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Ivory-billed Woodpecker (formerly updates) (1 Viewer)

timeshadowed

Time is a Shadow
Besides, we are not talking about an extremelly remote area of huge jungle... this is the USA, with hundreds, maybe thousands of people looking after this bird every single day!

There are not "hundreds, maybe thousands" of people looking for the IBWO on private land. The land owners may be aware that the IBWO is present there, BUT THEY AINT TALK'IN.
That is the difference. And these "hundreds, maybe thousands" of people that visit public land . . .well that is exactly WHY the IBWO is not there!
 

Aracari

Birding in Brazil
Where did you get this from? Better have a look at the map and aerials again. This is VERY remote area generally described as swamp and bottomlands. Go back and read some of the descriptions. These birders are tripping over more snakes and gators than other people!

I'm sorry but that's VERY remote only in a rural or urbanized setting. How many days one need to get into prime habitat? That's not even close to other truly remote areas where great bird rediscoveries were and are being made. The whole area is what, maybe 80 miles long to 5 or 6 miles wide on average? With several roads crossing it as well as canals, which facilitates to some extent the explorations.

Ok, so I exagerated on the number of people looking for the bird (I didn't mean only people looking exclusively for this bird, but anyway)... even then, the area is being pretty well searched over and over again by experienced birders WITH capable recording equipment. And yet, no one of them doccumented this big bird.

Either these birds are incredibly wary or there's a political interest behind all that.
 

John Mariani

Well-known member
I'm sorry but that's VERY remote only in a rural or urbanized setting. How many days one need to get into prime habitat? That's not even close to other truly remote areas where great bird rediscoveries were and are being made. The whole area is what, maybe 80 miles long to 5 or 6 miles wide on average? With several roads crossing it as well as canals, which facilitates to some extent the explorations.

Ok, so I exagerated on the number of people looking for the bird (I didn't mean only people looking exclusively for this bird, but anyway)... even then, the area is being pretty well searched over and over again by experienced birders WITH capable recording equipment. And yet, no one of them doccumented this big bird.

Either these birds are incredibly wary or there's a political interest behind all that.

Well there is remote and then there's REMOTE. You are right in the sense that there are no vast wildernesses left in the American south - look at any map and you'll see roads connecting everywhere. I think when we talk about remoteness in relation to southern bottomland forest we are really talking about difficulty of access more than distance from civilization. Because the terrain is either submerged or covered in dense vegetation some areas are very hard to get into - there are large tracts here in southeast Texas, for example, that are not very far from paved roads in the sense of actual mileage, but finding a way in (and out again) is challenging. Especially with hurricane damage and a lot of downed trees...under those conditions a riverbottom forest 2-3 miles wide becomes an almost impenetrable wilderness. You are right, however, that all of these blocks of habitat are bisected or bound by roads, navigable waterways, powerline cuts, etc.

I think it likely that any IBWOs inhabiting such an area would eventually appear in an edge situation, but some claim they are exceptionally wary, avoid all people (except maybe a few hunters) and stay deep in the forest.

Interestingly, the "Big Woods" area in Arkansas has a lot of habitat that is relatively remote (meaning difficult of access), but the original sightings were all quite close to a highway...
 

Aracari

Birding in Brazil
I see, I get it now...

I also feel the same as in someday a bird would have to appear near the edge of the forest, in some rural property, a dock or something like that. Specially considering that the whole area is quite narrow (5 or 6 miles average) and I would suppose that if there was a population, the birds would probably fly up and down that area.

Well, I don't know details of the IBWO biology, but judging from other large woodpckers, I think they would eventually appear here and there, specially with teams looking out specifically for it. These are birds that move around!
 
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timeshadowed

Time is a Shadow
I see, I get it now...
I think they would eventually appear here and there, specially with teams looking out specifically for it. These are birds that move around!

But you forgot one thing . . .

When they DO appear briefly in populated areas, the sightings are promply dismissed as PIWO because IBWO's are extinct!
 

Aracari

Birding in Brazil
When they DO appear briefly in populated areas, the sightings are promply dismissed as PIWO because IBWO's are extinct!

And will continue to be until some conclusive proof appears. All we have are rumors.

Not even a blurry pic in all those several months of search...
Don't get me wrong, I DO want this bird to be alive, was very excited with it when I first heard... but the likeliness of it is fading away.
 

Bonsaibirder

http://mobro.co/saddinall
Just a quickie - I may have said exactly what I thought of LolaGal's sightings/claims but I do hope she wasn't banned for being stringy.

I'm sure we've all made the occasional stringy observation in our time!!

Cheers,
 

Frenchy

Well-known member
Has any one worked out what the population of IBWO has to be to be a self-sustaining population? I'd be really interested to know what the current theoretical population has to be to provide us with these sightings. Sorry if this has been explained before, but at nearly 11,000 postings on this thread, you'll have to forgive me for not checking too thoroughly.
 

Mike Johnston

Well-known member
More from Mike Collins, from 5.15.07 (http://www.fishcrow.com/winter07.html). Watch that space!

There's still a long way to go this search season. I have an exciting new idea and will be getting help implementing it. I'm confident that the idea will eventually lead to sightings, good videos, and possibly to the locations of feeding areas and roost and nest cavities. For now, I can't give out any details as to who, what, where, or when. This isn't just idle boasting. In fact, it's not boasting at all. It's just a positive attitude and a matter of expressing what I know can and will be done. Before returning to the Pearl, I guaranteed that I would find the ivorybills, and I delivered. While others are sitting around ignoring the evidence and being naysayers, I'm out in the field getting the job done. I have obtained videos in two states. Who else has done that? There will be more to come. Guaranteed.
 

deborah4

Well-known member
... I do hope she wasn't banned for being stringy.

Me too ... she sent me a very friendly PM requesting one of my drawings to use as a Screensaver, I replied that it was fine and asked her to send me a photo of an IBWO for me to use as my Screensaver ... doesn't look like I'll get one now :-C
 

Andy Bright

Administrator
Staff member
England
Please do not speculate on a members departure, as you have no idea of the reasons or have all the facts at hand.

If we banned members for stringy reports, we'd be left with very few members.

What we do take seriously is a member editing out (or attempting to) all their previous posts to paint a different picture.
Back on topic, please.
Andy
 

Ilya Maclean

charlatan
Has any one worked out what the population of IBWO has to be to be a self-sustaining population? I'd be really interested to know what the current theoretical population has to be to provide us with these sightings. Sorry if this has been explained before, but at nearly 11,000 postings on this thread, you'll have to forgive me for not checking too thoroughly.

Difficult to assess as calculation of MVP (minimum viable population) depends on knowledge of survival and reproductive rates (mean and variability), strength of Allee effect and proneness to inbreeding depression, none of which we have data for. With human intervention to enhance survival and reproductive success (as done for Kakapo in NZ), population can recover with a very small number of individuals.

Evidence aside and given a slim possibility that IBWOs do persist, those that do would almost certainly be the last few individuals of a non-sustaining population. IBWOs are quite long-lived (15-20 years), so I guess it would be theoretically possible for a population of c 50 inter-breeding individuals in the early 1900s to have reproduced a few times to produce one or two remaining individuals even if mortaility is far in excess of reproductive success.
 

emupilot

Well-known member
Has any one worked out what the population of IBWO has to be to be a self-sustaining population? I'd be really interested to know what the current theoretical population has to be to provide us with these sightings. Sorry if this has been explained before, but at nearly 11,000 postings on this thread, you'll have to forgive me for not checking too thoroughly.

If reports are to be believed (and we'll assume that for the point of your question), pairs have been seen and/or heard together in Arkansas, Louisiana, and Florida. At least they would appear to be finding each other. Stochastic events and inbreeding can make low populations unsustainable, but the relatively long lifespan of Ivory-bills (15 years or so) helps even out the stochastic issues. Inbreeding problems are anyone's guess - it could be like the Laysan Duck (all descended from one female without problems) or the Hawaiian Crow (existing only in captivity and with frequent birth defects).
 

dacol

Well-known member
I sure hoped for the IBWO to be alive, but after so many searches and not a single photo or video, I became a non-believer. A lot of people claim of having seeying it, yet not a single one of them managed a proof doccumentation.

So Araçari, do you think that the Kinglet Calyptura of SE Brazil still exists?
More people have seen the IBWO than the Calyptura and there are no photos or videos of the Calyptura and yet it is assumed to be extant... Interesting.

Dalcio
 

curunir

Well-known member
If reports are to be believed (and we'll assume that for the point of your question), pairs have been seen and/or heard together in Arkansas, Louisiana, and Florida. At least they would appear to be finding each other. Stochastic events and inbreeding can make low populations unsustainable, but the relatively long lifespan of Ivory-bills (15 years or so) helps even out the stochastic issues. Inbreeding problems are anyone's guess - it could be like the Laysan Duck (all descended from one female without problems) or the Hawaiian Crow (existing only in captivity and with frequent birth defects).
How does anybody know there are no problems? Won't it take a few hundred generations or at least ten generations to find out?
 

griffin

Well-known member
on Hill's website is this:



My master’s students, Brian Rolek and Rusty Ligon, will be studying foraging behavior and habitat use by Ivory-billed Woodpeckers. See the Auburn and Windsor Ivorybill web pages for a detailed account of evidence gathered in 2005/6.

I wonder how the Masters is coming on...? I bet they've widened their remit by now...


Tim

I would imagine that the Masters students are doing a Litt review of previous research and historical observations on Ivory-bills with a view to refining the current research methodology...............maybe !

You will be amazed what you 'can't do' for a Masters these days.


Linz
 

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