One of the world's leading marine biologists has warned that we should stop eating tuna, shark, and swordfish in particular, not just for the sake of the ocean's health but our own as well.
Speaking at an international conference in
The former chief scientist with
Sylvia Earle spoke to our reporter Alison Caldwell in
SYLVIA EARLE: I began diving more than 50 years ago. In that time the ocean has really declined more perhaps than during all preceding human history as our capacity to enter the sea, to do things to the ocean that are unprecedented in terms of finding, capturing and marketing wildlife from the ocean.
Back in the fifties and sixties, there was a hope that we could extract as much as 100 million tonnes of wild creatures from the sea every year and the idea was that this would be the solution to the problem of world hunger. In fact we have discovered in this time, that the ocean has limits.
ALISON CALDWELL: Most people would think that, well, because we have marine protected areas, we have whale sanctuaries and the like, that things are actually getting better, that the health of the ocean is improving, but you say not really?
SYLVIA EARLE: In 50 years, through our actions we have seen a decline on the order of 90 per cent of the large predatory fish in the ocean. That means not just sharks, although sharks are in that category, but also tuna species, cod, swordfish, marlin. We can get away with taking some, but not on the scale that currently is undermining the basic processes that govern the way the world works.
We've seen the decline of coral reefs around the world partly because we've disrupted the basic functioning of those systems, taken away the predators, even taken away grazing species like manatees, like turtles, and more recently, like parrot fish and surgeon fish that once were not on anybody's menu except a few local areas, but today they're on the menu through the marketing expertise of Harrod's in London, it's just incredible.
Now the taste for the exotic is driving new pressures on the ocean, and while marine protected areas are a part of the solution, they must be coupled with over-arching understanding and policies that reflect the real limits of what the ocean can yield.
ALISON CALDWELL: Are you saying that people really shouldn't eat fish anymore? I mean, do you eat fish?
SYLVIA EARLE: I've eaten more than my share of fish over the years but in recent times I just know too much. For two reasons I have stopped eating fish and any other ocean wildlife, I just have. My brothers are shocked at the concept because they know that our family…
ALISON CALDWELL: …It's good for you…
SYLVIA EARLE: Well, it used to be, but I don't think that it is as good for us now as many people think because of what fish consume and concentrate, especially as you move up the food chain, you get concentrations on the order of 50,000 times of the very things you don't want in you.
Things such as mercury and the PCBs (poly chlorinated biphenyls), the materials that are in pesticides and herbicides that get concentrated through the food chain, and certainly one of the concerns is with mercury, that it's not easily expelled. It does concentrate in creatures such as sharks and tuna and swordfish.
It's mainly the high-end luxury market now that drives much of the fishing in the sea. It's not feeding the starving millions. It's feeding a luxury market. And having a system of critical areas that we recognise are important to protect the vital functioning of the ocean is a giant first step. Not the only step, but an important one that is good for the economy, it's good for the underpinnings of human health, for the security.
If we see declining condition of coastal areas let alone the high seas over the years to come, security is also going to be on the balance sheet. And when people are hungry because we've used up the productive capacity of the ocean that will lead, and is leading in many areas to poverty, which leads to problems relating to security. And it's just a cause and effect.
ELEANOR HALL: Marine biologist, Sylvia Earle, speaking to Alison Caldwell.
Source: Transcript from Radio