Friday, August 2, 2013

Fledging...

I would like to elaborate on something mentioned earlier which seems to have raised questions. It relates to behaviors during the early post fledging time. When an osprey chick flies for the first time, they do not have the skill level that an adult has. I mentioned that if they land on the ground, they usually can't get going again from that position until they are stronger and have developed more skill. Adult ospreys do not usually feed a chick that ends up on the ground. Feeding at that stage of development occurs on the nest. If a rescuer finds a chick on the ground, they may try to place a chick on a fence or in a tree. This is done to facilitate the young birds take off, to return to the nest.(and to prevent predation by ground predators). This does not mean the chick will get fed there. In my 20 years of watching young ospreys fly for the first time, I have seen them land somewhere, like on the ground, in a tree or telephone pole and sit there food begging for many hours, perhaps even a day or more. I have NOT seen the adults feed them there. I have frequently observed the adults flying around the stuck chick with a fish, and then flying to the nest, as if to lure them back there to eat. Feeding occurs at the nest for 10- 20 days after fledge. Young ospreys do not seem to have the dexterity to perch and hold a fish to eat at first. It won't take them too long to develop those skills, but at the time of the first few flights they usually need to return to the nest to get fed. It can seem cold to see adults ignoring a young osprey desperately food begging, but perhaps they instinctively know that if the youngster can't fly well enough to get back to the nest, it is not a wise investment of their energy to feed it. Sometimes human intervention can change the outcome, but sometimes not. I have seen chicks repeatedly jump or fall out of a nest, and putting it back in the nest several times did not help. Some chicks just don't develop properly and do not survive. I always think its worth a try. This is contrary to the behaviors of some other birds. I have rescued songbirds who fledged too soon many times, placing them in a high perch and the adults will feed them there. I can't explain why ospreys behave differently, I can only report what my observations have been over 20 years.

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