Monday, February 11, 2008

Crash

I saw last night's PBS program on Horseshoe Crabs and Red Knots. It seemed to be a fairly thorough treatment of the issues and treated all sides evenly (more evenly than I would have). Most of the information was familiar to me, though I was not aware that some crabs were returned after having blood drawn for medical purposes.

One of the most striking images in the film was a side-by-side comparison between a red knot that had spent time eating horseshoe crab eggs at the Delaware Bay and another that had arrived only recently. There was a visible size difference; the recent arrival was at least a third smaller, partly because it had metabolized muscle in addition to its fat reserves. The image emphasized how important egg deposits are for migrating shorebirds. Without a sufficient food supply, there was a real question whether the leaner bird would complete the journey to its Arctic breeding grounds.

If readers have any other thoughts, please leave them in the comments.

For more on the subject, see the USFWS Red Knot page (as well as NJDEP's). There are also blogs called The Shorebird Project and Tierra del Fuego Expedition that are written by shorebird researchers.