Fishing's global footprint

Bluefin tuna and chef Bluefin tuna - top of the food chain, and top of many people's eating lists

I'm not sure whether logically you can have such a thing as a footprint in water... but if you can, then the footprints of human fishermen now cover much more of the world's oceans than half a century ago.

In a WWF-commissioned report out this week, the spread is documented graphically.

The authors, based at the University of British Columbia in Canada, use the concept of "primary production required" (PPR) to illustrate the spread.

The idea is to calculate the proportion of primary production - all the chemical energy stored up in living things as a result of photosynthesis - that goes to meeting human needs.

The higher up the food chain you go to find the fish of interest, the more primary productivity you're using. The ones we tend to like eating best, be it tuna, cod or salmon, live at or near the top.

So at different points on the oceans and in different years, you get a variety of numbers, depending on how heavily they're being fished and what type of fish is being taken.

It's quite common now to find that humanity is taking 10%, 20%, even 30% of an area's primary productivity, the study calculates.

This isn't a precise measure of how destructive or sustainable the fishing is in a particular area - you might, for example, take virtually all of a valuable but rare species out of the water and end up with a low PPR value.

But when you read the report's calculations that the extent of ocean at 10% PPR has increased about 10-fold since 1950, that gives you some idea of how industrial fishing has spread across the world.

The spread is shown even more graphically in an animation produced along with the report, which shows nations sending ever bigger boats across the high seas to find fish in areas ever more remote from land.

WWF animation showing how fishing has expanded since 1950

Today there is barely an area untouched by fishing.

Regulation of fishing on the high seas has historically been done with the lightest of light touches.

With a few exceptions, the Regional Fisheries Management Organisations (RFMOs), formed of nation states with an interest in the given region, have done very little to stem unsustainable catches.

This is one of the issues that a number of environmental groups are desperate to move up the agenda of the Rio+20 meeting later this year, which could see overfishing being discussed by heads of state - a rare opportunity.

Damaged coral Coral reefs, like this one in Irish waters, can be severely damaged by bottom fishing

This push is backed by some European nations, though others are reportedly keen to keep fishing as low on the list of issues as possible.

Given the history of EU fisheries regulation, you might think the bloc is ill-placed to pose as a reformer.

But under its current fisheries commissioner, Maria Damanaki, the European Commission shows many signs of trying to put its historically dysfunctional house in order.

Shortly, it will publish proposals on regulating fishing for deep-sea species in the north-east Atlantic.

Parts of the area in question lies within territorial waters of EU nations, parts lie outside.

Biology doesn't see the boundary - and the commission is proposing therefore that the same regulations should apply inside and outside the demarcation line.

A draft of the proposals that has fallen into my possession shows the commission is explicit in its admission that so far, regulations haven't worked:

"The measures so far taken have not effectively solved the main problems of the fishery, namely:

  • the high vulnerability of these stocks to fishing
  • fishing with bottom trawls represents the highest risk of destroying irreplaceable and vulnerable marine ecosystems by fishing gear - the extent of destruction that has already occurred is unknown
  • fishing with trawls for deep-sea species involves high levels of undesired catch of deep-sea species
  • determining the sustainable level of fishing pressure via scientific advice is particularly difficult"

Among the new measures proposed are the phasing out of bottom trawls, the heavy gear that scrapes material from the bottom of the sea - fish, coral and anything else in its way.

In ecologically important areas, it's highly destructive.

Proponents point out that some areas of sea bottom are devoid of anything special and can stand it. The commission's argument is that too often, we don't know what is there before it is too late - and EU nations are committed to using the precautionary principle in such cases.

The commission also wants to see boats carrying independent scientific observers, and would be restricted to landing their catches in ports where inspection facilities are sophisticated enough to deal with the relatively unusual species involved.

Schematic of bottom-trawling

Environmental groups are of course urging the commission to go further. And a report this week from the Pew Environment Group shows that in one sense, regulating bottom fishing should be very easy.

These species make up only 2-4% of catches globally. They account for about 1.3% of the total value of EU fisheries.

A small economic cost in involved in restricting them, then, for a significant ecological gain.

As with her other proposals for fisheries reform, there's no guarantee Ms Damanaki will manage to get the agreement of the major southern European fishing nations.

And there's no guarantee world leaders in Rio will look at the scientific evidence on industrial fishing and conclude that maybe we really are reaching the end of the line.

But as WWF's animation shows, exploitation of the oceans' riches is now a global phenomenon, and has become so with incredible speed.

Richard Black Article written by Richard Black Richard Black Former environment correspondent

Farewell and thanks for reading

This is my last entry for this page - I'm leaving the BBC to work, initially, on ocean conservation issues.

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  • rate this

    Comment number 15.

    I'll be honest population is an area where there just doesn't seem to be any simple moral solution.
    Basically controlling things by controlling the birth rate introduces a large element of instability that is very dangerous.
    Killing is safer but amoral.
    - We need a new third way.

    It is also an issue where race and culture play an unpleasant role and are difficult to remove from the equation.

  • rate this

    Comment number 14.

    The problem with overpopulation is that it is not simple, population dynamics are very complicated mathematically and what is best for the overall population is often the worst for the individual.
    If we in the west are not careful we could face a population crash in the near future - because of birth control. But at the same time the overall population is pushing the limits of the ecosystem.

  • rate this

    Comment number 13.

    Rampant over-population and the insane drive to consume everything else on the planet makes the human race not only the environment's worst enemy, but our own. We MUST begin to live within our environmental means - and that includes curbing population growth and minimising our immediate and long-term ecological impact wherever and however we can. Only the selfish or foolish could say otherwise.

  • rate this

    Comment number 12.

    So there are plenty of fish then.

    Just considering the source...

  • rate this

    Comment number 11.

    "We need to talk about contraception, not tinker with fisheries rules."

    Perhaps we could do both and reap benefit on two fronts.

    I don't eat fish - we will soon have plastic filled fish, and plastic filled people:
    "Once the plastics had been eaten, it transferred from [the animals'] stomachs to their circulation system and actually accumulated in their cells,"

    We should also tinker elsewhere

  • rate this

    Comment number 10.

    Nothing really new here. Pretty much the same thing happened with whaling in the 19th century. What started off as local hunting ended with whale ships having to travel to the other side of the world on voyages lasting years. There are two underlying issues here; an apparent belief by some that the world's resources are inexhaustible combined with an inability to learn from history.

  • rate this

    Comment number 9.

    Over-fishing is one of the more obvious and less contentious results of overpopulation. Humans have reached plague proportions in parts of the planet.

    Our numbers have been growing exponentially for a century thanks largely to advances in medical and crop science, and medical science also offers a solution.

    We need to talk about contraception, not tinker with fisheries rules.

  • rate this

    Comment number 8.

    by-catch and discarded fish are also issues that needs to be resolved, and i do agree with RB on the trawling issue. Fishermen need to be involved to allow them to make a living in the least damaging way possible

  • rate this

    Comment number 7.

    Scientific sceptic
    That is the most idiotic thing I have read on these threads.
    Please spare us your stupidity

  • rate this

    Comment number 6.

    It might be better to look at halting the practice, such as in the EU, of cutting the quotas of one country only to let another fish the same area

    It's also worth noting that almost 1/4 of all the fish caught are turned into either animal feed or fetiliser

    How will fish stocks ever recover until we get to grips with some of the current excesses first?

  • rate this

    Comment number 5.

    Fish numbers are finite. Sooner or later mankind will sweep the seas clean of fish to feed our growing numbers. Of this there is no doubt.
    The planet will only recover after we have finished with it. We could try and regulate, but in the end the need for fodder will prevail. The sad thing is that intelligent life will, in the end, be replaced by turtles and sharks.

  • rate this

    Comment number 4.

    How many Grand Banks fishery collapses do there have to be before we start looking beyond the end of our dinner plate? As the Canadians have discovered, simply not fishing there hasn't restored the massive cod populations that used to swarm the area. Bottom trawling and overfishing has completely destroyed the ecosystem, as it will everywhere else unless we regulate effectively.

  • rate this

    Comment number 3.

    An example of the logic of the ‚Äúprecautionary principle‚ÄĚ at work:
    Disposable plastic cutlery in the environment might float down to Antarctica, be swallowed by juvenile penguins, get stuck in their throats, and choke them to death. Therefore it should be banned or regulated. Of course it might not do so, but it could, couldn't it? Just possibly? It might.

    So let's get regulating.

  • rate this

    Comment number 2.

    "The commission's argument is that too often, we don't know what is there before it is too late - and EU nations are committed to using the precautionary principle in such cases"

    -The problem with the "precautionary principle" is that there is always an unlimited number of things that may potentially be "bad". Legislation justified purely by ignorance strikes me as clinical insanity.

  • rate this

    Comment number 1.

    The thing, is Richard, you may well be telling the truth in this article, but after your reporting on Global Warming swindle anyone taking you seriously is doing so at their own peril.

    I am sure there are very real and urgent environmental problems to be solved and campaigned for, for example Shark fishing, but you Greens have blown it big time, and you have no reputation left...


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