Since you want to pit those who don’t believe in the pending fisheries collapse, you’ll have to pit the UN …
Governments doubt dire fishing threat
Agençe France-Presse
Monday, 6 November 2006
There will still be fish on the menu, governments say, despite warnings that stocks will be depleted within 50 years
Governments and the UN food agency have cast serious doubts on a major scientific study that predicts all marine fish and seafood species face will collapse by 2048.
The UN Food and Agriculture Organization (FAO) says that the conservation effort must be improved.
But it says that it is “unlikely” there would be no seafood on consumers’ plates by mid-century, calling the report “statistically dangerous”.
“Such a massive collapse … would require reckless behaviour of all industries and governments for four decades, and an incredible level of apathy of all world citizens to let this happen, without mentioning economic forces that would discourage this from happening,” says Serge Michel Garcia, director of the FAO’s fishery resources division.
South Korea’s fisheries ministry labelled the report “too radical”, and says more scientific data is needed before heeding the call of environmentalists like Greenpeace to set aside 40% of oceans as marine reserves.
Haven’t we been over this before? This cite should be good for now: Was an imminent Ice Age predicted in the '70’s? No. If you read the popular press and television shows you can come to a lot of silly conclusions, like believing that sharks, terrorists, and SARS are coming after you as we speak.
Christ, even George W. “Well, the jury is still out on evolution, you know” Bush “believes” in global warming,** (WARNING: PDF)** even if he waffles over if it’s caused by man or not (yet, interestingly, we should decrease our CO2 output…?).
Do you happen to have any cites for any of this? Do you have any significant evidence at all to bolster your claim that the widely-recognized consensus on the existence of anthropogenic global warming is just “politicization”?
We can certainly disagree about how much the effects are going to be and how certain the predictions are. But I’m skeptical about handwaving claims like this one that all the outcome is unknown. We don’t know for sure, true, but we know enough to make some quite confident guesses.
And when the stakes are as high as they are concerning the consequences of severe climate change, I think it’s only reasonable to respond in accordance with our best guesses, rather than stubbornly waiting out the whole issue until our predictions become 100% certain. If I have pretty good reason to think that I’m driving my car toward the edge of a cliff, I don’t want to wait till I’ve actually driven over the edge before I think about changing direction. Or as a Sanskrit proverb has it, “Don’t wait until the house is on fire before starting to dig the well”.
Had you read the link, you would have seen that the Longjaw Cisco was considered a population of Coregonus zenithicus in 1980, but was later considered a separate species by Smith in 1985 and Scott & Crossman in 1998. It seems that more modern scientists consider it a separate species, the reverse of what you claim in your post. Of course, this is not unanimous: the site also cites Page and Burr in 1991 as considering it a population of another species.
But, if you’ll pardon the pun, this entire arguement you’ve brought up is a red herring. Species are collections of populations. If we can drive populations to extinction, there is no reason we cannot drive a species to extinction. I’ve got to give you high marks for applying nuance to your discussion here, but you’re amoungst those of us who can see through this spin.
Close, but not quite entirely true. The number one cause of extinction around the planet is habitat destruction. Habitat destruction can include, but is not limited to, the introduction of predatory species. This has been known for long enough to make it into the textbooks.
Cite:
From: Pages 68-69 in Primack, R. B. 1995. A Primer of Conservation Biology, Sinauer Assoc.
Just as it is an oversimplification in the situation of the Longjaw Cisco to claim it’s just due to the predation by introduced species without acknowledging that people harvest these fish?
I respect that you have some knowledge of the situation of fisheries, but reading your posts gives me the idea that you don’t respect anyone else’s knowledge of the situation, and that you present a very one-sided perspective on the problem. I’m hoping that you will soon prove me wrong.
Actually, of course, I did read the link, along with a number of others regarding the Longjaw Cisco. The most recent work examines mitochondrial DNA, and comes to the conclusion that they are not different species.
Since populations can be comprised of a very small number of individuals, it is much, much easier to extirpate a population than an entire species. Just like it’s easier to extirpate a population in a lake or on an island. Not spin, a simple fact. Want further verification? Care to guess how many oceanic fishes are listed on the “Red List” as being extinct?
None.
Say what? That citation says nothing about extinctions, only about extinction threats. It also says nothing about habitat destruction including introduced species. According to the Red List, they are separate causes, listed and accounted for separately. The only exception is for introduced species that do not affect the species directly, but do affect the habitat. In other words, introduced species are often a cause for habitat destruction … big news. Introduced species are still listed as a separate cause by the Red List.
But habitat destruction is vastly over-rated as a cause for extinction. Please cite for me, oh, say, three species that have gone extinct due to habitat reduction alone … for each species you cite, I’ll give you three species that went extinct due to introduced species. I’m not talking about theoretical threats, I’m talking about what cause species to go extinct. Number one reason? Introduced species. Look it up.
It has become common, as you say, to claim that habitat reduction drives species extinct. But that’s politically correct science, based on the claims by Wilson that 27,000 species per year were going extinct because of the cutting down of the tropical forest. Despite the prediction, since the '80s when Wilson made his prediction, we haven’t seen one single extinction from his claimed cause.
Virtually every animal habitat is currently reduced from historical areas. Does this mean that if an animal goes extinct, that habitat reduction is a factor? If so, we’d have to say that each and every extinction was caused by habitat reduction, which is nonsense. Most species around the world are in reduced habitats … and most of them have not gone extinct.
People always overestimate the rates of extinction. Let’s consider continental birds and mammals (those living on the continents, as opposed to islands and Australia, where introduced species have wreaked havoc). Care to guess how many continental birds and mammals have gone extinct in the last 500 years?
Read what I wrote. I did acknowledge that humans harvesting the fish had an impact on the extinction. I never said “it’s just due to the predation by introduced species”. It is worth noting that commercial production peaked in the 1930s, about the time that the sea lampreys were introduced. This was followed by a population crash, which of course killed the fishery. Longjaw Ciscos were still around, though, and were seen until 1967 despite the lack of a commercial fishery. Pollution and the sea lamprey killed the longjaw cisco, aided by the human impact.
I respect everyone’s knowledge. However, I don’t agree with everyone. You seem to think I’m just a commercial fisherman. I’m not. You call it “one-sided” … I call it “balanced”. I recommend caution … I recommend better fisheries management … how is that “one-sided”?
I find this a bizarre and intellectually irresponsible demand. What you are demanding that the two of us (random posters on an internet message board in a thread unlikely to last longer than a week) do is replicate the work of hundreds if not thousands of scientists over the course of the last thirty to fourty years. Work that has already been openly published! Why would we want attempt to duplicate that when we can just refer to it? I can see three possibilities for this:
You have an extraordinarily high estimation of both my and your intellectual capabilities and available spare time. If this is true, thank you for your confidence. However, it is sadly misplaced.
You do not know how difficult it will be for us to duplicate here the work of all the conservation scientists who have gone before. I sincerely doubt this: your posts are too articulate.
You know that we cannot duplicate here the work of hundreds to thousands of scientists over thirty to fourty years. This would be a dishonest debating tactic - invite an opponent to do the impossible and snicker when s/he fails.
I do not like any of the above possibilities. I’m hoping that you can elucidate a fourth possibility that I did not consider.
I did. I cited my source above. I try to make my posts informative and cite the source for my reasoning. I also try to cite readily available sources that anyone might obtain and read, and not overwhelm other posters with more than 2-3 sources per post, since it’s unfair for me to try to bury anyone with citations. By contrast, you have chosen to keep your sources secret. I don’t know why you do this.
You have not done so yet. Please see the above. You might still do so in the future.
As I mentioned in my last post, it’s difficult for us to have a discussion when you keep your sources secret, so I had to do the searching for this myself.
I’m assuming you’re talking about this paper: Reticulate evolution and phenotypic diversity in North American ciscoes,
Coregonus ssp. (Teleostei: Salmonidae): implications for the conservation
of an evolutionary legacy (WARNING: PDF) from Conservation Genetics in 2003. I haven’t read the entire paper, but curious about your claim, I perused the tables and “Methods” section. Looking at these, I notice that the authors do not claim to have tested any DNA samples from the Longjaw Cisco (Coregonus alpenae). They might be correct that it’s a member of the same species as other Coregonus members, but you’ll forgive me if I’m skeptical - it seems like quite an assumption that the genetics of a fish one has not sampled belong where they say it does. You should know that there are often proposals back and forth about whether a species should be merged or split taxonomically, and the authors of this paper are not necessarily the last word. Especially when they haven’t tested the mtDNA of the species in question (which is understandably difficult - the species is extinct - but not necessarily impossible.)
An extinction threat is not a cause of extinction? While I have respect for your intelligence, I’m not sure you have respect for mine. You might want to look at the table directly below the portion I quoted: it is entitled “Factors responsible for some extinctions and threatened extinctions.” If Primack’s book is unavailable where you are, the table is adapted from Reid, WV and KR Miller. 1989. Keeping Options Alive: The Scientific Basis for Conserving Biodiversity.
Note for the reader: portions of different posts have been brought together, separated by ellipses, to identify a train of thought.
I’m having some trouble distinguishing your line of thought from this: Scientists are saying things I don’t like and I don’t trust their numbers. I’m imagining that you have a better reason than that. I get that you don’t like Wilson’s estimates - that’s neither here nor there, because I never brought Wilson up. There’s more than just Wilson out there - whose estimates do you like, or is it a general mistrust of biodiversity calculations?
I agree with caution and better fisheries management. What I disagree with is the notion that we can’t drive species to extinction.
This seems to be the accepted modern view. Why? Likely the DNA evidence. My apologies for not providing the prior reference. It says (bolding mine):
Since Longjaw Cisco is a currently recognized (albeit disputed) taxa, and the dispute has been whether it is a separate species or part of C. artedi, and the reference says that all the Cisco taxa other than the Least, Arctic, and Bering Ciscoes (none of which occur in the Great Lakes) are really C. artedi … that seems to cover it.
I asked you for citations of species that have been driven extinct from habitat destruction alone. You haven’t provided a single one, just reasons why you can’t provide one. That’s the difference between a claimed threat and a cause. Most land creatures around the world currently live in reduced habitats. If habitat reduction is such a threat, why haven’t more of them gone extinct? I discuss this question further below.
Wilson is the father of the “reduced habitat causes extinction” idea. You bring up reduced habitat, you bring up Wilson. His calculations have been the basis for the claim that reduced habitat causes extinctions, which has been picked up and promulaged worldwide. All of the modern work on habitat reduction and extinctions uses numbers based on Wilson’s work.
I thought I had made it clear, but I guess I didn’t. I have no problem with biodiversity calculations. I don’t like Wilson’s estimates because there is no evidence to support them. Where are all of the extinctions that Wilson (and you as well) claim will follow from forest destruction? Care to guess how many continental forest birds and mammals have gone extinct in the last 500 years? You said you are familiar with the Red List, so I thought my questions should be easy for you. I keep asking for examples, you keep ignoring that and making claims that you’d have to reproduce the work of “hundreds if not thousands of scientists over the course of the last thirty to fourty years”. Not true. I assumed that, since you were familiar with the Red List, you’d know that information about all of the different examples I asked for is readily accessible.
But since you seem not to be aware of how to go about it, let me describe the process. Go to the Red List Expert Search page. Select for extinct forest birds in all regions of the world excluding Oceania and the Caribbean. Search. Three Hawaiian birds (Hawaii is listed as part of the US, not as part of Oceania). Search took 5 minutes. Result. NO CONTINENTAL FOREST BIRD HAS EVER BEEN RECORDED AS GOING EXTINCT IN 500 YEARS.
Do the same with mammals. Search. Two fruit bats, one on the island of Mauritius, one on Swan Island. Result. NO CONTINENTAL FOREST MAMMAL HAS EVER BEEN RECORDED AS GOING EXTINCT IN 500 YEARS.
Now, the continental forest habitat around the world has been greatly reduced, estimates place it at some ~50-60% of its historical levels. Given the hypothesis that species loss is correlated with habitat loss, we would expect to see several hundred bird and mammal species driven extinct from that level of forest reduction. We have seen none. That’s why I say that habitat reduction is a “claimed” treat … because there’s no evidence to support the claim.
So. Does habitat reduction put stress on an animal population? Of course. Has it ever caused an animal population to go extinct? I suppose it is a theoretical possiblity, but despite 500 years of recorded extinctions, we have no record of it ever happening. That’s the difference between a claimed threat and a cause. At best, habitat reduction is just a supporting factor, and typically the real cause of the extinction is predation (by humans or other species), pollution, or some combination of the two.
Of course we can drive species to extinction, even on the continents, I never claimed otherwise. The passenger pigeon is a prime example. However, it is much more common for introduced species to drive species to extinction, especially in restricted habitats. The difference is that the brown tree snake and the mongoose spend all day, every day, preying in part on birds of the islands to which they have been introduced. Humans don’t.
Look, wevets, the missing link in all of this is that I’m on your side. I am perhaps the most environmentally aware commercial fisherman I know. I believe that humans need to tread lightly on the planet, that we need to be careful about what we do, how we dispose of our trash, how we handle toxic substances.
But I also am a scientist, and as such I believe that science should be based on facts, not emotional appeals. The idea that cutting down Amazonian forests is exterminating hundreds of thousands of species, while emotionally very powerful, is simply not supported by the evidence. I (and likely you as well) don’t think we should cut the Amazon forest … but bad science is not the basis of my argument.
Source: Primack, RB. 1995. A Primer of Conservation Biology. Sinauer Assoc. Page 68.
One should, however, note that considering only North America, 68% of extinct fishes are driven to extinction by introduced species. It is possible that intention believed the situation in North America reflects that of the entire world. (Source: Paxton, JR & Eschmeyer, WN (eds.). 1998. The Encyclopedia of Fishes, page 53.) Intention, you are obviously intelligent and eloquent, but I’m sure your contribution to the discussion would be better if you would check to make sure your beliefs are accurate before you post them as facts.
Not a forest bird, according to the Red List, which calls it “wide-ranging”. Your own quote shows it bred and lived “in areas near rivers, in cypress swamps” In any case, the main cause of its extinction was human hunting.
The 27,000 extinctions predicted by Wilson are supposed to be due to reduction in forest habitat. My statement regarded forest birds. If they can live in other habitats, as the Carolina Parakeet could, they would not be driven to extinction by forest habitat reduction.
This poor bird, however, had the unfortunate distinction of being the only brightly colored bird of the parrot family native to the US. It was hunted to extinction for its feathers.
As I pointed out before, ascribing extinctions to “habitat reduction” is accepted these days as science. Unfortunately, it has been adopted as a scientific principle without supporting evidence. At this point, we are in a circular argument. Habitat reduction has been accepted without evidence. It is now used to “prove” that it is a real threat by listing it as the cause of a bunch of extinctions. But that is circular, that proves nothing.
A bit of history about extinction and habitat reduction is in order here.
The whole theory is based on the observation that as an area increases, the number of species it contains increases. This is called the “species-area” relationship. We find more species in a state than in a county, for example, and more in a country than in a state. These are related by what is called a “power law”, where the number of species increases as some power (around 0.15 - 0.25) of the increase in the area. This has been extensively verified experimentally.
E. O. Wilson, the noted ant biologist, proposed *without evidence *that this would work in reverse — that if we reduced habitat, species would decrease by going extinct. He said that his calculations showed that 27,000 species per year were going extinct from the cutting down of continental forests.
However, he did not write a scientific paper to advance his theory. He wrote several popular papers that pushed the idea that we are in the midst of a “sixth wave” of extinctions (in addition to the five great extinctions in geological times), with this wave caused by humans. (This, despite the fact that the Red List shows that extinctions peaked around 1900 and have decreased since then.)
This claim was immediately picked up and circulated worldwide, without any investigation of its veracity. It was hailed because it gave a way to mathematically calculate the amount of extinctions from a given reduction in habitat. It was widely used, and heavily advocated, by environmental organizations to lobby against the cutting of the Amazon forests.
But there was no evidence, and no scientific investigation of the claim.
Now, if Wilsons theory were correct, given the amount of continental forest reduction that we’ve seen to date, we should have seen on the order of 23 continental bird and 11 continental mammal extinctions every year from that cause. Just since 1988, when Wilson proposed the thory, we should have seen about 600 continental bird and mammal extinctions from that cause. And since forest habitatat had been shrinking for the last 500 years, we should have seen many more bird and mammal extinctions than that.
In fact, we have seen no forest bird or mammal extinctions. Even if we include the Carolina Parakeet, that gives us one. Where are the other 599 extinctions? We might have missed a few, but not 599 … Wilson’s theory simply doesn’t fit the evidence. Extinctions peaked in 1900, and show no sign of a recent increase.
Why doesn’t Wilson’s proposed inversion of the “species-area” relationship work? Intuitively, it seems like it should work, so why doesn’t it? Possible causes are:
The species-area relationship is based in part on an increasing number of habitats, not just an increasing area. There are more different kinds of habitats in a state than in a county. Wilson’s inversion only involves changes in area, not in number.
Species are incredibly hard to kill. They duck and dodge and change habitats and evolve and eat different food to keep from going extinct. Despite centuries of forest reduction, the forest birds and mammals have not gone extinct, simply lived in a smaller area and changed their habits. I asked before how many continental birds and mammals have gone extinct. The answer is, only nine — three mammals and six birds. Despite centuries of hunting and habitat reduction, only nine. Species are amazingly tenacious.
Now, at the moment, through an accident of history, Wilson’s is accepted by mainstream science … as have many other failed theories in the past, from continental drift to helicobacter pylorii. Me, I don’t believe Wilson’s theory, because the evidence doesn’t support it. Whether you believe evidence or theory is up to you, of course.
Intention, you are obviously intelligent and eloquent, but I’m sure your contribution to the discussion would be better if you would check to make sure your beliefs are accurate before you post them as facts.
[/QUOTE]
Oh, please, let’s avoid personal attacks, I’m on your side. You made an inaccurate claim about whether the Longjaw Cisco was a separate species. I pointed out that DNA analysis said it wasn’t a separate species. You read the paper, and still claimed it was. I pointed out where in the paper it clearly said it was a separate species … and now it doesn’t merit a comment?
I’m not claiming it was just your “belief” that Longjaw Ciscos were a separate species, that would an insult to your obvious intelligence. You found facts that pointed one direction, I found more recent facts that point another direction. That’s how science advances, and how our own understanding improves.
I took the facts I used from the Red List, which does not list the Carolina Parakeet as a forest bird. Maybe that’s a fact, maybe not … but it’s not just my “belief”. In any case, let’s say it is a forest bird, one that was hunted to extinction. This does not make any difference to the falsity of Wilson’s theory … we need to have had hundreds of bird and mammal extinctions in the record to verify Wilson’s theory, and we haven’t seen them.
Finally, I’d like to thank you for your participation in this discussion. Disagreement is how science advances.
Which is nice and all, but irrelevant (I won’t even get into the absurdity of claiming that a bird which lives in forests is not a forest bird.) The only reason we’re talking about the Carolina parakeet is your statement that no continental forest bird has gone extinct in 500 years.
For some reason you must have glossed over, not read, or ignored the comment I made above in post #87 of this very thread. Let’s see what exactly I said there:
Your quote from the same source comes from the “Introduction” section of the paper. Did you read this portion:
From page 68 in the “Methods” section, bolding mine.
Can you tell me where the authors demonstrate that they have DNA or attempted to get DNA from a non-extant fish? Seems a little suspect that they can test species A, B, and C, and yet still make taxonomic claims about species D. It’s circular reasoning to suppose that if species D was a member of species C, they’ve effectively tested it.
Your disagreements with continental drift and Marshall & Warren’s discovery of the link between ulcers and Heliobacter pylori have very little to do with this thread. Wilson is at least tangentially relevant.
What the paper said was that there are only four species of Ciscos. The dispute was always whether the Longjaw Cisco was or was not a sub-species of one of the extant Great Lakes Ciscos, or not. All, each and every one, of the several Cisco “species” in the Great Lakes is now recognized as a single species.
Now, we can agree or disagree on what this all means. However, I would not insult you by saying that your view on it is a “belief”. You interpret the facts in a different way than I do. I say the odds of the Longjaw being a totally different species are vanishingly small, because it was so similar to the one Great Lakes species currently recognized that even when it was alive there was dispute about whether it was a separate species or part of the one Great Lakes species. The genetic analysis shows that all the Great Lakes Ciscos, even those which were long thought to be separate species, are one species. Not one of the species which the Longjaw Cisco resembled is a separate species, they are all one species.
You seem to be saying that there is still a chance, however miniscule, that it was a separate species. That’s not a problem. What is a problem is that you describe my conclusions as a belief that ignores the facts. It is not a belief, it is the most reasonable interpretation of the facts.
The Red List does not describe the Carolina Parakeet as a forest bird. The Red List is the basis of my statement that no continental forest bird has gone extinct in the last 500 years. If you have a problem with that, please take it up with the Red List folks.
In any case, as I said, even if we allow it, we have one continental forest bird going extinct in 500 years, with the principal cause being overhunting. We are still missing the 600 continental forest bird and mammal extinctions claimed by Wilson.
Only nine continental birds and mammals have gone extinct in 500 years (one being the Carolina Parakeet), despite extensive habitat reduction on all of the continents. The simple fact is that habitat reduction doesn’t cause extinctions, or we would have seen them.
Thus, the “habitat reduction causes extinction” claim is another in the long list of claims that, although they received widespread scientific approval, are not true. You seemed to think that if scientists agreed on something, it must be true, which is why I mentioned Wegener and H. pylorii.
I see that you’re offended by my use of the word belief, but I don’t see how this could be considered an insult. My beliefs are also that - quite clearly beliefs.
You feel that it’s OK to assume that the Longjaw Cisco had genetics identical to the Shortjaw, and I don’t think it’s OK make that assumption.
Didn’t you just say in post [#88
[/quote]
and
I have a choice of believing you on your word, or believing someone like Daniel Simberloff.
wevets, thank you for your post. First, regarding the Longjaw Cisco, consider the following facts:
Historically, many Cisco variants living in the Great Lakes were considered to be separate species.
The Longjaw Cisco’s status was debated, with some saying it was a subspecies of one of the Great Lakes Cisco species, and others saying it was a separate Great Lakes species.
Modern DNA research shows that all extant Great Lakes Ciscos are one species, and that rather than dozens of species, there are actually only four Cisco species world-wide.
No variants of the other three Cisco species live in the Great Lakes.
The extinct Longjaw Cisco was not similar to any of the other three Cisco species, but was so similar to a Great Lakes species that its status was in dispute.
At this point, since the Longjaw is extinct, we have to go by the odds. What are the odds that the Longjaw was actually the fifth Cisco species in the world? Me, I’d say slim to none, but YMMV.
Next, you quote Simberloff as saying:
You then ask:
Regarding the first paragraph, he claims we haven’t seen extinctions because only half of the US forest habitat was destroyed. However, this 50% reduction should have led to a large number of extinctions, about 10% of all the species in the forest. It did not do so. He conveniently ignores this fact.
Regarding the second paragraph, he says we have not seen the habitat reduction extinctions, because they are not “instantaneous”. But the habitat reductions have been going on for hundreds of years without a single extinction due to that cause.
Finally he says that “research in paleobiology, palynology and conservation biology abounds with examples of species doomed to extinction by habitat change but persisting for extended periods before the death of the last individual.”
Since history “abounds” with examples, perhaps you could give me say five or ten of these examples … until then, the following facts are clear.
Humans have decreased the worldwide continental forest habitat by about half over the past 500 years, with no recorded continental bird or mammal extinctions from that reduction.
Humans decreased the US forest habitat by about half over the last 200 years, with no recorded bird or mammal extinctions from that reduction.
wevets, I’m not asking you to believe me over Simberloff. Science is not a question of “who do I believe”, it is a question of facts.
I’m asking you to look at the facts, to use the Red List search function, and to find me some example of the hundreds of extinctions claimed by Wilson and seconded by Simberloff and yourself. Simberloff did not provide a single example. Nor have you. If there’s really hundreds of bird and mammal extinctions out there from habitat reduction, surely you can provide a couple of examples?
I’m not asking you to believe me, quite the opposite … I’m asking you to provide examples, rather than appeals to “authority”, to substantiate your claims.
