Do you believe there is intelligent life anywhere else in the Universe? I suspect most scientists think there is, not because there is any hard evidence for such a belief; there is NONE (no documented crashed saucers with little green men, no radio signals received despite decades of scanning for such, no messages in cosmological bottles saying 'Hi ya Earthlings!'). Yet most scientists likely believe such because of the probabilities involved --- given BILLIONS of stars with potentially BILLIONS of planets, the likelihood that we reside on the absolute only one to harbor advanced lifeforms (....and yes, I'm assuming there IS intelligent life on Earth ; - ) is so miniscule as to be beyond debate.
I mention all this because the Ivory-bill debate is of a similar form. The scientific evidence supporting Ivory-bill existence is weak... but it is head-and-shoulders above the huge absence of evidence for Ivory-bill extinction. For the umpteenth time --- NO solid scientific evidence has yet been presented for the extinction of this species; NONE, EVER, NADA, ZERO ACTUAL EVIDENCE, just speculation and conjecture. And when I ask people for evidence, all I get is a recitation that persons A, B, and C, went looking for IBWOs in places X, Y, and Z, and couldn't find any. Well, DUUUUUHHHHHHHH!! Meanwhile persons D, E, and F claim they HAVE seen them and places T, U, and W haven't even been adequately searched... EVER. As long as skeptics start with an unproven and biasing assumption ('Ivory-bills are extinct') they will lack the objectivity and open-mindedness required in a scientific review of evidence. You can't declare things extinct that are being repeatedly reported, without thorough searches. Some want to believe that a lone grad student (a grad student mind you!) did such an infallible study with flawless conclusions, that no IBWOs could have persisted through the 1940's. I'll remind folks yet again of the MOST important passage in James Tanner's entire monograph (from his "Introduction"):
"The chief difficulty of the study has been that of drawing conclusions from relatively few observations, necessary because of the extreme scarcity of the bird. My own observations of the birds have been entirely confined to a few individuals in one part of Louisiana... the conclusions drawn from them will not necessarily apply to the species as it once was nor to individuals living in other areas. The difficulty of finding the birds, even when their whereabouts was known, also limited the number of observations. Especially was this true in the non-breeding season. With these considerations in mind, one must draw conclusions carefully and with reservations." [all italics added]"Draw conclusions carefully and with reservations" --- hmmm... what a novel idea!!!
...And the skeptics' current mantra that anything which hasn't been photographed by humans doesn't exist should be of interest to physicists who tell us that over 90% of the universe is made up of "dark matter" never seen (let alone photographed) by human eyes.
But seriously... the arrogance and ego-centrism underlying certain skeptics in their persistent judgment that ALL sighters (every one of them over 5 decades) must be wrong, mistaken, foolish, incompetent, dishonest, fanciful, delusional, crazy, or worse, while they, as armchair skeptics often far from the scene, of course know better, is also NOT a part of good science. I need only believe one claim in the last several years; skeptics must disbelieve thousands of claims (and yet those same skeptics will readily accept and turn in brief and undocumented sightings for bird counts all the time, with no verification whatsoever that the spotters even left their living room, let alone saw the species being recorded).
Most English words are vague and ambiguous --- "extinct" is NOT!! It doesn't mean there are less than 30 left, or only 5, or maybe only 1; it means there are ZERO left, zero anywhere. It is a word to use with utmost care, given the difficulty of 'proof.' Obviously, the documentation of a single Ivory-billed Woodpecker will mean the species isn't extinct and NEVER has been. All of us in the birding community should have a vested interest in this species being found and protected (even though it will likely be too little too late); too many on the skeptical side have so painted themselves into corners by now that they have a vested interest in the species never being documented. Pity. (...or so it seems to me).
And just to play catch-up on a few things:
1) as far as Rich Guthrie's claim, I find it credible, but still don't have enough details to be fully convinced --- and it is really somewhat inconsequential since photographic documentation is now required; ALL sightings are immediately considered suspect in too many quarters.
2) An Oxford University Press interview here with Auburn's Dr. Hill: http://blog.oup.com/2007/05/birds/
3) And with summer approaching, if you like trashy pulp fiction you may wish to read this science-fiction offering:
http://www.worldtwitch.com/ivorybill.htm
ooops, gotta go now, there are some little green men knocking on my window....
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14 comments:
Just so I understand your standards of evidence, could you name some species you think have gone extinct in the last 100 years and state why you think they are extinct? Thanks.
First, it's always a matter for me of probabilities, NOT certainty, and the key is whether the probability of existence appears to be well under 50% or well over 50%. I could only discuss the likelihood of extinction of other N. American birds based on the very limited study I've done of them, so rather than give an 'off the cuff' list of birds I think are likely extinct (70%+ probability) I'll just mention the two most classic cases.
Based on a number of factors, I think Carolina Parakeets are likely extinct (a view I could change in a heartbeat BTW if someone demonstrated to me that there have been sighting claims for the bird every single decade in suitable habitat, at least some of which are from credible observers). Similarly, I take it as well-over 50% likelihood that Passenger Pigeons are extinct, BUUUUT... if a competent biologist straggled out of some unexplored Mexican mountain valley tomorrow and said he'd seen Passenger Pigeons I would want the report FULLY followed up (not just blown away like so many IBWO reports). And to push the example farther, suppose that biologist had definitive video of the birds... while the rest of the world went gaa-gaa over the film, I would shrug my shoulders and say, ' what's the big deal; you go to a place humans haven't much explored and you find a bird humans haven't seen for 100 years; SO WHAT!!' It should NOT be a surprise that human knowledge and understanding of the natural world is less than perfect and complete... yet many prefer to act as if it is (what we don't know about the world around us dwarfs what we think we do know). And BTW, 100 yrs. isn't all that long of time.
Again, I feel many of the numerous sightings of IBWO over the decades (and not of Carolina Parakeet, Great Auk, Passenger Pigeon) are because the IBWO is shown in recent field guides (Robbins, Golden Guide from the 1960's onward, Peterson's 4th edition, etc.) and the other extinct (or possibly extinct--since we can never know for sure) species are not.
Could this account for all reports? Who knows? As you have stated previously, there has been a failure to find a breeding population of IBWO all these decades. IBWO were known to be fairly easy to find when at the nest. (And this has not been found subsequent to the recent claims in Florida and Arkanasas.) To me the failure to find a breeding population in the vicinity of the recent claimed sight records is damning.
Again, why does all this matter? Because the USFWS is spending considerable quantities of scarce conservation dollars on fruitless (after 3 years) IBWO-chases. Do we want to look back in 30 years and say, "gosh, too bad the Red-cockaded Woodpecker did not get that $10 million instead of the IBWO in 2007--now they are both extinct!"
Thanks for the explanation of your criteria for accepting or rejecting the claims of "extinction".
So since after a century of no sightings of Carolina Parakeet you feel you can say they are "likely extinct", would it be reasonable to assume that sometime in in the middle of 21st century you would agree that people could consider the IBWO "likely extinct" - assuming that any evidence gathered in the next five decades is of similar quality to what has been obtained in the last five?
yes, I'd expect long before the middle of the century for this issue to be settled given the amount of currentinterest and searching (but it does depend on the amount and quality of evidence forthcoming).
I believe P. Coin's surmise about field guides might account for many of the 'novice' birder reports of IBWO, but isn't likely behind the claims from other more experienced, credible sighters of the past.
As to "breeding populations" I'm not sure what that means -- does one pair in one 15 sq.mi. area, with another pair in an adjacent 15 sq.mi. area represent a 'breeding population' -- in short there may only be distantly dispersed pairs left representing "populations" within a given state but true 'needles in a haystack' to find.
There will always be money issues, and yes 'charismatic' creatures generally get more than their share of available funds (and much for the IBWO is coming from private sources as well) -- this argument is I think unresolvable, in so much as some would argue NO funds should go to 'endangered species'at all given other pressing issues the money could be used for (starving children, farm subsidies, AIDS prevention, fighting terrorism, or lining the pockets of oil executives and Republicans ;-) In the end, even if the species is documented, I doubt it can be saved, and in that sense the money may be wasted -- but that is the price we now pay for having NOT put forth the time, energy, and effort to locate the birds 30, 40, or 50 yrs. ago.
"...even if the species is documented, I doubt it can be saved..."
If it has survived thus far, why should it fail now, especially considering how little habitat was available decades ago compared to what it has today? Wouldn't you think that the metapopulation has been on an upswing in recent decades? Are you suggesting that southern hardwards are now at their zenith and from here out it's doom and gloom? I'm sorry, but I have to wonder why the ivorybill needs us at all right now, especially if you're correct (as I want to believe) and the bird persists today despite our best effort to eradicate it decades ago.
I hope I'm wrong but I'm VERY pessimistic about the future for all wild creatures (well, vertebrates) on this planet given the path humans remain on. I expect the last 60 yrs. will look like a piece of cake compared to the ecological disasters looming for the next 60 yrs. While we fuss and fume over correcting global warming, many other catastrophes are likely already 'baked' into the system from human actions through the 40s, 50s, and 60s, and just haven't reached their unavoidable fruition yet.
The IBWO can eke out a living for a few more human generations, but realistically longer term, I just don't see it, or the C. Condor, nor 100s of far more common species surviving in the wild in N. America (but, hey, I'm all for trying).
"Do you believe there is intelligent life anywhere else in the Universe?"
No. And after reading IBWO TB blog posts like this one I question the intelligence of life here.
geee, Carl Sagan would be most dismayed that you don't think intelligent life exists elsewhere in the Universe.
But then I suspect you don't believe in evolution either... and, is the Earth spherical or flat????
As to "breeding populations" I'm not sure what that means
By "breeding population", I mean birds that nest and raise young successfully. Any species is going to die out pretty quickly if there is no nesting. That is apparently what happened to the Passenger Pigeon--despite large numbers still present, breeding failed, and the species was almost gone in a decade.
does one pair in one 15 sq.mi. area, with another pair in an adjacent 15 sq.mi. area represent a 'breeding population' -- in short there may only be distantly dispersed pairs left representing "populations" within a given state but true 'needles in a haystack' to find.
Yes, and there's the rub. I doubt that birds scattered so widely would be a viable "breeding population"--how would birds find mates? Such a group of small populations could just not persist for long. Typically, young birds disperse after fledging, or perhaps in subsequent years, and they have to find a mate somewhere. If the population density is too low, young birds will not find mates and raise young. The population will then die out. An entire species can die out this way. Don't you think that is likely what happened with Bachman's Warbler? It has almost happened with the Red-cockaded Woodpecker--many small populations, but widely scattered and birds not likely to find each other. The species is in real trouble.
The idea that IBWO could persist for decades at very low population densities is a "just a hypothesis", as you are so fond of saying for the hypothesis of IBWO extinction.
In addition, the "persist for decades at ultra-low density hypothesis" runs counter to what is known behavior of the IBWO when it was studied--by Tanner and earlier people as well. From Allen and Kellog, Recent Observations of the Ivory-billed Woodpecker, The Auk volume 54: 164-184 (1937), (PDF):
"This [AOU check-list distribution of IBWO] does not give one very important fact in the distribution, namely, that the birds are non-migratory and moreover they are probably sedentary. It is our belief that most individuals spend their entire lives within a few miles of the place where they are hatched and develop little Ivorybill communities. These, when left to themselves, may develop such local abundance as reported by early observers and give a wrong impression of the general status of the species. On the other hand, one not knowing the exact whereabouts of one of these communities might search for days in suitable forest cover within a few miles of the right spot without discovering the birds. The birds which we discovered in Florida were within a mile of the place where a hunter reported having seen three and shot one three years before. The birds discovered in Louisiana in 1935 [Singer Tract] were apparently close to the spot where Beyer (1900) reported collecting seven specimens nearly forty years previously; the place had been known to local residents for fully as long and had been reported by Pearson in 1932."
Though scattered, the populations apparently consisted of groups of birds, not just one pair. Yes, they could be hard to find, but once one found a colony, it could be refound, even years later. That's what I mean by "failure to find a breeding population".
Furthermore, this sounds like the current populations of Red-cockaded Woodpeckers--absent in large areas, but easy to find around their colonies. I wonder if the IBWO is/was a cooperative breeder like the RCW, with young of the year staying around to raise the next year's young. Jackson says that cooperative breeding was not known to occur, but it seems the species was never studied in sufficient detail to know if this was true--banding of individuals, for instance.
There will always be money issues, and yes 'charismatic' creatures generally get more than their share of available funds (and much for the IBWO is coming from private sources as well) -- this argument is I think unresolvable, ...
The fact is, the USFWS, etc., does not have a very large budget for endangered species conservation, and funds need to be allocated based on good science--priorities have to be set, and the IBWO "rediscovery" is distorting priorities for endangered species. The Red-cockaded, etc. can likely still be saved if we spend our public money wisely.
In the end, even if the species is documented, I doubt it can be saved, and in that sense the money may be wasted -- but that is the price we now pay for having NOT put forth the time, energy, and effort to locate the birds 30, 40, or 50 yrs. ago.
Well, if it is really so far gone, then I feel no public money should be spent on it, and funds should be reserved for species that can be saved. This sort of triage happens all the time in public policy. The US Government, conservation community, etc., have all made mistakes in the past--to base current policy on trying to correct uncorrectable mistakes made in the past seems unwise to me. (More should have been done to save the Great Auk, Labrador Duck, Passenger Pigeon and the Carolina Parakeet, but I don't think that means we should spend $10 million each per year searching for them and procuring their habitat in case they might still exist.)
For the record, regarding your comments to an an anonymous poster (not me) above:
-I think it likely intelligent life exists elsewhere in the universe
-I believe in evolution by natural selection, and "know" it to be true based on extensive fossil and other scientific evidence
-I believe the earth is round, in fact I know it to be round from personal observations--having seen ships sail below the horizon, disappearing from the bottom up.
we simply have to agree to disagree on this Patrick: yes, the sparse-populations'-persisting hypothesis is nothing but a hypothesis; the reproduction instinct is powerful, and even land-based creatures have a knack for finding one another over great distances when breeding is desired (sometimes through pheromones, sometimes sound, sometimes probably other mechanisms). I really believe people totally underestimate the huge advantage that the simple act of 'flight' bestows upon birds: flight is a means of quickly evading predators or detection, and of quickly finding new habitat and potentially new mates.
Tanner believed breeding pairs needed a MINIMUM of 6 sq. mi. of territory. IF he was right and that's a MINIMUM it would not be unusual for individual pairs to be separated by 10-15 mi. during the breeding season. That whole 'colony' business I think pertains only to non-breeding season (but feel free to correct me on that). In any event creatures can certainly often alter their behavior as needed by circumstance and population; i.e. they could be sedentary when that served their purposes, and become more nomadic as needed for food/habitat (too often we treat all other creatures as unthinking, unchangeable automatons and only humans as having 'free will' as it were).
Again, I won't argue the financial case with you; I think it's a perfectly valid argument, except that it applies to EVERYthing -- any expense of money you show me, I'll find a 'better' use somewhere those dollars could've gone to. I love our space program, BUUUT, despite NASA's self-serving list of societal gains from sending men to the moon or sending robots to Mars (implication being these advances wouldn't have happened without the space program), I believe the only REEEAL reason for those efforts are the human 'wonder' of it all, and for eventual human colonization of moon/Mars -- in actuality, there are MANY human needs on Earth the money could've better served (but I'm glad it didn't). I would hope your grandchildren have at least a slim chance of seeing an Ivory-bill in their lifetime; I just don't expect you're grandchildrens' grandchildren to have much of a chance (but nor would I expect them to have much chance of seeing any 'endangered species' of today).
Finally, I'll admit that this whole saga for me, is no longer about saving a particular species, it is about the process by which scientific argument and methodology proceeds, and applying that in future instances -- I think there are huge lessons to be learned (and so do skeptics, only a different set of lessons).
I'm going to disagree with your math. If a pair needs six square miles for a territory, that is about 2.4 miles on a side, and that would correspond to a mean separation between nests (if in center of territory) of 2.4 miles, not 10-15 miles. A 10-15 mile separation would correspond to a 100-225 square mile territory.
I don't know about nesting season versus non-nesting season for the "colonies". Allen and Kellog (PDF) note that nests were sometimes found close together:
Ridgway (1898) reported finding two occupied nests in Florida within two hundred yards of each other. We did not discover nests so dose together as this, but three pairs were nesting within a radius of two miles.
Three pairs within a radius of two miles sounds semi-colonial to me. Again, one or two observations, but that is all we are ever likely to have, and that is not based on just "Tanner's birds", but observations going back into the 19th century.
Jackson's BNA account summarizes:
Allen and Kellogg (1937) suggested that the Ivory-billed was characteristically sedentary and might live its entire life in one area, establishing small, local populations isolated from other such populations. Evidence supporting this suggestion includes observations in the Singer Tract of Louisiana (e.g., Allen and Kellogg 1937, Allen 1939, Tanner 1942a) and records of large numbers of specimens collected from various discrete, isolated areas (Jackson in press).
This sounds very suspiciously like the way Red-cockaded Woodpeckers are dispersed in colonies today--a bunch in a few places, and few and far between otherwise. Cooperative breeding? Perhaps not--I don't see any references to it in other Campephilus, doing some quick web searches. It is apparently known in the Great Slaty Woodpcker from SE Asia. (Oh, it's a paper by Martjan Lammertink! I can't read the whole paper--restricted access.)
Finally, I'll admit that this whole saga for me, is no longer about saving a particular species...
Golly gosh, for me it was about the Ivory-bill. Cornell had me convinced the IBWO was not extinct for about 4 months. Then came the Auburn group. Somebody said it was like Lucy pulling the football out from under Charlie Brown--over and over, and he still believes. I've felt like that for every IBWO claim since I was a kid--run, whoosh, KLUNK!
"it is about the process by which scientific argument and methodology proceeds"
Pure speculation by celebrities is evidently your preferred approach.
Patrick is nothing if not persistent and perspicacious :-)... Good point on the math, but even at that bare minimum of a couple mi. apart in dense canopy, cavity-dwelling birds could be exceedingly difficult for humans to locate, let alone photograph. And without the photograph, skeptics are asking ad hoc why are there no sightings -- but it's circular, there no sightings only if you dispute every sighting. For lack of a photograph a lot of credible people are being dragged through the mud (current and past) --- I won't list names but I would need to see solid evidence for the foolishness or pathology of all these folks to conclude that all their claims are to be ignored just because alternative explanations can be concocted.
And we simply disagree on the ability of flying creatures to find one another over large expanses for breeding purposes; or for that matter the ability of birds to locate habitat, food, or anything else required for survival. There are difficulties involved, and that helps explain the decline of the species, but it doesn't necessitate extinction.
And I'm sure every believer out there empathizes with your "run, whoosh, KLUNK!" feeling; I guess just try holding onto your blanket a little tighter for a little longer :-)
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