Saturday, September 03, 2005

Is the perched 'Ivory-bill' actually just some out-of-focus vegetation?

Ok, this is very interesting to me. In Cornell's paper, Cornell suggests that a distant black-and-white blob is an Ivory-billed Woodpecker. I've reviewed the Luneau DVD yet again, and I think that the blob is more likely to be just some out-of-focus vegetation. I'm talking specifically about the blob pictured in Figure S5, on page 9 of Cornell's Supporting Online Materials--this is supposed to be a distant Ivory-bill perched on a tree, seen on the video about 20 seconds before the "Ivory-bill" begins flying from that general area.

Here's why I say that: I carefully watched the video at 1/8 speed and kept my attention on the right side of the video (at around the 49 second mark, the bird flies from the extreme left of the screen). Over on the right side, as the video proceeds, I can see several black-and-white blobs that look very much like the "Ivory-bill" that Cornell sees on the left side. As the canoe proceeds forward, the blobs form and disappear as leaves in the foreground align with tree trunks in the background, etc.

When the tree where the "Ivory-bill" was perched was later inspected, no black-and-white mark was found. That makes sense to me--in my opinion, the black-and-white blobs on the video are not accurate views of anything on the trees themselves; rather, they are just artifacts of an unfocused camera.