.comment-link {margin-left:.6em;}

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.

Web ivorybills.blogspot.com

"....The truth is out there."

-- Dr. Jerome Jackson, 2002 (... & Agent Fox Mulder)

“There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.”

-- Hamlet

"All truth passes through 3 stages: First it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident."

-- Arthur Schopenhauer

Monday, February 08, 2016


-- Intermission --


One quick 'housekeeping' note:
I don't mind anonymous or pseudonymous commenters, but would prefer if folks adopted a consistent identifying sign-off (fake name, initials, whatever), just so we can keep track of which anonymous comments hang together from the same individual, and which are new/different commenters.
But otherwise continue the comment discussions below, and meanwhile, enjoy a video:


Below are ALL the article/paper results (not cherry picked)for foraging by woodpeckers I could find in one hour. (look at the two or more posts on this site eventually).

After thousands of observations by many researchers there seemed to be very few instances where woodpeckers foraged in the lower bole. Studies found that woodpeckers of various species preferred higher areas. The Pileated was noted on the ground, mainly on logs and stumps.

The IB has a significant bark scaling advantage in the early succession of tree decay. Initial dead wood input for the great majority of deep forest trees occurs in the their branches or crown damaged by weather, winds, birds and insects.

Raw wood and the cambium in the damaged canopy is directly exposed; multiple beetle species have easy access to the exact tree layer they prefer.

At this time the lower trunk is often in excellent shape with bark and no insects. It can take years before the lower bole even has any colepteran food for IBs.

There are ecological contexts where tree decay can start lower(beaver, lightning damage) or the decay points can be multiple when caused by catastophic inputs (fires, droughts, hurricanes).

If IBs are in area with limited deadwood or when confined only to lower boles they may be forced to forage there.

A catastophic input resulting in significant area of concentrated dead wood can yield a significant density of beetle larvae due to the compounding of generations. Optimal foraging theory backed up by historical Ivory-billed literature points to this being a scenario where predation risk per caloric gain is geatly reduced and IBs can scale lower boles.

Recent searchers did not mention these types of ecological conditions to explain their strong but nonempirical assertion that IBs use the lower bole.

Abstract. – Ecological differentiation arising from morphological and behavioral differences, together with social dominance, is known to promote niche differentiation between sexes in birds. The absence of competing species would favor intersexual differences. The Magellanic Woodpecker (Campephilus magellanicus) is the only large woodpecker in the southern beech Nothofagus forests of Patagonia, with no competitors. Sexual divergence in morphology had been documented by preliminary research, and differences in foraging behavior were proposed as a correlate. Our aims are to analyze intersexual divergence in morphology and to investigate whether the behavioral differences exist. We obtained morphological data from ornithological collections and foraging records from populations from Argentine Patagonia. We estimated foraging niche breadth and the overlap of foraging variables. Adult males were larger and had bills 12.4% longer than those of females. Both sexes foraged mostly on living trees, but males foraged on larger substrates (trunks) at intermediate heights (5–10 m), while females foraged higher within the crown (> 15 m) on smaller substrates (branches). The rate of captured prey was similar between sexes (0.28 prey/min), but males consumed larger prey (wood-boring larvae) than females (near-surface prey). Social dominance by males was recorded. Based on analysis of niche breadth, females were more generalist than males in microhabitat use and body posture when foraging. Sexual dimorphism in body and bill size seems to be in line with specialization in the use of different substrates between the sexes, which is probably reinforced by male dominance. Lack of interspecific competition in this biome probably contributed to the differentiation observed between sexes. Accepted 23 December 2012.

Thanks IBWO Researcher
More studies


Although males and females foraged at the same height (F = 4.7, P > 0.50) and canopy location (F = 2.9, P > 0.80), males foraged higher than females relative to the height of the tree (F = 6.8, P < 0.01). Foraging height for the sexes combined differed among study areas, and birds foraged higher at TR than at SFRFS (Table 1; Scheff6s test, P < 0.05). When foraging heights were standardized relative to total tree height, differences between study areas were not significant (Scheff6's test, P > 0.05). Birds generally foraged about two-thirds up the height of trees (Table 1). Similarly, birds foraged in the same general location within the tree canopy (40-70% of the distance from the center to the edge of the tree canopy; Table 1). Thus, the relative height and position of foraging corresponded to the location of small and medium branches, the two most frequently used substrates.

The use of larger trees may be a function of the availability of suitable substrates. Larger trees generally have a greater volume of branches that exhibit signs of decadence in the form of dead or dying branches. I agree with Miller and Back (1972) and Jenkins (1979), who found that Nuttall's Woodpeckers generally foraged on the surface or shallow subsurface of bark. The place and methods of foraging are not surprising given that most foraging was done on small-medium branches, and prey could not be buried too deeply. Drilling and extensive excavations to uncover prey in the cambium occurred only rarely. I conclude that the use of particular tree species was influenced by the availability of food, and the use of large trees was influenced by both food availability and the presence of suitable foraging substrates.


There were only a few observations of woodpeckers feeding on dead limbs lying on the ground or feeding on agave and these observations were not included in these analyses. While males and females did not differ in their use of foraging sites during the first seasonal period (Fig. 2)) during the second period females foraged significantly more in the crowns than did males (x2 = 5.018, P < 0.05, N = 35). The seasonal shift shown by females is significant (x * = 15.996, P < 0.0005, N = 65), and while that shown by males is not significant, a similar trend toward foraging more in the crown is apparent.

thanks IB researcher

DISCUSSION Pileated Woodpeckers spend much foraging time pecking and excavating insect adults and pupae from logs and stumps. Kilham (1976) observed Pileated Woodpeckers foraging on logs and stumps in 76% of his foraging observations. In Oregon, Bull and Meslow (1977) reported that 42% and 14% of the observed Pileated Woodpecker foraging sites were on logs and stumps, respectively. Mannan (1984) reported 96% of foraging observations were of birds using dead wood, and logs served as substrates 36% of the time. Mannan also reported Pileated Woodpeckers foraged on log and stump debris in 70- to lOO-year-old timber that had undergone a selective cut. Bull (1987) observed 36% of the foraging substrates used by Pileated Woodpeckers were dead and down trees, and in total, 65% of Pileated Woodpecker foraging observations were of birds on dead wood, either snags or logs (Bull 1987). Eighty-two percent of the log-foraging observations were of birds excavating into logs >25 cm in diameter (Bull 1987). Bull speculated that larger dead wood had higher densities of wood-boring insects because of its greater surface area and greater moisture retention characteristics. Logs and stumps provide substrates for many wood-boring and channelizing invertebrates. Several workers have noted the prevalence and abundance of insects in dead and down woody material. Fager (1968) reported that in an oakash-sycamore woodland, logs at least 7.5 cm in diameter and 70 cm long contained as many as 1,7 15 individuals/log and 62 species of invertebrates. Swift et al. (1984) detected signs of invertebrate activity in 60% of approximately 1,000 logs in an oak-beech woodland. Pine stumps about 15 cm tall and 1 O-35 cm in diameter contained 939-5,678 invertebrates (Wallace 1953). Ausmus (1977) reported densities of colonizing or channelizing invertebrates of 10 to 136 individuals/cm3 in logs of a Tennessee hardwood forest. Swift et al. (1984) speculated larger branches showed more signs of invertebrate activity than smaller branches not only because they were bigger, but also because they decayed slower and probably remained on the forest floor longer than smaller branches. Our results show Pileated Woodpecker territory size was inversely related to log and stump volume, and canopy cover within territories. We believe log and stump volume is a good indicator


Differences in the foraging heights were statistically significant, with
the males foraging higher than the females. These differences were more
apparent when the sexes were feeding together in the same tree. Males of
M. superciliuris are larger and presumably dominant to the females.
Accordingly, the male should use this presumed advantage (dominance)
when feeding together to forage in the more productive portions of the
tree with the females giving way and feeding in the less desirable
areas. On Grand Cayman, the more productive sites were the inner and
outer branches where fruits, bromeliads, and many dead branches were
located. The trunk (lower portions) was suboptimal in this respect.

With the exception of the lower trunk, there were no statistically
significant differences in the use of the zones, although females used
the upper trunk and inner branches more than the males.

In Hispaniola, Wallace (1974) found greater sexual differences in
foraging in the dry winter months, considered to be a time of low food
abundance. Less sexual difference in foraging mode was found in this
species in ecologically more complex areas.
Throughout its geographic range, the black-backed woodpecker (Picoides arcticus) is rare and appears very similar in its foraging ecology to 2 broadly sympatric congeners, the three-toed (P. tridactylus) and hairy woodpecker (P. villosus). The purposes of our study were to test for differences in foraging ecology of the black-backed, three-toed, and hairy woodpeckers following a stand-replacement fire and to evaluate the importance of such fires to the viability of populations of the black-backed woodpecker. In boreal forests of Interior Alaska, endemic population densities of three-toed woodpeckers are low (<0.1/ha), and black-backed woodpeckers are extremely rare. Following the Rosie Creek fire near Fairbanks, Alaska, in June 1983, both species increased markedly. Densities of both species briefly exceeded 0.2/ha and remained high in a 67-ha plot at the edge of the burn during the following 2 years. By December 1986, densities had declined to <0.1/ha. Black-backed woodpeckers fed primarily on charred portions of moderately to heavily burnt spruces and almost exclusively by excavating larval wood-boring beetles (Cerambycidae). Three-toed woodpeckers fed on less-burnt spruces and foraged in and immediately under the bark; bark beetle (Scolytidae) larvae predominated in their diet. In contrast to earlier studies, our results demonstrate substantive differences in foraging sites, behavior, and diet of these 2 species. Foraging ecology of male hairy woodpeckers and black-backed woodpeckers, particularly females, was similar. In all 3 species, particularly the hairy woodpecker, females fed lower on trees and were far less numerous than males in the study area, which suggested intersexual displacement from foraging sites and habitats selected by males. In summer 1985, following initial adult emergence of the 1983 cerambycid and scolytid cohorts, woodpeckers declined markedly and were absent by late spring 1986. Our results suggest the black-backed woodpecker is extremely specialized in its foraging niche, exploiting outbreaks of wood-boring beetles in dying conifers for only 2-3 years after fires. Consequently, this species may be particularly vulnerable to local and regional extinction as fire suppression intensifies and programs of intensive salvage logging are pursued following fires.

There is a general misconception that when predation risks are assumed to be very small they can be ignored by the animal (and evidently by humans in the field looking for them).

In other words they think there is no behavioral response or adjustment in food foraging strategies by woodpeckers due to predation. It's an error in critical thinking and it misses the point since the magnitude of predation in not important as a threshold. What matters is that it changes behavior even when pressure is very small. There is a preponderance of examples where animals significantly change their behavior in response to the miniscule chance of predation.

A quick example is a flock of thousands shorebirds whose optimal foraging strategy is to spread out widely on a mudflat to feed. Their risk of predation from one 10 inch long merlin could by 1/5000, a small chance of death or injury. They crowd in on the flat foraging in a long string of exact spots where a con-specific just gleaned reducing foraging efficiency but the results of flocking on the mud and in the air further reduces the chances of a predator killing/injuring them. Mixed species flocks in the tropics show a similar response to predation pressures.

In fact most wild animals observed in the field backed up with experimental data for some animals, shows that they assume there is a predator around every "curve". Assuming there are no predators around the tree bole is a great thing to do?

By the way there can be many immature and wintering accipters/buteos in SE woods that can severely injure a bird. Predators do not always strike what you think is their usual prey; some birds are hungry, some make mistakes . The context of predation must be inclusive of potential injury since it all influences cognitive ecology and predation avoidance behavior.

The other thing some searchers seem to miss is the mathematical compounding of calculating the risk of performing, a common very low risk act, over and over, during the entire lifetime of an animal. Foraging is a common behavior.

They may be defeating their own point. Their belief may be that the lower bole is an oasis of IB resources. This should lead to a greater incidence of foraging there and unfortunately a greater incidence of predation events on lower boles. This would lead to IBs as a species quickly experiencing the pressure as predators realized they spend a disproportionately greater time there; predators in general exhibit more plasticity than foragers.

thanks IB researcher
I had the wonderful pleasure of observing a small group of Magellanic Woodpeckers for 30 minutes while they were foraging 2 to 4 meters from the ground in a dense old growth forest in Patagonia in 2008.

It was exciting to capture photos of them, from ground level, using a Canon 100-400mm lens, which I posted to Flickr at this link:


I distinctly recall one of the female birds flying to a branch positioned right above my companion and I to check us out as we first entered the area. She stared down at us for a moment from about 6 meters, gave out a call, and then returned to the nearby group to resume foraging. Amazing birds!
See also, https://www.flickr.com/photos/101187268@N08/24916459931/
Are you saying that this is some strong evidence that ivory bills are likely also foraging low? I am sure some reasearches can figure out why Magellanic woodpeckers are not a good corollary to help us figure out where ivory bills are most likely foraging.

That's what the conversation is about.

Magellanic woodpeckers have no competing large woodpecker species. Their foraging is well known to be more of a hybridization between what pileateds and canopy scalers likely do. In the colder forests of Patagonia they are well known to forage on prone dead wood due to a partially open niche.

Look at their plumage ---it's more like that of a pileated than not. The 3 northern Camphephilus have large white patches that may be an adaptation to blend into the dappled background of what a predator sees as it looks up at the northern "ivorybills". Pileateds and Magelanics are dark bodied; this may be and adaptation for thermal regulation but it also maybe and adaptation for being less conspicuous while feeding on the ground.

Beavers have been introduced to southern South America and Magellanic have been observed feeding low in these areas. Magellanics are also quite a bit lighter than ivory bills meaning they are more able to escape ambush predators quickly than ivory bills.

Predator pressures and there complexity are quite different between these cogeners....and when was the last time Magellanics suffered through a range wide target practice session that lasted for decades?

Most of these things have been mentioned already.

Your antidote about Magellanics approaching you fits the literature...nothing unknown to all of us. This is their response to predators or animals entering their territory. Surely you do not think this is what IBs do in the US.

As mentioned prior to your post niches determine where birds forage, direct foraging competitors (or lack of for Magellanic) predation pressure, and size. The Magellanic is quite a different animal than IB ; so is its foraging ecology.

IB researcher

I'm not necessarily arguing with you Fred. I see value in being open to many possibilities regarding Ivorybills since so much is unknown about the species' behavior. I also enjoy honoring the Ivorybill's extant relatives as a source of joy to counter the sadness of what we've lost. If your speculation as to what's what leads someone to document Ivorybills, well then, hats off to you, and hallelujah.

----The failure is STUNNING!-----Cyber 2016

i know-----lets all have an open mind.

and we will hold hands..............

Picture chasers are Master Inventors. They create an excuse for every failure.

Success is the ability to go from failure to failure without losing your enthusiasm.

If your great idea you knew would fail does-----Is it a success?


So... Where have you guided others to that they heard and saw things for which the simplest explanation was IBWO? I have. In fact, I count several scientists with impeccable biological/scientific/birding credentials among my friends these days, because I've taken them into these core areas.

You denigrate the sincere efforts of those you refer to as picture chasers. How do you think the effort to document IBWO should be conducted? Whacking on hollow trees, willy nilly with a couple of dowels and calling them "survey points" when none of the locations were more than a couple of hundred yards from the truck? Stretching a monster mist net across a choke point hoping that an IB will fly into it while every other bird that flies into it screams bloody murder?

Mark, at least, is intellectually honest enough to acknowledge a flawed hypothesis, and to try to correct those flaws. I'm just a road and bridge builder. I don't have a fancy sheepskin decorating my wall, most of what I think I know comes from a lifetimes worth of spending time in nature.

The argument about high branch versus bole stripping if bark is ludicrous. A highly respected ornithologist once admonished me to always remember that ivorybills are just birds. They want to eat, nest, and make baby ivorybills. Just like any other animal, they forage where they are likely to find food.

It really is a shame that being unable to find locations where ivorybills may be present, and lacking the ability to develop, test, and modify a hypothesis you resort to strawman arguments and ad hominem attacks on those who have these abilities.

At one time, I thought we were on the same side, I now see that isn't so. At the end of the day, success in science seldom comes from a major breakthrough, but rather, incremental revisions and additions to the body of knowledge.

Bless your heart...
I have given multiple ecological examples and hypotheticals where I think ivory bills will forage in the lower bole. If you have some data or opinion on why they are there disproportionally more than the relative ratio of bark there than from 5 feet up in a dying tree I am open minded to hearing about it.

From your latest comments I see you are dismissive of predation as an influencing factor on where Ibs may forage in a tree but there are no useful details.

So you are stating there is no predation concerns that have influenced IB foraging strategy.

Also do you have any comments on the two northern Ibs known trunk foraging behavior of zig zagging up trunks. Why did this energy consuming movement pattern evolve ?

Tks IB searcher

I have given multiple ecological examples and hypotheticals where I think ivory bills will forage in the lower bole. If you have some data or opinion on why they are there disproportionally more than the relative ratio of bark there than from 5 feet up in a dying tree I am open minded to hearing about it.

From your latest comments I see you are dismissive of predation as an influencing factor on where Ibs may forage in a tree but there are no useful details.

So you are stating there is no predation concerns that have influenced IB foraging strategy concerning the bole subject.

Also do you have any comments on the two northern Ibs known trunk foraging behavior of zig zagging up trunks. They also rotate back and forth when in the same central point; their head repositioning as if on alert.

Why did this energy consuming movement pattern evolve ?

Tks IB searcher

Don't put words in my mouth little man... You persist in making sense - free random noise... I'm through. Don't show up in my driveway again...
Col. Wolf Kurtz was upset when his exgirlfriend complained he was getting a bit chunky. She said lighten' up!

He then went up the Red River in his boat and went beserk when his methods were found to be unsound.

Hello, This may be pertient to the discussion.

Elchuk and Wiebe 2002, Wilson Bulletin concluded that predation considerations influenced where N. Flickers foraged despite food density (they foraged in areas with lower risk of predation desite there being better foraging areas). See FOOD AND PREDATION RISK AS FACTORS RELATED TO FORAGING LOCATION N FLICKERS 2002

Need link to complete article.


Thanks John
Mark M said

---I apologize. Tanner's statement was idiotic, given his own observations, as well as Kuhn's and Allen and Kellogg's, (on foraging low).

Your ~30' rule is arbitrary and seems to be based on an idea about rapid evolution that you've concocted and for which there's not a shred of evidence; in fact, the evidence is against it. It's indisputable that ivorybills fed on or near the ground in both of the last two locations where they were studied. The Cuban species did likewise.---

And Michaels again..

---but I think your ideas about scaling and 30' are utterly arbitrary and ludicrous (especially in light of what's documented from the 1920s and '30s) just like Tanner's idiotic statement about sightings near the ground, but so be it.---
- --- --- -- -

Michaels is being misleading just to try and win a point; this incrementally hurts our understanding of IBs and search efforts.The few searchers left and any future researchers deserve truthful discourse, specifics and critical thinking.Liberally and incorrectly drawing strong foraging rules or inferences can lead to poorly designed or overly simplistic methods and assumptions.

Comparing burned over, sparsely stemmed pine flats (Florida) and early seral, second growth Cuban forest possessing small DBH trees where IBs were noted foraging on or near the ground to the pertinent ecological context of a mature LA hardwood bottom is misleading. In these anecdotes of ~ 85 years ago presented by Mark as strong evidence of modern low bole foraging it's not by chance that these birds were ALL shot or soon HAD ABANDONED these subpar locations.

The somewhat habituated pair (Singer) supporting the needs of nestlings may lead IBs to lower foraging in some habitat situations. And lets not forget that there was a photo blind constructed and placed high near the nest tree that could have influenced them to forage a bit lower than average (the IBs tapes certainly are of almost always agitated birds).

Again its wrong to be misleading; hopefully its not intentional.


Just because someone has been staring for many years at the very complex ecology of lower boles and fallen dead wood with the former almost always having a long temporal accumulation of foraging events, doesn't mean their conclusions on what is or isn't IB sign is right to any useful end in itself. On multiple pieces of fallen dead wood they turned out to be mistaken and that was a much, much simpler sample with only one species involved (squirrel).

The accumulation of biotic events over years by scores of potential taxa, each damaging the prior foraging marks, on a low bole which has varying degrees of decay and a confusing heterogeneous pattern of senescence does not lend itself to great precision in IDing what exact species foraged and when.

And unfortunately the observers are biased by hope. They realize that the cameras lose their effectiveness with distance; if IBs are not using the lower bole at least to some minor frequency they have little chance at getting a decent picture(s) and then there has been parts of this effort that were seriously flawed. Surprisingly out of the tens and tens of thousands of cam-pictures they have the only 2 or 3 pictures they say might be IBs ( I agree on one) are from much higher in a tree than 5 feet. They seem to be inexplicably dismissing their own findings after years of work.

Their conclusions that this or that scaling/mark/pit on the lower bole IS IB sign could be supported/strengthened if there was some basic scientific quantifying of the bark's actual adherence in the immediate acres of scaling, the relative amount of scaled bark per acre compared to controls, a detailed description of the habitat, and extensive details of the bole. I believe an experienced observer can eliminate the need to rely primarily on often subjective bole "opinions" if they are experienced enough to accurately gather the basic data sets mentioned in the prior sentence.

They may be documenting some of the occasions when IBs are foraging very low but rudimentary/preliminary data sets and information is missing. They are, as we see, dismissive of strong ecological drivers that shape over millennium most species foraging behavior. Kuhn might agree; he likely rarely or never called out IB presence based on low bole, IB-like foraging but used quantitative larger scale observations, hearing them and seeing them to come to that conclusion.

IB researcher
I think I liked it better when you took your sand pail and stormed away.

I said "a single species was involved (squirrel)" You said: "Nice try. In eight years, I have HUNDREDS of game cam photos of other woodpecker species...When we placed the camera on the tree that was being heavily scaled, ... there was very little, if any, sign of insect infestation on the exposed sapwood on the bole".

Nice try back at you. This double talk isn't all that comforting for the readers who want to hear about solid IB survey methods. It was inferred many times it could be IB by your study. I initially pointed out the chiseling on low deadwood involved only squirrels. Now you howl at me for stating only one species was involved but then you confirm only one species was involved (no insect sign, no insects in the wood and no doubt more clues that an IB was not involved). You had 100+ data points with low birds you should have correlated that with the actual scaling in your hand. You should be an expert on these things if you believe its such a powerful tool.....and such a common mammal as the confusing species.

The readers and Thrush aren't the ones that posted multiple excited, long posts about the potential of upcoming pictures from LA. You shouldn't blame us if we have valid questions or ignore our suggestions and points which you did at least graciously ask about.

Recently fallen wood is relatively easier to interpret than boles.; like you said you were learning. I am bringing up the incident not to rub it in but just to point out how the lower bole which IS a much more complex problem is a poor survey tool in many situations. Lower boles can be several years old and have dozens of putative taxa working there. However I do think the lower bole is used under certain conditions; because of camera issues I guess we must accept that there is little chance of filming the canopy birds well. So you are forced to place cameras. I think above 5 feet is possible if you are forced low.

That's the reality if you insist wrongly there is no way to get a bird in hand. Condors with much greater implications and controversy were completely trapped out of the wild. Its turned out OK despite thousands of doubters.

You whine at me that you have hundreds of peckers on low wood there on film and nothing else. You haven't read the prior comments; before you gave your low bole data it was mentioned repeatedly that almost all the other Picidae species likely visit the lower bole more than an IB per capita. And that's what your data shows (every woodpecker but IB) as was predicted. Your data also supports multiple peoples' assertions that IB visit the lower bole much less per capita. Ignoring hundreds of papers and basic ecological principles on Picidae foraging preferences and predation is not strategic. Oddly you also ignore your own data with all your potential IB picks (one or two, very poor quality) coming from high in a tree. It matters not that you were aiming at roosts; you filmed the upper trunk and canopy and got a possible hit....but negative results low .

Denial and entrenchment will crop into field work but an endless picture chase will and does survive these types of mistakes. There are hundreds of bad pictures already (each frame in the various videos is a picture); its didn't help the IB much.

Unequivocally finding sign of a rare bird in a lower bole is difficult and can in itself only be suggestive of IB presence unless it's carefully determined to be an extension of the usual vertical decay strip stretching from much higher on the tree down. Entire trees and study plots should be examined and empiricalized if you are going to eventually assert the scientific veracity of range wide models.

Tree decay proceeds much more rapidly down from the canopy than up. Trees react to retard decay but do it most efficiently in the side walls of the compartments allowing rot to mostly move down the conductive channels. I see no trip report text that there is any consideration for the spatial and temporal patterns that can indicate the age of bark death and its future movement in situ. The latter is important to camera placement. You have to carefully plan placement and age of bark if you are going to claim IB scaling. Punky bark and large pieces of bark which obviously were not tightly adhered can fall down from gravity let alone biotic input. IBs could be doing it but its not adherent bark and its not convincing as stand alone data.

Mocking others for having data sheets and not knowing their exact work in the best forests in the US is telling. Written data is important for researchers who are serious; this is less important if only "the picture" is the real goal.

You have greatly exaggerated the statistically significant potential for this range-wide bark model abstract while underestimating or ignoring the problems. It is also a minor data set when compared to other types of sets repeatedly presented by scientists and citizen scientists to nominally and efficiently support a claim of Presence. Any bark data set will have many hypotheticals to address along with overly complex nuances; their will be strong doubters. Your bark study is only one scale and its entirely too small.

A competing and neater data set or simple way to report bark data sets has historical examples (see previous posts- for area of bark scaled, adhesion etc.) - Modern ecology is moving towards its string theory where one examines the abstract concurrently on different scales. So how can anyone feel comfortable with your range wide hypothetical survey tool for IBs when your scale is so small and includes only pieces of bark? The scale at the very least needs to include whole trunks and better of course is the whole tree, acre or optimally the forest/landscape as a scale.

--------- Many "researchers" would have, upon discovery of this, chosen to just let the matter drop. We instead opted to make the finding public, so that anyone else could learn from our experience. So much for being "biased by hope"... Shall we say interested in learning?----

A. T. Wayne saw many many more Ivory-bills than anyone else-----hands down (200+). He personally added many species to the SC list, wrote many articles and one of his books, Birds Of South Carolina is a classic. He had rules governing his ornithology and life ---never lie, be meticulous in the field, never brag, never exaggerate, never say or report things that aren't proven. cont
You have been in the field for forty five years. Squirrels are diurnal, its well known they strip and chisel bark especially in drought years. You can't go to any substantial SE swamp or forest and not notice stripping of cypress and small vines and sometimes hickories.

You say----- You are correct that lower boles have a very "complex ecology"... but you ignore the fact that when considered in terms of biomass per unit volume the lower boles are a much richer place, in terms of available protein than the "high branches"------

This has been addressed by me in detail; you have chosen not to advance your side. Vague platitudes and obfuscation do not amount to much. Most times the invertebrate biomass is found higher up. I have presented a good set of hypotheticals when an IB will venture to a lower bole. But ignoring the phenology of tree senescence, death bole ecology and ignoring hundreds of years of anthropogenic take, much of it likely lower on trees, dismissing the fact that even very slight predator pressure can and does influence behavior of birds, etc. all likely contributes to the COMPLETE FAILURE as CT has called it.

Quotes all showing that IBWO may rarely be below 5 feet and prefers the canopy in swamp forests

The ivorybills are, therefore, apparently somewhat adaptable in their food and feeding habits, but forests of mature trees with their dying branches seem to give them the best habitat for securing their food. bent allen smithsonian

Audubon states that "it seldom comes near the ground"; but the birds we have watched behave no differently from pileated woodpeckers in this respect, sometimes working high up in the trees but at other times within five or ten feet of the ground. (note--not below 5 feet)

You state that -----Once again, you are conflating what we think that IB work may look like with a stub that, much like Plate 11 in Tanner, has been fed on quite likely for years by any number of species. We have always maintained that there is a point where putative IB sign is obliterated by other "taxa" (cute dollar a swaller word there, Freddie)as over time, the dead bole deteriorates due to rot and feeding by other woodpeckers. Just FYI, after looking at hundreds of thousands of game cam images, the only other "taxa" that I have ever seen on these older boles are other woodpecker species. You seem to be saying that everyone is coming by to have a snack.--------

There is no internal consistency or critical thinking in some of the things you fellas say/claim. There are many species of diurnal Picidae visiting lower boles as I predicted before you chimed in with your good data ---I didn't think I had to remind you that in LA there are 24 hours/day; some mammals are nocturnal (bears, coons, possums, skunks, rodents, coyotes, etc), your cameras are missing IBs and ALL nocturnal taxa. In addition a large percentage of invertebrate biomass in lower boles is ants, termites, fungi, bacteria and impertinent taxa.

If we all know it's a critically rare species, and we all know that boles are complex, that a sizable percent of IB sign is obliterated by other taxa, that you have not looked closely at high scaling, that all the dietary needs can be met in the higher bole and canopy, etc, etc...............then why do you fellas claim you have delivered an important range wide survey method based on scaling sign?


IB researcher

Please quote where we claim to "have delivered an important range wide survey based on scaling sign..." I want a direct quote of that claim from the blog, or every word you have written is non-helpful histrionics, based on some emotional (jealousy?) response, perhaps because you have no useful alternative to suggest.

Please, the readers can detect the odd denial of one of the main themes of your project (scaling sign of IB) . However I understand your need to put distance between yourself and the great importance you put on the subject.

It's been stated by you fellas numerous times that you are obsessed with feeding sign and scaling. You have not been shy about talking to us about scaling for ~ nine years but now that someone is pointing out legitimate concerns you become a terse denier. There is nothing wrong with someone questioning your admitted compulsions especially in light of obvious flaws and inherent problems which you refuse to address.

In 2011 there was a public claim on IB Lives that you had "sign all fussed out". Your group has posted in every available IB media outlet for years and at least 50 times on scaling etc. Your denial is bizarre. I have suggested various ways to examine the hypothesis you have created, not me. The scaling issue has been correctly treated in a matter of minutes in the field by others; your group wants to write the unabridged bible to IB work and then force feed the community with no discussion. The big bad wolf can huff and puff but It isn't going to happen.

From Coyote home page (~50 of text concerns scaling/work and home page links are to more hypothesizing on work) :

Coyote: Based on our field experience over the past six years, extensive research, and study of Pileated Woodpecker feeding sign outside of known Ivory-billed Woodpecker habitat, we have hypothesized that a certain category of feeding sign is beyond the physical capacity of Pileated Woodpeckers and is diagnostic. The bark scaling shown above is an example of this type of work (more about it here), and it bears a striking similarity to known Ivory-billed Woodpecker feeding sign that was photographed in the Singer Tract in the 1930s. This subject is explored in more depth in a number of posts.

One of your first links on your website:

This article was inspired by my longstanding interest in identifying IBWO foraging sign (a problem I believe I’ve solved, at least in part,) lengthy discussions with Frank Wiley and several others, field observations, and most recently a lot of research.

Coyote site, first paragraph of first post:

It reflects my belief that it is possible to distinguish a certain narrow category of feeding sign as being the work of Ivory-billed Woodpeckers. Since that time, I have spent many days in the field in potential IBWO habitat and also examining feeding sign in areas well-outside the historic range. My basic view has not changed.

Coyote site-- titles of first 3 posts:

Bark Scaling
Cavities and Feeding Sign
Extensive Scaling

These posts are succeeded by a long list of Coyote scaling posts and comments for ~ 3 years that end with squirrels being discovered to be doing IBWO-like scaling (according to your in the field and home office interpretations).

By the way it's in the core, staple literature that IBWOs will never or rarely feed on downed wood including slash. This is based on thousands of hours of collective observation on actual IBs. If you had read this the squirrel work and other issues could of been immediately avoided to everyone's benefit .

It's also in the literature that IBs will avoid certain types of low dead wood even when its has plenty of larvae that IBs prefer. So much for your initial opinion that IBs will feed wherever there is food.

tks IB searcher
Post a Comment

Links to this post:

Create a Link

<< Home

This page is powered by Blogger. Isn't yours?

Older Posts ...Home