eagle population in Warren County 15 years ago and keeps track of approximately 10 nests.
Simbeck spends a great deal of time in the woods with his camera, and a large part of his focus is on eagles.
"The mating season starts in mid-January, this is a mid-air courtship 'dance'. Adults grasp talons and fall together, swooping upward before they reach the ground. After the courtship the pair go to work and make repairs and add a new inner layer to the existing nest," he said.
The National Geographic Society website said the largest bald eagle nest on record was nine and a half feet wide and 20 feet high, weighing more than two tons.
"They usually lay two to three eggs from mid to late February. Once the eggs are laid, both the male and the female will alternate in covering the eggs," Simbeck said. "The incubation period is 35 days, (and) depending on when the eggs were laid they should start to hatch around the first of April."
"Eaglets weigh about three ounces when born, at three weeks about 21 ounces, at six weeks about five pounds. Their main diet is fish, (but) waterfowl and mammals have been known to be supper also," he said.
"At about six weeks they begin to transform from their gray down to dark brown features," he said. "Around early to mid-June they start to flex and exercise their wings."
"Late June or early July they will start to fly. They stay close to the nest to eat and rest. Usually by August or September they are out hunting on their own."
An eagle reaches sexual maturity at around four or five years of age. At that time, the eagle's energies become concentrated on the effort of finding a mate and raising offspring. Bald eagles mate for life, but when one dies, the survivor will not hesitate to accept a new mate, according to baldeagleinfo.com.
During breeding season, both birds protect the nest territory from other eagles and predators.
The Pennsylvania Game Commission offers tips and information on bald eagle nest etiquette: "There are few sights more thrilling than a bald eagle at its nest or in action along a shoreline. Responsibilities come with this enjoyment. As you enjoy eagles, you must ensure your presence and behavior do not have a detrimental effect on the eagles or their future use of the area.
"Eagle nests and young eagles are easily disturbed. By flushing a premature fledging, you can inadvertently cause injury or death of an eaglet that can not yet fly or defend itself. In the cold winter, energy is a very valuable commodity for eagles. Flushing eagles from a roost site or a feeding ground causes unnecessary stress and may expose the eagle to additional predators. So please keep your distance from eagle nests and roosts."
Tips include staying at least 1,000 feet from nests, speaking quietly and avoiding sudden movements, use your vehicle as cover by remaining inside while watching and respecting restricted zones, which are protected by state and federal law.
"Respect the privacy of the landowner. Don't tell everyone about a new eagle nest. It will attract people to nesting areas who will not use proper etiquette and other unnecessary attention to a nest. If you unexpectedly stumble onto an eagle nest, or hear an eagle vocalizing overhead, leave immediately and quietly," according to the Game Commission.