May 30 2015
I filed a brief report yesterday on the peregrine chick banding at the Cathedral of Learning. Here’s news to fill in the gaps with a note about pronouns. I’m using the pronouns “he” and “him” though we really don’t know his sex.
Yesterday the chick’s in-hand exam showed he has no deformities but has experienced delayed development. Peregrine chicks develop so fast that biologists can age them by examining their behavior and measuring their legs and emerging feathers. Because we have a webcam we know the chick hatched on May 10 making him 19 days old on Banding Day. If we didn’t know when he hatched, his behavior and measurements say he’s 14 days old.
Here he waited and watched while the vet observed him quietly.
The vet examined his skin and feathers and found parasites (insects) under his wings and in his feathers. Insects arrive at the nest on the bodies of newly killed bird(s) that parents feed to the chicks. This transfer of insect pests happens so often to young peregrines that the banders always carry medicated powder to dust and debug the nestlings. This chick was powdered yesterday and soon, or now, is bug-free. The powder is long-lasting. He will stay bug-free even if more bugs arrive at the nest.
The chick’s mouth was examined for trichomoniasis, a parasitic infection of the mouth, throat and jaw. Fortunately he showed no sign of “trich.”
Disease and parasites consume a nestling’s energy and can delay development. Delay can also result from a less nutritious yolk, a common occurrence in the eggs of older birds (Dorothy is 16). If the yolk (food) is not nutritious, the embryo is malnourished. We don’t know if that happened here.
Delayed development made it challenging to determine his sex. At banding age, male peregrines weigh considerably less than females (2/3) so weight plus days-since-hatch indicate the sex. How old is this nestling? 19 days on camera but 14 days in-hand. Since his sex could not be determined he was given the larger size female band in case he/she grows into it.
The vet drew blood for a blood test that will take 10-14 days to complete. (I’m not a vet and have no idea what they are testing.) The preliminary result shows the chick is anemic — no surprise since parasites were sucking his blood. Now that he’s bug-free he can absorb nutrition at a much higher rate.
By the end of the exam he was sitting up and squawking — a really good sign!
With new “bling” on his legs he went back to his parents and spent lots of time sleeping off the excitement.
He’s had some challenges but he’s got great parents and stands a good chance of catching up.
- Peregrine nest area diagrams to show that this bird cannot jump/fall off the Cathedral of Learning — even if he wanted to.
- News of other peregrine nests in Pittsburgh — Neville, Downtown, Westinghouse.
(photos by Kate St. John)
p.s. Someone asked if the fluffy leg feathers (“pants”) on Dorothy are a sign of parasites. No, it’s just one of the many expressive ways birds hold their feathers. In ravens it’s a way of showing power and superiority. I don’t know what it means among peregrines.