--------------------------------------------------
The Ivory-bill has clearly hit the big-time of both science and pop culture, gracing the cover of Science Magazine AND being covered by CBS's '60 Minutes' all in a few months' time! Ed Bradley's '60 Minutes' piece was a nice, feel-good segment, but without much new news to pass along. (And though I enjoyed the '60 Minutes' report, I do worry just a bit if too much 'glamorization' of this bird in popular media may be deleterious in the long run, inspiring a cadre of publicity-minded searchers out there who don't necessarily have the species' best interest in mind.)
Also Mary Scott has posted 4 search reports from individual Ivory-bill seekers at her birdingAmerica.com site, which you may find of interest.
Cornell has likewise been collecting reports for the last several months, and it would be interesting to know if they intend to publish or summarize any of those at some point or are saving them for their own proprietary use?
In any event could be a few more slow news weeks ahead until more foliage drops from Southern forests and the winter search is well underway with many more searchers in the field trekking the vast areas involved.
-------------------------------------------------
4 comments:
Ivory-bill feeding sign questions:
I've read with great interest some of the search accounts quoted on Mary Scott's site, for instance, this one bye Bill Lunn, 10/7-8/05. People keep reporting feeding sign, and here is a quote:
"After the presentation I asked Martjan [Lammertink, one of the Cornell search team] a few questions, like how to distinguish on a woodpecker ravaged tree whether it had been worked by a pileated or an ivory bill. He said they are still working on this. The feeling is that the IBWO prefers trees with tighter bark. He said there may be side to side markings of the IBWO working its bill back and forth to scale the tree of its bark. By contrast the pileated prefers softer trees that have been dead longer and digs deeper into the tree."
Here's a similar statement by another searcher, Jesse Gilsdorf:
"What does IBW scaling look like? We have descriptions of cross hatching as though someone used a screwdriver on a tree. But even if we find a tree is the scaling observed what was described?"
Any idea how these conclusions are being drawn? As far as I know, nobody has observed the IBWO feeding in Arkansas, just fly-bys. The bark-stripping preference of IBWO's are described by Tanner, but I did not see specifics of the "side to side markings" or screwdriver-type markings. (Maybe I missed it.) Tanner does mention the stripping of tight bark. Since nobody has observed the IBWO's feeding in Arkansa, how can they know what the sign looks like? Am I missing something? Tanner also describes how the IBWO's do dig into heartwood sometimes, in the manner typical of a Pileated. Tanner mentions that Pileateds do strip bark as well, just less frequently than IBWO's.
As Cyberthrush has mentioned elsewhere, Tanner's quotes of IBWO feeding reports also mentions quite a quantity of fruit and nuts taken by adults. Seems like people should be watching hickories, pecans, tupelo, persimmons, and even poison ivy for activity. All of those were mentioned as foods by Tanner.
All of this is very curious. Again, am I missing something? Are some of these statements based on observations of IBWO other than those of Tanner, or of observations in Cuba, or of the Imperial Woodpecker, or of other Campephilus in the neotropics?
In response to Mr. Coin's comments I would refer you to a Bulletin circa 1911 USDA (as I recall) done by Mr. Beale in which he describes the food of American woodpeckers. I do not recall the exact name but I believe it was Food of the American Woodpeckers.
Mr. Beale's excellent work (he did many bulletins) is based on actual IBW stomach content evaluations showing even the percentage content of grubs vs. vegetable matter.
Foods of the IBW (from Mr. Beale's work and others) includes tree mast (nuts of various typses) seeds (including poison ivy), grapes appear to be a favorite of at least one observed bird. Grubs and insects are a given. One report shows them eating ants.
With regards to the cross hatching of a screw driver this I read in old reports turned in. As I recall the source was very reliable, but for the life of me I cannot attribute the source. It is in print and if I can find it again I will happily attribute.
I would note that I have spent numerous hours researching the bird, and have sought every primary source I could find. I would note that No modern author knows any thing based on personal experience if Cornell's statements are true. If they have been observing birds then they should be considered experts on the IBW.
They may be bird experts, but without actually having done scientific resarch themselves the have no special or unique knowledge. They are merely people that have seen the bird once or twice, and who have read the work of others.
In fact, Cornell puts out incorrect information. A fellow named AA Allen was a contributing editor to one comprehensive ornithogy book originally printed as I recall circa 1907 and reprinted in the 30's. This book shows the range of IBW in Indiana. Cornell states that the range was never in Indiana. But only as far north as far southern Illinois. Who is right, the Cornell Lab or its founder?
The Illinois Department of Natural Resources indicates that a bird was taken in Forest Park, near St. Louis circa 1888. For those who don't know, Forst Park is now basically dead center of St. Louis, and is where the St. Louis Zoo is located. When one couples this with the fact that Cahokia Mounds,(Illinois side of the Mississippi River -- basically no more than 10 miles east of St. Louis) has had remnants of IBW found in it it becomes quite plausible to believe the bird may range as far North as St. Louis or into Indiana.
Next -- Cornell has been evaluating "Double Raps". Is this the only sound the IBW makes are then calls. I would refer the reader to Cornell's own site to listen to the Calls of the IBW. One of them has drumming recorded. Drumming that is not double raps. If everyone is running around listening for double raps they may ignore drumming that is being done by the bird.
I make these points not to bash anyone, but because we (collectively) face a bigger problem -- ignorance. Mr. Coin asks "how these conclusions are being drawn" and I tell you honestly I draw mine from reading original sources and from what I find in the field. So far, the field work admittedly has left me with far more questions than answers. However, at this stage I am simply gathering information. I will sift through it later.
In the meantime, I am looking for objective criteria against which to evaluate anything I find. Finding that is a problem as is shown by your quote of me. We need hard evidence -- measurements of scalings, measurements of wings, feathers, DNA analysis, pictures, etc. When these items are obtained we will then, in part by deductive reasoning, in part by hard science, determine what we actually have observed.
I hope that answers Mr. Coin's question.
Thanks so much, Mr. Gilsdorf, for your comments. I actually have that book on Food of American Woodpeckers, and will take a look. It was really the cross-hatching in particular I was asking about.
Aha! I should have done more homework. Here is the screwdriver reference, it is from the Birds of North America account, the page on feeding, quoted here:
In a letter to Jim Tanner (4 Sep 1939), Herb Stoddard, who knew Ivory-billeds in his youth, described what he believed was Ivory-billed work on pines that had been killed by a hurricane in n. Florida: “The larger portion of the bark of these pines had been removed while it was still quite tightly at-tached, the evidence being left on the tree being comparable to that a man might leave who knocked off the bark with a cross hatching motion with a heavy screwdriver.”
This description fits the work Tanner described on hardwood trees in the Singer Tract and that I [Jerome Jackson, the author of the Birds of North America account] saw on pines in the mountains of e. Cuba in 1987 and 1988.
Original references for this are apparently Tanner 1942a. The Ivory-billed Woodpecker. (it must be in there and I missed it), or possibly Lamb 1957. The Ivory-billed Woodpecker in Cuba. Those are the adjacent references given by Jackson.
Jackson has a good discussion of the historical range on the Birds of North America account. They do mention Missouri, but not Indiana. I imagine there is some disagreement on the periphery of any bird's range, and they did wander.
Birder's World Forum, in
this thread
is reporting that Bobby Harrison is going to release a video of an IBWO from 2004 that has not been made public previously. It is supposed to happen at a conference on November 4 in Boston, Massachusetts. Harrison had mentioned this video in an article in the September, 2005 issue of Natural History, but I had not seen it mentioned in any other source.
Very interesting!
Post a Comment