Well it's that time a year when my eagles have hatched and now taken their first flight (fledge)
These are amazing birds and I learn something new each year I watch and engage in the chat room.
The live web camera will soon be turned off now that the eagles are off and out of the nest until next year when the parents return to lay more eggs and the process starts over again.
Q. How old are the eaglets when they fledge?
A. Nest departure as early as 8 weeks of age has been reported, but 11 to 13 weeks appear to be the most common ages.
The Hornby eaglets have usually fledged at 12 weeks of age. In 2009, the chick fledged at 85 days of age (the exact age reported in Doug’s book).
Q. Do bald eagle siblings fledge at the same time?
A. They fledge a few (or more) days apart, depending on hatching interval and sex.
Q. When they fledge, are the eaglets just pushed out of the nest?
A. No. While some eaglets fledge ‘prematurely’ (have a mishap when over- or underestimating distance to a branch), the majority take their first flights by choice and under their own control.
Q. Is it true that 40% of bald eaglets do not survive their first flight?
A. While this is widely reported on some websites and in some books, more recent studies (and nest cam studies) indicate that this is not the case. (See “survival”, below).
Q. Do bald eagle parents starve out the eaglets to force them to fledge?
A. No; they continue to bring food to the nest.
In 2009, Mom and Dad Hornby delivered 19 fish to the nest the day before their chick fledged.
Q. Do the eaglets try to follow the adult when they leave the nest?
A. Yes; once the eaglet has flown from the nest and landed, the parents will coax it to follow (luring it with food). The eaglets will follow the adults back to the nest and feed there until such time as they begin to feed alongside the parents; at that point, their foraging abilities improve quickly and they become less and less dependent upon their parents.
Q How long will bald eagle parents continue to feed the chicks after they fledge?
A. Studies indicate that this period varies; the average across the entire range is about six weeks.
Q. How does an eaglet learn what food items to hunt? Do eaglets learn to hunt from their parent or is this instinct?
A. The eaglet first learns to recognize foods in the nest; when it fledges and follows the parents, it learns by watching them and other eagles. It continues to learn by observation and through trial and error. The predator’s instinct to pursue prey is innate and is fine-tuned through learning and experience.
Q. How do you sex eaglets?
A. Biologists measure beaks and feet to determine sex but this method, while good, is not always accurate. Eaglets in studies are weighed and measured prior to banding and many biologists now also take blood samples to confirm sex.
A. Nest departure as early as 8 weeks of age has been reported, but 11 to 13 weeks appear to be the most common ages.
The Hornby eaglets have usually fledged at 12 weeks of age. In 2009, the chick fledged at 85 days of age (the exact age reported in Doug’s book).
Q. Do bald eagle siblings fledge at the same time?
A. They fledge a few (or more) days apart, depending on hatching interval and sex.
Q. When they fledge, are the eaglets just pushed out of the nest?
A. No. While some eaglets fledge ‘prematurely’ (have a mishap when over- or underestimating distance to a branch), the majority take their first flights by choice and under their own control.
Q. Is it true that 40% of bald eaglets do not survive their first flight?
A. While this is widely reported on some websites and in some books, more recent studies (and nest cam studies) indicate that this is not the case. (See “survival”, below).
Q. Do bald eagle parents starve out the eaglets to force them to fledge?
A. No; they continue to bring food to the nest.
In 2009, Mom and Dad Hornby delivered 19 fish to the nest the day before their chick fledged.
Q. Do the eaglets try to follow the adult when they leave the nest?
A. Yes; once the eaglet has flown from the nest and landed, the parents will coax it to follow (luring it with food). The eaglets will follow the adults back to the nest and feed there until such time as they begin to feed alongside the parents; at that point, their foraging abilities improve quickly and they become less and less dependent upon their parents.
Q How long will bald eagle parents continue to feed the chicks after they fledge?
A. Studies indicate that this period varies; the average across the entire range is about six weeks.
Q. How does an eaglet learn what food items to hunt? Do eaglets learn to hunt from their parent or is this instinct?
A. The eaglet first learns to recognize foods in the nest; when it fledges and follows the parents, it learns by watching them and other eagles. It continues to learn by observation and through trial and error. The predator’s instinct to pursue prey is innate and is fine-tuned through learning and experience.
Q. How do you sex eaglets?
A. Biologists measure beaks and feet to determine sex but this method, while good, is not always accurate. Eaglets in studies are weighed and measured prior to banding and many biologists now also take blood samples to confirm sex.
Saw something amazing yesterday; Bones and I were leaving to go to brunch and I looked up and saw an eagle with its baby fledging above us. I asked Bones to run back to the condo to get my camera, but he said they would be gone by the time he returned. I was so disappointed as I wanted the picture for you :(
ReplyDeleteSorry I couldn't get more pictures of eagles for you in Alaska. I saw them in trees several times but all you could make out is the white golf ball size head. I did see two in captivity. One was missing a wing and the other was blind.
ReplyDeleteAh, you're an empty nester again! And sexing eaglets? Boss, boss, boss! :-)
ReplyDelete