Wednesday, November 14, 2007

David Sibley on Ivory-bills, Science and Priorities

Hawaiian birds, left to right: Kauai O'O (extinct); Kauai Akialoa (extinct); Kauai O'u (extinct) ; Kauai Nukupu'u (extinct); Puaioho (less than 200 left); Kamao (extinct)

The great wildlife illustrator, bird man, and field-book author David Allen Sibley writes of Ivory-bills, sound science and priorities:

I have been skeptical of the Ivory-billed Woodpecker reports since about two weeks after the announcement in April 2005. This view has only become stronger over time and is based on my thorough study of the published evidence, drawing on my 35 years of experience as a birdwatcher and student of bird identification, and on my experience reviewing countless similar rare bird reports.

I find this Draft Recovery Plan fundamentally flawed, as it presumes that there is an urgent need for action based on "convincing evidence of the species' existence" when in fact no independent review finds that evidence convincing. The 2005 claim of "irrefutable proof" was incorrect; and was based on ambiguous evidence misinterpreted through hope and desire (commonly called wishful thinking). The case for the bird's continued existence rests on a few seconds of extremely blurry video (shown to be consistent with Pileated Woodpecker), a handful of fleeting glimpses by observers steeped in expectations, faint audio recordings that more or less resemble Ivory-billed sounds (among other things), and a belief that all of these possibly suggestive bits add up to a compelling body of evidence (1). None of the evidence stands up to scrutiny; there is no proof. Most importantly, hundreds of thousands of person-hours of intensive search efforts since 2005 - which could have confirmed the sight reports - have not produced any confirmation at all.

Based on such weak and ambiguous evidence, the proposal to spend up to $27.7 million of a very limited budget on efforts to find and recover the Ivory-billed Woodpecker is unsupportable. Hundreds of other species with well-documented needs would be better-served by those resources.

Sibley goes on, in the comments section, to note that while attention (and money) is being slathered on "saving" the extinct Ivory-billed woodpecker, dozens of still-living Hawaiian birds are being pushed into extinction without so much as a peep from the public:

The contrast could not be greater between the Ivory-billed fanfare and the relative silence about Hawaiian birds.

Searching the Bird Life database for critically endangered or extinct birds in North America turns up 44 species, 36 of which are Hawaiian endemics! Twenty-two of those Hawaiian birds are listed as extinct, plus Hawaiian Crow which is extinct in the wild with only a few individuals surviving in captivity.

And what is killing off those Hawaiian birds? David Sibley does not mention it, but the main forces of destruction are avian flu and avian pox borne by mosquitoes, and to a lesser extent the predation of rats, and habitat destruction caused by pigs, goats, and humans with chainsaws and development platts. Added to the equation has been some competition with other species of introduced birds.

As odd as it may sound, though Hawaii may have lost more bird species than any other spot on earth it is also home to more introduced bird species than other place on earth, thanks to efforts of a "Bird Lovers Society" (Hui Manu) that began in the 1930s.

A final tip: check out David Sibley's main web site and blog. His field guides really are the best, in my opinion.

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