Subject: Re: ESA ?'s Date: May 8 10:31:36 1995 From: Don Baccus - donb at Rational.COM
> > I have been thinking a lot about the successes of the > Endangered Species Act lately. Specifically, I've wondered what > the overall impact of the ban on DDT is. > > Someone help me here... I thought that DDT had been banned by Executive > Order (during the Nixon administration?) and was *not* a result of the ESA. > > But isn't DDT still made by U.S. Chemical companies and sent to third world > countries who use it on all sorts of food crops that are then shipped back to > the U.S.?
> What affect does this have on neo-tropical migrants?
DDT, as far as I know, had the biggest effect on peregrine, bald eagle, and osprey populations. I would think that the most likely of those three to be severely impacted by DDT use would be peregrines, because large numbers of these birds migrate far south - there's a big peregrine migration concentration in Veracruz, far bigger than Cape May, for instance.
They face a lot of risks beyond exposure to DDT: shooting and unregulated (in practice, though not by law) falconry.
Where do most of our osprey winter? I don't know the answer to that, the raptor project I work on concentrates on accipiters. Though most accipiters which nest in the intermountain west go to Sonora and Siniloa (the spelling escapes me this Monday morning), since they're forest species exposure to DDT hasn't been sufficient to impact their ability to breed, except perhaps in very limited cases. (this is not to say there is or has been no exposure).
Of greatest concern to raptor folk right now is the rapid conversion of the pampas to agriculture. This is a goal of the Argentine government. The leading Swainson's hawk researcher in the world found some horrifying practices this past winter, with fields used by vast numbers of Swainson's hawks being indiscrimintly sprayed.
He found one field/roost with 700 dead Swainson's hawks.
On the bright side, since this is their winter range they are concentrated in a relatively small number of huge roosts, much like baldies along the skagit or in the Klamath Basin. So, in theory, protection can be had without putting an end to the conversion program by identifying and protecting specific areas used by the birds.
On the downside, it isn't clear how cooperative the government will be, nor is it clear how effectively they could force compliance anyway.
Sorry, don't know the specific pesticide being used - many are fatal to people, too if not used properly (remember the soft drink bottle spiked with paraquot (sp) used to murder a mexican field worker a few years back?)
> Roger Peffer- rpeffer at ctc.edu 509-662-1651 X2017 Z