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IVORY-BILLS  LiVE???!  ...

=> THE blog devoted to news and commentary on the most iconic bird in American ornithology, the Ivory-billed Woodpecker (IBWO)... and... sometimes other schtuff.
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Sunday, November 20, 2011

 

-- And So It Goes… --

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The latest issue of Birding Magazine from ABA includes a report from their official Checklist Committee, including the unsurprising decision that the Ivory-billed Woodpecker is not included on the current checklist, remaining instead a Code 6 bird, meaning probably or definitely extinct. The article is available in pdf form here:

http://www.aba.org/birding/v43n6p26.pdf

Meanwhile, Cornell has uploaded a wonderful piece (~11 mins.) with Chris Saker and Martjan Lammertink on the use of a man-made "double-knocker" box to research the Pale-billed Woodpecker in Costa Rica. Although this was only uploaded recently I assume the design may be the same version(?) of the box that was employed during parts of the IBWO search in the southeast:

http://tinyurl.com/7oqqzde

...would be good to know to what degree Cornell will make the boxes available to interested independent Ivory-bill searchers, or at least give out the specifications for folks who may wish to construct their own?

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Comments:
These devices are really not difficult to construct if you have a few basic tools. The basic design, which is Martjan's, is quite simple. The device consists of screws, nuts, washers, and dowels. The resonating chamber is simply a wooden box strapped to a convenient tree.
 
Acoustically the sound the DK simulator makes has some notable differences from the sounds of real DKs documented from tropical Camephilus spp. These differences are a function of the striker being two long sticks rather than one hard bill, and the resonator being a small plywood box rather than a big resounding tree. These differences are also discernable to the ear; the simulation sounding more like a "whack" and the real thing sounding more like a resonant hollow "boom." I talked about this in my blog series particularly in these two posts:

http://bbill.blogspot.com/2009/10/simulations-galore.html

http://bbill.blogspot.com/2009/10/bass-notes.html

There are also some demo videos there of the exact same DK simulator design in use in Tennessee.

Anyone who deploys these should be aware, though, that if you have more than one party in the field, and one of the groups has a DK simulator, you will worry yourselves blue in the face trying to sort out whether any putative DKs heard by the other field parties were the simulator or a real-thing response to the simulator! Those spectrographic differences between simulated and real can help you sort this out, but only if you actually got a decent recording of the "unknown" DK. Even if you think you are certain about times, locations, etc., some nagging doubt will always remain.
 
Also keep in mind that regardless of the ABA decision, the Ivorybill remains on the Federal Endangered Species List and still is fully protected as such. One of the things it is protected from is being disturbed and molested, such as by someone using a DK simulator. My understanding of this that you cannot use a DK simulator without a Federal permit in an area where Ivorybills are known to occur. At present no such places exist. But both birding ethics and federal law would dictate that, unless you are an official regulated researcher, if you ever come to feel that you have confirmed the presence of the species in an area, the DK simulators (clarinet mouthpieces, recorded playback, etc.) should be shelved.
 
It's probably worth mentioning (in case an interested searcher is not aware) that although there may be some notable differences between the wood boxes and the sounds of real, documented DKs,simulated DKs using these boxes and other artificial methods have often been close enough to the real thing to attract tropical (e.g.,Pale-billed) and temperate (Magellanic) Campephilus woodpeckers.
 
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