It's been a busy week in ospreyland. I was out checking nests all day on Wednesday, trying to confirm final fledging numbers and getting those last bands read. When I got home I had a call from The Raptor Center about a chick that was ready for release after two weeks of rehab. (We believe he blew out of his nest in a storm.) After just battling thru rush hour traffic I needed to turn around and head right back to where I came from! Ahhhhhh. But after some discussion it was decided that this guy really needed to be released that evening. I always try to do what's best for the birds regardless of the inconvenience to me. This was a tricky one tho because his sibling had died, and with no chicks to care for, the parents had left the area. So we would have to release him near a nest that still had chicks and parents actively feeding them in hopes that they might adopt this juvenile. My field work that day had gathered the info we needed to decide where to release this chick, so off I went again. He flew off fine, but did not go to the nest. He landed in a nearby tree, in a somewhat awkward spot with a lot of small branches. I stayed and watched him until 8pm. The next day it was raining and my concern for this guy sent me right back there to look for him. He was not in the tree. I walked and drove all around for 5 hours, got soaked to the bone. I kept finding the resident chicks from the nest but not the newly released chick. I finally went home defeated. I had to work the next day, but one of my faithful volunteers, Barb, spent some time looking for him. She too was skunked. Today I went back again. I drove around and hiked for 4.5 hours, finding various chicks from other nests, also found a new nest being built! But my concern just kept increasing. Suddenly I saw an osprey perched on a pole and I slowly approached and was finally able to read his band and confirm that it was him!! Alive! His crop was very empty tho. He had moved away from the nest that we hoped would adopt him and was hanging around near another nest, but when he flew to the nest, he was chased off. These kinds of situations are difficult. I have seen a juvenile move to a new nest on its own and be fully adopted, cared for and fed. I recently received an email from a scientist in the U.K. asking me about this behavior. I have also been rereading some emails from my mentor Sergej about these movements of young birds between nests. Do adults recognize their own offspring? It is instinctive to chase off an intruder, but why do they allow some juveniles to take up residence? Sergej believed if the chick arrives when the parents are gone, they accept them.....but if they see the chick approaching, they will instinctively chase it. (I once observed an adult female attack her own offspring who was just learning to fly!) In this post fledging conundrum, this chick was chased off even tho one of the resident family's chicks seemed to have disappeared after fledge so how did they know this was not a missing part of their family? Ironically, the real parents of this chick were building a frustration nest nearby! But it is known that after several weeks of not caring for chicks, their parental instincts seem to turn off. Will they find each other and resume their relationship? I doubt it, but this is why we keep watching, and always taking good notes!
At any rate, after many hours of searching, I am happy that our released chick is alive. After he was chased off, I lost him again. But we will keep watching for him, to see if he is being fed somehow, since most newly fledged chicks are not able to feed themselves consistently. I always remain curious and every situation like this is different. All my time observing them just adds to my understanding of these birds. My mentor, Sergej Postupalsky, who died last year has left me a treasure trove of emails that I still refer to often. He studied these birds for over 50 years and he had the kind of knowledge that only comes from doing intensive fieldwork for many, many years. So tonight I am tired, but a bit relieved.
There are photos on my Facebook page.....for some reason this blog can't seem to access my photos
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