Wednesday, June 03, 2009

From Nestlings to Fledglings

[Please note - I updated my last entry with a photo of one of the nestlings holding its foot up as I described.]

At some point in the very near future the 4 nestlings will transform into fledglings--that is, they will take their first flights. Peregrines generally fledge at about 40 days of age. For this bunch that will be on or about June 7-this weekend. While it could be sooner than later, I predict that we'll see the majority of the fledging activity occur the week of June 8.

We did have a call that someone thought that one of the birds flew yesterday. Given that we are still several days away from that 40 day "birthday" I seriously doubt that if one were to go off the ledge at this early stage it would be able to make it back. All 4 nestlings were accounted for last evening around 7 p.m. so in my professional opinion, I don't believe that any have flown yet.

It is often the males that fly first because they are smaller. The females at this stage are quite plump and likely are actually heavier than the adults. After all, they've been doing nothing but eating for the past 5+ weeks! Sure, they run up and down the ledge and flap for a little exercise but they do have a certain amount of "baby fat" (more than the smaller males) that will weigh them down and delay their takeoff.

As the birds get closer to flying you'll notice them doing a bit more practice flapping. They might even flap hard enough that they'll hover a couple of feet up over the ledge. The first flight might result from a bird simply taking off from the ledge on its own accord. Or, a first flight might occur if a nestling is too close to the edge and a strong wind gust blows it off. Another scenario altogether is a group of nestlings all scrambling for food and one is too close to the edge...

In all actuality, flying is not the hard part. It is completely natural for the birds to flap their wings and with the proper equipment (flight feathers) they can fly instinctively with little problem. The hard part is landing. The young birds will have to hone their skills of maneuvering: using their tail to steer, slowing down and most of all, learning what they can and cannot land on. Reflective windows pose one of the biggest problems because the birds will not be able to differentiate between what is a reflection of sky in a window and what is really sky. Consequently, we can expect the birds to hit windows during the first couple of days on the wing as they learn some important life lessons. The adults will still provide food for a time but it won't take long after the young master flying that they start learning to hunt for themselves.

There are several ways we confirm the status of fledging. One way is by eye witness accounts-observers that are able to see either from the street or the falconcam. The view from the falconcam does give us a window to what is going on, but it also has its limitations--areas of the ledge that are not in view and other ledges on the building we cannot see. Another way we track is by leg band reports via the falconcam. These reports are extremely important at this time to confirm which falcons are still on the ledge. Finally, we can also ascertain the status of a fledgling if/when a bird ends up on another building or somewhere else downtown where witnesses can confirm its ID by reading the leg band.

For the most part Scout and Orville will be keeping track of the young where ever they land. The Division of Wildlife will only intervene if a falcon is seriously injured or winds up in a location that it cannot get out of. Most people downtown are familiar with the falcon project and so if/when a mishap occurs we are notified. There are also interested individuals on the ground watching the birds, and Rhodes Tower Security has all the appropriate contact information for the Division of Wildlife. Hopefully, things will go well and it will not be too exciting of a week for me!

On another note, here's a short clip I captured of Scout feeding two of the female nestlings. Even though they are capable of self-feeding her instincts still dictated that she provide food to them: