Hello from a long time lurker first time poster. I enjoy all the good IBWO info. on the forum. As you might have guessed I live in N. Collier Cnty. FL . I have been to Corkscrew Swamp a couple of times on boardwalk and fakahatchee a coulpe both are amazing. I am planning on visiting both over the holiday and also big cypress maybe I'll hear or see something. Corkscerw is very interesting to me because someone I am near and dear to, told me in 1998 that they had seen the biggest woodpecker they had ever seen. Back then, I asked what did it look like, answer it looked like woody woodpecker you know big and black and white with a red head. At that time I only knew of pileateds and knew nothing of IBWO except that they didn't exist and as the person who I worked with on a mostly undeveloped golf course at the time, which is less than 20 miles from Fakahatchee, told me that if you ever see a woodpecker you can't tell anyone because if you do you can't develope the property I said what kind of woodpecker do you mean he said you know woody woodpecker. So in 1998 I told this person who is near and dear to me that they don't exist and you cant ever tell anyone if you see one. I was an IDOT. I had not thought about this until I visited Highlands Hammock FL and we read about the IBWO that lived here in 69 and the person near and dear to me said, rember I told you I saw that bird, I said yeap. The next time I heard, I told you I saw that bird, was the day they announced the rediscovery. So now I 'm haunted by IBWO and very interested. The persons sighting was less than 20 km from corkscrew in a pine forest that was burned the year before. I have recently been grilling this person about it and they told me that they heard the bird almost every day, I said you mean calling thay said no banging on the trees. I wish I could go back in time. The forrest is now single family homes. Thats why I am interested. I fear the development down here, 100s of acres of pine forrest lost every day.
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Ivory-billed Woodpecker (formerly updates) (24 Viewers)
- Thread starter KC Foggin
- Start date
fangsheath
Well-known member
Florida is such a myriad of possibilities it is hard to know where to begin. I think that's one of the things that inhibits people from trying to pursue the bird there. It is worth noting that southern Florida was among the last areas in the South to get hit by industrial lumbering for cypress. That's a big part of why Corkscrew was spared - conservation had gained enough momentum by then and the pressures of war had passed. When Tanner was studying the birds in the 1930's, large tracts in southern Florida had yet to be mowed down. Big Cypress Swamp and its environs have been high on Jackson's and others' lists for a while.
It's great to have another pair of eyes and ears looking and listening for the birds. The best of luck to you.
It's great to have another pair of eyes and ears looking and listening for the birds. The best of luck to you.
Fangsheath I enjoy your posts very informative.
I recently have heard that a major developer in our area is trying to put in a large community very near corkscrew but there application with the army corp. to build a three mile canel to drain an environmentaly sensitive area was denied, we win round one.
Speaking off dead trees I drove up to orlando last week. I have never taken much notice of them before (dead trees), I was amazed at the thousands I saw just along the interstate, mostly fire and hurricane. In October I drove across alligator alley through Big Cypress I couldn"t believe how stripped bare the trees are from wilma and lots of tree damage. If IBWO's live in FL there shouldn"t be any shortage of food.
I recently have heard that a major developer in our area is trying to put in a large community very near corkscrew but there application with the army corp. to build a three mile canel to drain an environmentaly sensitive area was denied, we win round one.
Speaking off dead trees I drove up to orlando last week. I have never taken much notice of them before (dead trees), I was amazed at the thousands I saw just along the interstate, mostly fire and hurricane. In October I drove across alligator alley through Big Cypress I couldn"t believe how stripped bare the trees are from wilma and lots of tree damage. If IBWO's live in FL there shouldn"t be any shortage of food.
Goatnose
Inspired by IBW
Thanks Jesse.Jesse Gilsdorf said:
Just the other day received the book " The Ivory Billed* by J.T. Tanner and was impressed by his ability to be out there before dawn and after dusk although he did take a mid day break it seems as most of us. My "taxed comment is thus more directed to myself than anyone for I have search after dawn and before dusk not willing to put the effort into the extra equipment required to run the White in the dark. Moreover I was impressed with Tanner's ability to inquire from the loggers and the locals information, without offending or intimidating, information that steered him to high probability areas to search. The latter talent is what will save our "legs". I look forward to a sighting on the North Unit of the WRNWR so that I may move my search to the South Unit. It is so "wilderness" down there.
Jesse Gilsdorf
Well-known member
Goatnose said:
The thing I recall from WRNWR was the gas station in St. Charles. THey had a picture of an alligator gar that two men were holding on a pipe between them. The gar was probably 7 feet long. Its tail was curled on the ground. Wilderness is the word. I was surprised at the few people I saw, but given the bugs, well it was understandable.
Jesse
fangsheath
Well-known member
I have now completed synthetic beaks representing the largest published southern pileated and smallest published northern ivory-bill. With these and my previously fabricated beaks representing the averages for each species have have been gouging away in balsa wood. Here are the results for gouge width (n= 20 gouges for each data set). Five width measurements were taken on each gouge and averaged.
average pileated - mean = 2.93 mm, range = 2.44-3.40 mm
largest pileated - mean = 3.50 mm, range = 2.85-4.04 mm
smallest ivory-bill - mean = 4.20 mm, range = 3.74-4.64 mm
average ivory-bill - mean = 4.40 mm, range = 3.77-5.25 mm
From these studies I would expect some species overlap in gouge width on individual gouges, but this appears to be eliminated by measuring at least 10 gouges and averaging. To be safe I would recommend measuring 20 gouges. I understand that some people are searching for ivory-bills as far north as Illinois and Indiana (which I think is perfectly reasonable). The pileateds up there may be larger and gouge width correspondingly greater for that species. However, the wider gouges produced by ivory-bill beak are not merely due to its larger size, but especially the result of its distinctive flat-sided shape.
I reiterate that gouges consistently greater than 3.5 mm should be regarded as suspicious, those greater than 4.0 mm should be regarded as highly suspicious, particularly if accompanied by unusual sign such as scaling of very tight-barked trees or excavation of stilll-living trees.
average pileated - mean = 2.93 mm, range = 2.44-3.40 mm
largest pileated - mean = 3.50 mm, range = 2.85-4.04 mm
smallest ivory-bill - mean = 4.20 mm, range = 3.74-4.64 mm
average ivory-bill - mean = 4.40 mm, range = 3.77-5.25 mm
From these studies I would expect some species overlap in gouge width on individual gouges, but this appears to be eliminated by measuring at least 10 gouges and averaging. To be safe I would recommend measuring 20 gouges. I understand that some people are searching for ivory-bills as far north as Illinois and Indiana (which I think is perfectly reasonable). The pileateds up there may be larger and gouge width correspondingly greater for that species. However, the wider gouges produced by ivory-bill beak are not merely due to its larger size, but especially the result of its distinctive flat-sided shape.
I reiterate that gouges consistently greater than 3.5 mm should be regarded as suspicious, those greater than 4.0 mm should be regarded as highly suspicious, particularly if accompanied by unusual sign such as scaling of very tight-barked trees or excavation of stilll-living trees.
cyberthrush
Well-known member
fangsheath said:
This certainly looks to be an interesting, and potentially productive line of study, but also raises a couple of questions for me:
1. can I assume that the 20 gouges you do are using the beak at different representative angles, and that's what creates the range you end up with; or is it the case that even using the same approximate angle, the balsa wood can tear off with quite different measurements from one time to the next???
2. my only other concern/question is wondering if for any reason balsa may not yield results representative of the wild -- obviously you have no choice but to use something like it for your hand-driven attempts, but balsa is clearly very different from the woods actual IBWOs/PIWOs would be pounding into. I don't see a problem myself in the validity of the measurements, but just wondering if someone else more experienced in woodworking sees any problems comparing results in balsa vs. oak, gum, pine, whatever etc.?
BTW, fang, I'll likely quote your entire post on my blog sometime tomorrow -- if by chance you would want me to include your email address, so anyone interested could contact you about the data, let me know that (I don't usually include folks' email addresses without their permission).
fangsheath
Well-known member
First, let me make clear that these data are only intended to supplement field data on gouges, not as a guide in and of themselves. I am pursuing this work so that we can better understand how the many variables of beak morphology, technique, and excavated material interact. The real guide will be field data collected on gouges. But since these are not yet published I am presenting what I can for people for this field season.
But to answer your questions:
1) All the gouges were made using a similar technique, gouging by hand thrusting the beak straight forward with the sagittal plane more or less parallel to the edge of the wood, making as shallow a gouge as possible but still making a clear impression in the wood. Individual gouges were about 9 cm long. Much of the variation in gouge width seems to be due to variations in the texture of the wood. There is actually a surprising amount of variation in the texture of the balsa wood I am using - some of it is rather spongy and soft, other pieces are more fibrous and harder.
2) As I indicated before, there seems to be remarkably little variation in gouge width from field studies compared to my model work. I am not at liberty at present to provide field data - they aren't my data. Getting field data of my own is now my top priority - unfortunately I live outside the range of both species. I will say that while my pileated means seem to corroborate the field data quite well, my ivory-bill means seem to be a little high for some reason.
David Luneau has these data, I will send you my contact info though.
But to answer your questions:
1) All the gouges were made using a similar technique, gouging by hand thrusting the beak straight forward with the sagittal plane more or less parallel to the edge of the wood, making as shallow a gouge as possible but still making a clear impression in the wood. Individual gouges were about 9 cm long. Much of the variation in gouge width seems to be due to variations in the texture of the wood. There is actually a surprising amount of variation in the texture of the balsa wood I am using - some of it is rather spongy and soft, other pieces are more fibrous and harder.
2) As I indicated before, there seems to be remarkably little variation in gouge width from field studies compared to my model work. I am not at liberty at present to provide field data - they aren't my data. Getting field data of my own is now my top priority - unfortunately I live outside the range of both species. I will say that while my pileated means seem to corroborate the field data quite well, my ivory-bill means seem to be a little high for some reason.
David Luneau has these data, I will send you my contact info though.
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choupique1
Well-known member
naples.....
crows.... attacked the IBWO dekes in ark....... and have exhibited.... sort of rude behavior.... but i wouldn't go so far as to say a predator.......
snakes........
crows.... attacked the IBWO dekes in ark....... and have exhibited.... sort of rude behavior.... but i wouldn't go so far as to say a predator.......
snakes........
cyberthrush
Well-known member
naples said:
I think the general consensus is that adult IBWOs had no routine predators outside of Man (eggs and young were likely predated on occasion) -- in rare instances an adult might be attacked by one of the larger hawks, or Great Horned or Barred Owls, or on the ground by bobcat, but these would be at most unusual, atypical occurrences.
I found this interesting statement in the 1869 Geological Survey of Franklin County, Indiana:
"Campephilus principalis -- Ivory-billed Woodpecker. A former resident in the county. None have been seen for many years"
http://www.indiana.edu/~libgeol/cox1869/69frank3.html
Franklin County is in the Cincinnati metropolitan area. This takes the historic range farther North than is generally reported and makes Steve Sheridan's Indiana sighting seem considerably more plausible.
"Campephilus principalis -- Ivory-billed Woodpecker. A former resident in the county. None have been seen for many years"
http://www.indiana.edu/~libgeol/cox1869/69frank3.html
Franklin County is in the Cincinnati metropolitan area. This takes the historic range farther North than is generally reported and makes Steve Sheridan's Indiana sighting seem considerably more plausible.
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fangsheath
Well-known member
I believe various raptors have been cited as pileated predators, including peregrines, red-tailed hawks, and sharp-shinned hawks. Sutton apparently watched a peregrine kill a pileated in Pennsylvania. Rat snakes are certainly potential nest predators. To my knowledge there are no actual published records of natural predation on ivory-bills, either adults or young. An adult ivory-bill has some formidable weaponry, as Wilson discovered, and would be quite a match for many potential predators.
fangsheath
Well-known member
On the distribution of the ivory-bill near the northern limits of its historic range - Audubon reported it from near the mouths of the Ohio and even Missouri Rivers. Ridgway recalled seeing the bird in White County, Illinois. Multiple publications have the bird in Franklin and Monroe Counties in Indiana in the 1800's. As the forests of the Mississippi Valley between the mouths of the Ohio and White Rivers was converted to agriculture in the early 1900's, it stands to reason that any birds in that area could have been displaced up the Ohio and/or Tennessee River Valleys.
fangsheath
Well-known member
Mobbing is one of those behaviors that illicits a lot of theorizing because it seems like taking a big risk for little benefit. I don't think anyone really knows for sure why birds do it, I certainly don't. It has been argued that birds sometimes mob species that don't prey upon them, such as herons or woodpeckers, because they mistake them for predators. I think this is unlikely, particularly with very intelligent birds like corvids. I suspect that mobbing has more to do with social behavior among the mobbers than any perceived danger. The crows may be trying to impress each other more than anything else. Indeed, it has been argued that the evolution of increased intelligence is directly related to social complexity and the need to navigate one's social group. The selective advantages of enhanced social skill may greatly outweigh any risk.
Jesse Gilsdorf
Well-known member
fangsheath said:
I have never seen audobon reporting the bird near the mouth of the Missouri. I have heard of near Cairo. The mouth of the Missouri would probably be the furthest north it would ever be reported. Where did you find that reference? I certainly doubt any IBW would be that far north in Illinois today. I live north of that area on the Illinois river and there are no IBW here for sure.
Jesse
fangsheath
Well-known member
The Audubon reference comes from Jackson's book, he may be referring to this account:
http://www.abirdshome.com/Audubon/VolIV/00426.html
As you can see, in this account Audubon doesn't specifically say he saw ivory-bills near the mouth of the Missouri, but certainly he suggests that the birds were found in the Mississippi and Ohio Valleys above of the mouth of the Ohio.
http://www.abirdshome.com/Audubon/VolIV/00426.html
As you can see, in this account Audubon doesn't specifically say he saw ivory-bills near the mouth of the Missouri, but certainly he suggests that the birds were found in the Mississippi and Ohio Valleys above of the mouth of the Ohio.
fangsheath
Well-known member
I am reading that Ken Rosenberg will be a guest on NPR's "Science Friday" tomorrow at 2:00. I assume this is eastern time.
I wonder if Cornell has the time or has considered estimating the predator pop. Seems that this might be important info to gather to bring a critically endangered species back to viable pop. I would think large raptors would pose a much larger threat at this point than any hunter.
Wouldn't it be nice to have to eyes and flying ability of a raptor to help us search?
Wouldn't it be nice to have to eyes and flying ability of a raptor to help us search?
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