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Several recent bird volumes have focussed on the importance of the 'jizz' of a bird in field identification (or if you prefer, the 'giss,' general impression of size and shape). While the emphasis on this gestalt aspect of bird identification is somewhat new, it is in fact the way most experienced birders have always ID'd the vast majority of birds seen in the field.
Next month 10's of thousands of birds will be turned in on Christmas counts with no videotape, no photographs, no field notes, no verification or validation of any kind (if you want to sign up for a Christmas count, but choose instead to watch football, drink beer, eat popcorn, and turn in a totally bogus list of counted birds, hey easy enough to do). Most of these bird IDs will occur in a matter of seconds (or less). In fact upon seeing a bird in the field, only a fraction of a second is usually needed to rule out 99+% of all known birds --- see a little brown bird hop from one bush to the next --- great blue heron, goshawk, blue jay, herring gull, sulphur-crested cockatoo, and thousands of other birds are immediately ruled out without any deep thought --- upon a second brief glance you may have it pinned down to one of 3 birds, or maybe specifically to winter wren, such is our ability to use a few glanced cues to pinpoint a species. In fact after ID'ing a bird, if asked what field marks were seen, one must often pause to bring to cognition whatever marks were involved in forming the identification, the process is so quick and unconscious for long-time birders.
Yet, in the case of the Ivory-bill, we are told experienced birders are not to be trusted. Multiple field marks must be seen and recorded, and photographs or videotape required... though it doesn't apply to 99.99% of all other birding where 'jizz' is the routine modus operandi, and is even more powerful when there are only two likely candidates for a sighting. Yes, mistakes happen, especially among novice and less experienced birders who play a significant role in Xmas counts where the data gathered is truly questionable. But do I believe that the likes of John Terres, John Dennis, Tim Gallagher, Geoff Hill, and a couple dozen others were all mistaken over the years in their claims of seeing something missing the 'jizz' of a Pileated Woodpecker, leaving but one possibility --- No. Seeing an Ivory-billed Woodpecker is not nearly as extraordinary as adamently and repeatedly discounting the observations of so many credible observers over decades is --- a kind of egocentrism or jealousy seems involved in so persistently placing one's own personal biases and speculation ahead of multiple others' onsite observations. Birds can, and most often are, ID'd by gestalt at a glance. Still, one ought not trust the accuracy of Xmas counts or lifelists, especially given that the notion of "species" itself is imprecise, somewhat arbitrary, and in flux. These are worthy of skepticism, as are most all field studies which purport to make generalizations about birds based upon inadequately small and non-random sample sizes, poor controls, ill-defined variables, and often without any replication. There is PLENTY to be skeptical of in the so-called science of ornithology. But do I accept the likelihood that some birders in the last 3 years have seen a certain single species, Ivory-billed Woodpeckers, and that still to this day the majority of potential habitat has been inadequately, indeed barely, searched? Yes, indubitably.
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