Posted on 06/29/2005 2:58:30 AM PDT by Einigkeit_Recht_Freiheit
PORTLAND, Maine — The collapse of cod stocks off Nova Scotia changed the marine ecosystem so dramatically that it may be impossible for cod to recover, according to a study by Canadian scientists that could have ramifications for cod stocks at Georges Bank.
Once the top predator, cod is now a bit player in waters off Nova Scotia. Its population on the Scotian Shelf has plunged 96 percent since the 1850s, according to archaeological evidence and old fishing records. In its absence, the entire marine ecosystem has been transformed, said Ken Frank, who co-authored the report published recently in Science magazine.
"It was always thought that the effects of overfishing were reversible," Frank said. "It's pretty shocking when you stop fishing, the fish don't return."
The research of Frank, Brian Petrie, Jae Choi and William Leggett could have ramifications for Georges Bank cod, which also has been decimated by overfishing.
Frank, who works for Canada's Department of Fisheries and Oceans at the Bedford Institute of Oceanography, says the virtual disappearance of cod and other large species such as haddock, flounder and hake led to what scientists call a "cascade effect."
As the population of large predators declined, the fish they prey on -- herring, shrimp, crab and lobster -- have undergone a population explosion. That means cod, which used to sit on the top of the food chain, has now been replaced by smaller fish, Frank says.
Cod's departure is felt at the bottom of the food chain, where zooplankton and algae are now being depleted at a faster rate because more and more fish are feeding on them, he says. Eventually, the lack of food could bring about a crash in the numbers of fish, he says.
Frank says it's unclear whether cod can make a recovery in this new environment.
A big obstacle, he says, is that cod spend the early parts of their lives at the bottom of the food chain. Cod eggs, larvae and juvenile cod are food for other fish. Because there are fewer adult cod, there are now a larger population of fish to eat the young cod.
"The king of the jungle are typically large as adults and are safe," said Robert Steneck, a University of Maine scientist who has studied the cascading effect in the Gulf of Maine. "With overfishing, we are left with babies, and they are not safe."
Because of cod's decline, lobster populations have exploded to record levels, despite increasing fishing pressure, Steneck says. And lobsters today account for more than 70 percent of the total value of Maine's marine resources.
While that may seem like great news, Steneck says, fishing communities have become dangerously dependent on lobsters. "If anything happens to this one species, we have a disaster on our coast," he said.
As we change the percentage of carbon dioxide in our atmosphere we are messing with the whole system and don't know the consequences. Sounds like a big gamble.
Got my flame retardents on for the head-in-the-sand, man-is-too-puny-to-affect-nature crew.
I guess all the fish are being cod.
Oh my cod....say it isn't so. I wonder if it will be so ten years hence.....
Sperm Whales no longer play the area to eliminate the squid which has had a population explosion as they eat the cod unmolested by any predatation.
Oh come on! Does the author really believe that fishermen are so stupid that they could not learn to fish for and profit from what ever species filled in the gap if Lobster numbers declined.
When cod declined fishermen learned to fish for lobster. Does the author really believe that Lobster fishing is the absolute limit of mans ability to adapt?
Seriously though, Why don't they do what they did with Atlantic Salmon on the Penobscot and raise cod in fisheries to be released when they are big enough to compete with the other species?
According to your logic, I guess the people are going to eventually learn to love to eat algae and plankton stew.
No according to my logic nature like man is adaptive, and if lobster declines, another species that eats algae will proliferate.
Empty nets just might be an indicator of fish numbers.
Do you think there are still wild Elk and Buffalo all over the Eastern United States? After all its a big place, you can't see everywhere at once. They might just be hiding, right?
Probably. Sad isn't it?
No, but there seems to be a lot more deer, cows, and people, than there once was.
these are not men, they are Lobstermen!
If you beleive in evolution, then some of those small, algae eating fish will turn carnivore because an ecologial niche is available.
Another factor that is left of of just about every article on fisheries is that for most species the fishing boats set their nets on spawning stocks. It is easier to catch more fish that way. I told them that the Pennsylvania Game Commission had figured out that shooting gravid deer was bad for the deer population ( and for the hunters) about 100 years ago.
Whenever you see a journalist use the word according, the alarms should sound! The quoted is the only "fact" and everything else is opinion. Yet this fact is probably opinion. The writer does nothing to support the "fact" or advance the knowledge of the reader.
Now, who expresses the opinions composing the remainer of the article?:
BIO is a modern oceanographic research facility, established in 1962 by the Federal Government of Canada and is located on the shores of the Bedford Basin in Dartmouth, Nova Scotia.
http://www.bio.gc.ca/info/about-e.html
" So why would a mouthpiece for the Canadian government be whipping up hysteria over cod? How about this:
In its 2003 summary on the provincial economy, the government notes fisheries incomes rose from $170 million in 1991 to $374 million in 1999, the last year tax data were available. The total value of fish landings hit $515 million last year, compared to an average of $260 million during most of the 1990s." http://www.creativeresistance.ca/canada/2003-the-codless-sea-cbc.htm
So do you think these fisheries contributed to the political campaigns of whoever is in government? Hmmm...
And how about this:
The tension has eased somewhat. Now the main complaint from both fisherman and scientists is Ottawa's lack of money for scientific research. Id.
So notwithstanding the lack of funding and study, these three "experts" have it all figured out. Ooookay. This study seems to be, at least in part, a scientists play for funding. Yet the writer does nothing to identify the source of any potential bias for the opinions of the "experts."
I am not denying there has been a change is the population of the waters resulting in frictional unemployment on the land. I just doubt that a government funded study has the answers.
Government funded studies are the answers to those who's rice bowl are government funded studies.
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