The current thread on whether any animal has been purposefully driven extinct and a few past threads on extinct animals (with, in some cases, minority reports on their perhaps-not-extinct status), lead me to wonder what vertebrates are in that nebulous “probably extinct but we’re not sure” category.
The two I know for sure as falling into that category are the Thylacine (Tasmanian wolf/tiger/carnivore-of-your-preference) and the Ivory-billed Woodpecker. Both have been discussed on threads in the recent past (last few months) as “almost certainly extinct but there have been reports that cannot be dismissed out of hand.”
Are there other creatures whose extinction has this level of questionability? What are they and what’s the background story?
There are dozens, if not hundreds. There are many species that have not been seen for decades or even more than a century. Except for the more conspicuous species, that doesn’t mean they are extinct. Some species have been “rediscovered” after many years without a sighting. On the other hand, some species have become extinct quickly, before anyone even realized there was a problem.
Here a list of extinct birds, and here is a list of extinct mammals. (Caveat: I can see quite a few errors on these lists, and it should also be pointed out they list subspecies as well as species. However, at least they give you some idea.)
Of the birds listed, I know at least the Kinglet Calyptura (previously last seen 1960) and the Madagascar Serpent Eagle (last seen 1930) have been “rediscovered” within the last few years.
Some of the species listed are large, conspicuous, and/or occurred in areas that are very well known, and they are unquestionably extinct. However, it can be very difficult to determine if species that are small, secretive, nocturnal, and/or live in deep forest or remote islands or mountains are actually gone.
I have to say that I find it staggering that in this day and age the prime objective of people searching out near-extinct species of plants and animals is very often to collect them (which in most cases euphemistically means ‘kill and preserve’).
I was reading a book about plant hunters and this guy risked life and limb to scour huge areas of habitat in Africa in search of an orchid that was listed as extinct (but of which he had heard recent reports); eventually he found one; ONE SPECIMEN, so he quickly dug it up and prepared it for preservation.
Not really answering the question at the end of your OP but This site: http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/BHAN-53777B?open
Gives a pretty thorough discussion of the intensive searches that have been made for the Thylacine in the last hundred years. I think we can have as much certainty as we can about anything that the Thylacine is gone.
Today this is almost never the case, and I say this as someone who knows many scientists engaged in this endeavor and who is also pretty familiar with the regulations. Virtually any scientist coming across a species he/she knows to be severely threatened will not collect it. Even if they didn’t care about preserving the species, the bad PR wouldn’t be worth it - all your funding would dry up. And if it is on an endangered species list, it would be nearly impossible to get an export permit from the country where you collected it, and an import permit into your home country.
I don’t know the specifics of the orchid collector you mentioned, but if the story is correct it’s highly exceptional.
In the other thread, there’s the story of a scientist who went to an island in (IIRC) Central America to find some near-extinct birds. He found a dozen or so still alive, so he promptly shot them and preserved them :eek:
You may be right Colibri; my impression was formed from (among other things) my reading of the book Plant hunting for Kew (which seems mostly about people collecting preserved specimens for the herbarium, rather than live ones for the botanic garden) - perhaps there’s just a tendency in such publications for botanists to omit the details of their careful studies before they wade in and start hacking up samples.
There’s a fair amount of people (though I doubt many of them are scientists) who believe that the giant prehistoric shark Carcharodon Megalodon is still around. Is there any possible way a beast of this size could still be roaming our oceans without a single confirmed sighting?
We know for a fact that giant squid exist, but there’s never been a confirmed sighting of a living one. There’s some evidence that giant octopuses (octopii?) exist but, again, none have been seen.
This site, which, even in it’s owner’s words, may contain some unsubstantiated and possibly inaccurate information, does provide some kind of overview on theories regarding the existence of Carcharodon Megalodon, and may give the curious a good jumping-off point for future, more specific searches. Said theories range from Megalodon inhabiting deep ocean trenches, the possibility that the modern Great White Shark may be the Megalodon in just smaller form, and my personal favorite, that Megalodon is responsible for the mysterious disappearance of ships in the Bermuda Triangle. The owner of the site seems to think these theories are a bit unsound, on the more romantic, fanciful side of science and cryptozoology.
I remember reading that a few years ago a species of antelope that was thought to have been extinct for thousands or more years was discovered in a remotely forested area of Vietnam. It seems to have been fortunate in picking a habitat that managed to be ignored by all sides during the war.
Yes, that was my post, in fact. The last dozen specimens of the Guadalupe Caracara, a bird of prey, known only from an island off Mexico, were taken by Rollo Beck, a well-known museum collector. However, a few points are in order: (1) This happened in 1901, when such things were more acceptable; (2) Although these were the last ones seen, this does not mean they were the last ones that existed. Beck may have assumed there were still some left; (3) The basic reason the bird was close to extinction in the first place was persecution by sheep herders. Even if Beck hadn’t shot the ones he saw, it is a virtual certainty that they would have been exterminated by the sheep herders within a few years anyway. I am not trying to excuse what Beck did. While reprehensible, however, it is unlikely that his action actually caused the extinction.
Towards the end of the 19th century, many species, especially on islands, were becoming rapidly extinct due to introduced predators, disease, and other effects. At the time there was a certain sentiment among some scientists that since these animals were doomed anyway, and there was no way to stop it, they had an obligation to preserve some in museums before there were none left at all. (And there are quite a few species known only from paintings or written accounts, of which no specimen remains.)
Such collecting probably contributed to the decline of several species, notably the New Zealand Huia. I worked on a endangered New Zealand bird, the Stitchbird, in the early 1980s, and I did some historical research in which I found that the Austrian collector Andreas Reischek took hundreds of specimens the species when he knew it to be already endangered.
These efforts were certainly misguided. However, for all species of which I am aware, the basic causes of extinction were factors like introduced species, habitat change, over-exploitation, etc., not collecting per se.
This attitude has changed pretty much completely today. You will virtually never find a professional museum collector who would take a specimen if he/she thought it would threaten the species’ survival. I am aware of quite a few cases, where rare or unknown species have been captured, then photographed and released unharmed, even though a specimen would have been of great scientific value.
Botanists have it a bit easier. They can generally collect specimens (leaves, twigs, flowers, etc.) without killing the plant. Some herbs, including some orchids, may be an exception.
Colibri’s post reminded me of a program on Audubon that a friend of mine told me about. They showed a picture of two birds that Audubon had killed “because I’d never seen anything like them before” to which the narrator added, “And no one has ever seen them again.” So apparently, he either killed the last two of a species or the first two of a new species.
