Sunday, December 04, 2011

-- And Back to the Pearl --

----------------------------------------------------------------


In
his somewhat trademark fashion, Mike Collins has once more re-visited some prior video footage (in this instance from the Choctawhatchee in 2007), to again discover the possible presence of Ivory-billed Woodpeckers. Read his report here:

http://www.fishcrow.com/choc19jan07.html


Per usual, the video is not of a nature/quality that would sway any skeptics nor move the debate -- it's not clear to me if Mike seriously thinks this quality of 'evidence' would alter mindsets. And it is almost embarrassing that he keeps pushing such footage on the Frontiers of Identification listserv where most participants are likely to roll their eyes at it (...at the Frontiers site it is not unusual to have a vigorous debate over the identity of a bird even when given perfectly good and clear photographs!... which Mike's frames are not).

There are, as usual, some frames I find mildly interesting, but nothing at all persuasive to my eyes overall. A nice-sounding double-knock is included in one video, though I have certain qualms with it as well, which are probably unresolvable and not worth getting into. Still, I do encourage anyone with the patience left to do so, to slowly, methodically work through the various clips for anything you can glean from them (...though it may not be much). I suspect the clips viewers might find most interesting are those labelled, "climb knock.mp4" and "jasa_movie1mp4".

For sheer perseverance, perhaps no one deserves the glory of eventually documenting the Ivory-bill any more than Mike does; plus, he has the luxury, afforded to few, of a job that allows him more consistent time and opportunity to look for the species in viable habitat. And if he is ever able to obtain video of a quality that confirms the presence of Ivory-bills in the Pearl to everyone's satisfaction, Mike will, in a flash, become one of the most celebrated, renowned birders in the long history of American ornithology (his various techniques, likely to become standard fare in graduate textbooks)… but, unless or until that happens, the verdict on his work seems, alas, far less promising...

For any who may be relatively new to the IBWO saga, and unaware of some of the history for the Pearl River area, preceding Mike's claims, here are a few older background pieces focusing mainly on David Kulivan's story or the Zeiss search that followed it in 2002 (unfortunately, so far as I can tell, the official Zeiss summary pages for their 2002 search are no longer available on the Web -- hmmm, is this because Zeiss now finds it too embarrassing to be associated with IBWO searches, or what gives???):

http://www.northlakenature.org/CurrentEvents/Ivory-BilledWoodPecker.html

http://articles.latimes.com/2000/nov/19/news/mn-54363

http://www.wildlifewatchers.org/esReports/report29.html

http://tinyurl.com/6psreko

http://www.birds.cornell.edu/Publications/Birdscope/Summer2002/ivory_bill_absent.html

...and finally, brief, general info about the Pearl River WMA here:

http://www.wlf.louisiana.gov/wma/2789

[Pearl River area pic above via Wikimedia Commons]
----------------------------------------------------------------

6 comments:

Erik Hendrickson said...

The motion of the bird in several of these clips is interesting, uncharacteristic for PIWO. What's the chances that one fellow, with a video camera mounted on kayak paddles would capture so many "interesting" flight and climbing behaviors in such a short period of time?

The clip linked from "swooping takeoff" (jasa_movie6.mp4) shows a spectacular dive (even at half speed). You can double click on the image to start, stop and replay the clip.

The clip linked from "takeoff from behind a tree trunk" (masa_movie1.mp4) I thought the most interesting. The 6th and 7th frames after the bird appears seems to show trailing white on the wing in maximum downstroke, and then, in the next frame, trailing white on the wing in the maximum extended upstroke position.

The clip linked from "between 18:01 and 18:14" (climbknock.mp4) shows really interesting "herky-jerky" motion similar to what caught Gene Sparling's attention, and similar to clips of IBW in the Cornell archives.

The clip linked from "15.23" (event1.mp4) again shows really interesting motion - a bird flying to ascend vertically a substantial distance.

All very interesting, another set of videos to go with Luneau and Geoff Hill's video.

Bill Pulliam said...

I see absolutely no reason to think these clips show anything but Pileated and Red-headed Woodpeckers. In the clip of the large bird flying from the top of a snag, the location of the white in the wings is not that easy to judge but on the downstroke at at least one point it looks like it is in the primary bases. The very deep downstroke is also characteristic of a launching Pileated; I don't know why Mike persistently claims that Pileateds don't do this when in fact it is a very typical Pileated action in all the launch videos I have scrolled through.

On the other flight sequences (the "event" clips), there's not a clear indication of where the white is most of the time. However, when that bird (no reason to think it is the same bird as the one launching from the snag) is readily visible, it appears to be flapping at 15-20 Hz, way too fast for an Ivorybill by anyone's estimation, up in the range of a Red-headed.

Judging from a sonogram, the "double knock" is indeed a knock on wood or some similar resonant object. But it is not clearly "double." When slowed down, it looks and sounds like a knock with reverberations. These latter noises happen only about 30 ms after the first knock and give some suggestion of happening in a series longer than just two. Even if it is just the two, this is drastically shorter than the interval expected for any Campephilus. Plus the dominant pitch of this knock is quite high, in comparison to Campephilus DKs or Pileated drums. I don't see any special reason to assume this sound came from the bird (Red-headed Woodpecker?) in the frame, anyway, given that it was not noted by the people present and could have come from any direction or distance.

As for loudness... if that bird were a Campephilus, and executed a DK at that distance, it would have knocked the observers socks off. I heard a Pale-billed DK from at least 500m in Mexico this spring, and it was still pretty loud. Historical accounts of Ivorybill DKs all mention their intense loudness.

In summary -- Pileateds, Red-headeds, and non-specific clunks.

Steve said...

Bill and Mike

Two bald men fighting over a comb.

cyberthrush said...

actually, I'M probably more bald than either Bill or Mike

Anonymous said...

jasa_movie2.mov and jasa_movie3.mov show a large woodpecker. Folks, it's either a PW or an IBW. I wouldn't put down his efforts here. These two clips need to be analyzed carefully. Collins is at least publishing video and that's more than almost any one else has done. And the woodpecker in those two clips is pretty darn big...

cyberthrush said...

I think David may mean movie1.mov not movie2 which is the Mexican Imperial footage...
and while I agree the bird in the clips looks "pretty darn big," as has been demonstrated in the past, size is VERY difficult to accurately judge in such clips.