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Fishing warning: is that true?

  1. Dec 20, 2004 #1

    Clausius2

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    Yesterday night I saw a TVdocumental about the nowadays state of fishing industry and oceans. The report forewarned about usual species we eat are in extinction process, and all edible fishes are much less than they were some time ago when global fishing (with large nets) was not practised. So that, they warned about the dangerous situation we are heading to.

    Is it true, or the report was exagerating?.
     
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  3. Dec 20, 2004 #2

    Gokul43201

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    I think only trout are really endangered...and the beluga sturgeon. Most other endangered fish are not common seafood (catfish, loaches, minnows).

    Among the saltwater species, the Atlantic Salmon is endangered too, I believe.
     
    Last edited: Dec 20, 2004
  4. Dec 20, 2004 #3
    It's interesting watching the fishing industry in the Aleutians. You can travel there and find ghost towns that were thriving a decade or two ago, where all residents have moved.

    This is because vast areas that once produce huge amounts of fish have run dry.

    I doubt most of those fish they catch are headed towards extenction now, but it is certainly safe to say that current wild fisheries cannot be continually fished as they are now.
     
  5. Dec 20, 2004 #4
    by by fish

    yes over fishing is a big problem
    they allmost wiped out the cod once thought unlimited in numbers
    many kinds of fish are in danger not just a few
    big asian factory ships are striping the oceans
    even sharks numbers are down by 90% over the last 20 years
     
  6. Dec 20, 2004 #5
    About 100 years ago a 6 ton object washed up on the shores of a beach. It was thought to be a giant squid. In 1970's they did a DNA test on the sample and found it to be indeed the dead body of a giant squid. Today they a make a big deal of a 300+ pound giant squid which was witnessed or caught about a year or so ago. The oceans are being depleted at an astronomical rate. The oceans are being posioned also daily with millions of tons of chemical pouring from the mouths of rivers. The plankton and the reefs are being destroyed. It is just a matter of time.

    Note: The day we go completely to fish farms they will say we do we need all these regulations for dumping in the sea. The sea is a big place right. Lets dump it in the deep sea trench. The oceans will become sludge, never underestimate the greed and lack of responsibility of the human race.
     
  7. Dec 21, 2004 #6
    Thanks Tenyears. You took a perfectly reasonable position on the issue and made it sound rediculous by linking unrelated issues, making wild claims that you could never substantiate and by pointing fingers at no one at all. If you could kindly move to the other side of this issue it would be that much easier to make an argument for conservation.
     
  8. Dec 21, 2004 #7
    Tuna and codfish among others are going down in numbers very fast as well.
    Less and less fish reach the age to reproduce, they are beeing caught before.
     
  9. Dec 21, 2004 #8

    Phobos

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    There are about 120 fish species that are listed under the federal Endangered Species Act. There may be others on state lists.

    And that's just what's known in the U.S. alone.
     
  10. Dec 21, 2004 #9
    The point was less than one hundered years ago there were monsterous fish in the ocean. In 50 years we have wiped them out. I anger to the media because they sensationalize a 300 pound giant squid when in reality they are being starved and can no longer support the tremendous sizes that they were not so long ago. The media which is being used likes to blind us to the reality by making something small seem like such a wonderful or amazing thing.

    The oceans are being polluted daily in an ever flowing stream. These pollutants will slowly kill the micro oraganisms and from there begin to starve aspects of the food chain. Slowing up on the fishing will only bring them back somewhat because the great affect is not only the fishing but the slow and inevitable destruction of the habbitat.

    The wild claim was in the 1979 guniess book of records usually a reputable source. There are two types of people in this life those who agree with me now and those who agree with me later with their mouths quite open.
     
  11. Dec 22, 2004 #10

    iansmith

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    Most of the polluant do not kill the microorganism. In fact, some polluant help some microorganism to grow to very large population and sometimes the pollution is the microorganisms. These microorganism population then to be toxic in large numbers and in part kills some of the macrofauna. Polluant also directly kills the

    We also known very little about the giant squid and make the statement is quite bold. How do we know the squid are starving?

    The other problem with estimating the population of fishes is that the surveys have flaws. The most commercial fish population are very low; however, population of some of non-commercial fish population are doing quite well.

    I think the best picture for he effect of more efficient fishing technic that lead to overfishing is a postal card I have seen on the east coast of canada. The post card has a sentenre written in black: "In cod, we trust" but "ed" is added in red after trust.
     
  12. Dec 22, 2004 #11

    matthyaouw

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  13. Dec 22, 2004 #12
    You are incorrect about the size of the largest found giant squid; Guiness is not an acceptable source of scientific information. There are almost certainly large squid out there, but there is no evidence there are fewer large squid than one hundred years ago.

    On the contrary, you are incorrect about wiping out the squid population. All evidence seems to point to a growing giant squid population, due to overfishing of competing sealife. The entire basis of your argument is completely without merit.

    And a third type of person who finds unbacked claims of rediculous proportions to be unacceptable. Provide better data. You are hurting the argument for conservation by relying on poor induction and mediocre fact sources.
     
  14. Dec 23, 2004 #13
    Locrian, the squid which have existed to that size are disappearing for they cannot sustain themselves at such size with the dimminishing food sources. I did not say that there were no squid only that the squid of that size. The largest of the chain are affect first?? Read it for youself for the place that did the DNA test was a credible source. There were also eye witness reports which was on I think of the discovery channel for WWII vets and soldiers. Their ships where sank the aircraft went down and they were all floating in the water. They were picked off one by one until there where only a couple left. The man said he waited for his turn as the large arms would pull the men under screaming. For him they never came. There was another soldier who was repsonsible for the radar on their destroyer. As he was viewing the readout it went blank. After a while the radar came back on. When they reached port he reviewed the front end of the ship where the radar bra was. He found what looked to be a large piece of tooth embeded in the material. He had it analyzed and found that it was part of the beak of a giant squid. It was estimated the squid would have to be over 200 feet long for a piece of that size.

    The media and the world want to keep you asleep to simple facts and you want to keep yourself asleep to yourself. LoL


    As for the the pollutants my words stand no matter what you believe or think. I have seen the day when large portions of ocean were covered in muck. Never underestimate the stupidity of humanity. Arrogance and greed are our tools.
     
    Last edited: Dec 23, 2004
  15. Dec 23, 2004 #14
    This is clearly untrue. I've provided evidence for this. You have provided no evidence for your statement. Your inability to create a logical argument isn't acceptable.

    Your arguments are bad for conservationism.
     
  16. Dec 23, 2004 #15

    Astronuc

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    Try these sites for some background.

    http://collections.ic.gc.ca/cod/contents.htm

    http://geogate.geographie.uni-marburg.de/vgt/english/canada/module/m2/u3.htm


    The populations of food fishes, like cod, are decreasing, and some species may actually be disappearing. This is a combination of mortality (which increases with pollution) and overfishing. The problem is simply that more fish die or are harvested than reproduce (and this could be modeled by a simple first order differential equation):

    dN(t)/dt = - Rate of depletion (mortality rate, harvesting rate) + Rate of reproduction.

    BTW - the EU backed away from an outright suspension of fishing and accepted some limited fishing. The fishermen and fishing industry feel this is still too much, but many environmentalists feel that this is not enough.

    Any commercial fisherman can tell you that they have to go farther to find an adequate catch, but still find less fish than 10 or 20 years ago, and the fish generally tend to be smaller. Ocean fishing is a problem - many fishing fleets are going very far from their country of origin to catch fish - because they have overfished in their own backyard.

    It is a bit like the situation if the lumber industry were cutting trees but not replanting them. It would take little time for the forests to be depleted (depending of the rate of harvesting).

    Perhaps, the problem is that many, if not all, who harvest the fish from the ocean do not expend any effort to restock the seas. There are examples of aquaculture (specifically fish farming), e.g. salmon farms, but raising fish in close proximity leads to problems with disease and contamination. Clearly there is a need for improved methods in fish farming/aquaculture, as well as a comprehensive plan for replenishing the oceans.
     
  17. Dec 23, 2004 #16

    matthyaouw

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    What exactly do you mean by this?
     
  18. Dec 23, 2004 #17
    Astronuc, very nice post, but don't let idealism of man or science every make you think that the common or uncommon scientist is qualified to understand the balance of nature in it's entirety for they cannot. It is one planet one system working in unisone with over a billion years of development. Only the arrogance of humanity could believe that it could understand that balance. It is so interwoven so complex that one can only be in awe more that one could admit with any certainty that one could create a balance for the imbalance we have caused. Restocking the oceans would with choice fish would only end in disaster, disease and possiblly the elimination of large species of other fish which create a worse imbalance unseen. The recoil would not be noticed at once but then it would happen and bang it would be over. The words we did that would resound over and over and over.

    You are more than on the right track but pollution must be handled. They think it will only kill the oceans. LoL It will do far more than that...
     
  19. Dec 23, 2004 #18

    I see things and they happen what do you think that means? Maybe nothing, maybe everything, but in the end it still means nothing.
     
  20. Dec 23, 2004 #19

    Astronuc

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    I would not suggest this, nor did I. Certainly use of limited species (e.g. monoculture) would be disastrous. A single disease could wipe out the entire stock.

    The fishing industry must be made to limit the harvesting to assure recovering of the endangered species, or the fishermen will soon find out that there are many more fishermen than there are fish, or there are no fish at all.

    The other solution is reduction of pollution. Improved water treatment facilities, reduction of industrial effluents, reduction of agricultural waste are necessary to ensure viable fish populations.

    Certainly it is easier said than done.
     
  21. Dec 23, 2004 #20
    The only thing similar to this that I've heard of is that lakes and rivers can have high mercury counts in them and the fish somehow absorb it into their bodies. I don't know about everywhere else but it's not uncommon to see a sign in South Carolina that warns about eating more than one fish a day or even not eating any fish from the water source.
     
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