Saturday, January 15, 2005

A BIGGER STORY THAN PALE MALE & LOLA:

A BIGGER STORY THAN PALE MALE & LOLA:
more thoughts from John Blakeman


Yesterday I wrote John Blakeman to tell him how many readers of this website have written to say they love his letters. I told him I was thinking of writing more about the nest-removal crisis. Here's a part of his response, beautifully written as usual:



... the far greater story, with many implications, is this unforeseen invasion of an urban environment by a wild species presumed utterly un-adapted to such reproductive success. As you know, I heard of a pair of red-tails nesting in Central Park many years ago, [Note from MW: He's talking about my book here] but I utterly dismissed the story as an aberration probably equivalent to the many others we outlanders hear about New York. There couldn't be any real biology here, just some weird red-tail behavioral anomalies. Knowing the species as well as I do, none of this was out of the question, and all of it could be easily dismissed. After all, raptor biologists wouldn't anticipate going to the center of Manhattan Island to learn about the red-tail. But I was wrong on so many accounts.

The greater story is not just Pale Male and Lola, or even city red-tails in general. The big story is how wildlife can adapt to modern urban life. The Norwegian rat did that several millennia ago. Squirrels didn't have to adapt at all to urban forests. But raptors are invading cities and thriving. Falconers, having raised and trained peregrines, knew that this species could probably be enticed to breed in urban areas. That's a now well-described conservation success story. But no one, even "experts" like me, would have ever imagined that red-tails would elect to enter cities and breed there.

As a falconer and raptor biologist (and conservation lecturer -- I have several conservation slide shows that I give on raptors, prairies, Alaska, and my Western Studies) I'm always concerned when conservation and ecological success stories are so frequently neglected. Environmentally, it's not all going to hell. The good stories, such as the restoration of raptors, or my tallgrass prairies, have to be told, to give encouragement and hope. . .

Keep in touch.

Sincerely,

John A. Blakeman

Friday, January 14, 2005

A New Letter From John Blakeman About Young Hawks

A New Letter From John Blakeman About Young Hawks

Marie,

I read Lincoln's posting this morning on his website describing his sighting of another red-tail in Central Park. He recognized it as a young bird, but pondered whether it hatched in 2004 or earlier in 2003.

As a help in "aging" the red-tails now being seen ever more frequently in Central Park, I sent to Lincoln the following field marks. For those who see new red-tails visiting Central Park, here's how to determine their ages.

Birds in Their 1st Year (from fledging in Spring through the first molt in their second summer) -- These hawks look like red-tails, but don't have red tails. The tails are brown-banded, matching the brown color of the back. They also have very prominent dark belly bands, a belt of dark feathers across the abdomen. Their eyes are a dull, light yellow, never dark.

Birds in Their 2nd Year (after the second summer molt, before the completion of the third-summer molt) -- All of these will have a red tail (or a mixture of old, un-molted brown feathers flanked by new red feathers). But the eye color will vary from a slightly brown-tinged yellow to a slightly darker brown. The iris will never be completely, uniformly brown as in full adults. It wll be light-colored, but not as bright as first year birds. Yellow-eyed, red-tailed birds are always in their second year.

Birds in Their 3rd Year -- This is where it gets tricky. Third year RTs have the red tail, of course, and their eyes are dark brown, similar to fully-mature adults. But almost always the iris is darker brown at the top of eye compared to the bottom. Third year birds have a remnant hint of the immature yellow at the bottom of the eye. If you see a dark-eyed RT, but there is any variation between the darkness of upper and lower portions of the iris, it's a bird in its third year. These differences can be rather subtle, so take care.

4th Year and Older Birds -- These marvels always have uniformly dark irises. After the third year, it's very difficult to assess a bird's age. There is one field mark that we believe to be true, but don't have really good data on. Watch your birds and see if you see this phenomenon.

We see old, successful, mature adults sitting around the countryside that don't have the usual dark belly band. It appears that some, maybe most (but certainly not all) older birds tend to lose the dark feathers on the belly as they age, probably well after five years. Certainly not all adults lose the band as they age. I had a 16-year old bird who looked like she was in her fourth year.

Obviously, to properly discern iris coloration, one has to telescopically zero in on a perched bird. A pair of binoculars is often insufficient to separate third year birds from older ones. A spotting scope is best.

Hope this information is helpful.

Sincerely,

John A. Blakeman