I want to make some simple points about what we humans are doing to life in the oceans, but since simple points apparently take a long time to sink in, I am going to make those points today and over the next two days. Even then, I don't expect many people to get it, to fully understand that the long-term consequences of what I'm saying here, but there's no harm in trying.
Simply stated, humankind is destroying animal life in the oceans through overfishing and other environmental insults. The trend is so dire that it is unlikely there will be any wild fish in the oceans by 2050. In the middle age of children being born now, the oceans will likely be devoid of edible creatures (fish, mollusks, crustaceans, and so on). If we had some reason to believe this trend could be reversed, we could embrace the obligatory Hope. But there is currently no reason to believe this destructive trend will be reversed.
Writing in the New Yorker, Elizabeth Kolbert asked is there any hope for our overfished oceans? Her article The Scales Fall (August, 2010) makes it clear that early estimates of the sea's bounty were a tad on the optimistic side. The first scientist to take a crack at estimating the ocean's riches was Thomas Huxley.
Thomas Huxley, who is now mostly remembered for being an early supporter of Charles Darwin, was at the time the president of Britain’s Royal Society, and he delivered the exhibition’s opening address. As his topic, Huxley chose the question “Are fisheries exhaustible? That is to say, can all the fish which naturally inhabit a given area be extirpated by the agency of man?” The answer, Huxley decided, was a qualified no. Although people might be able to wipe out the salmon in a certain stream by throwing a net across it “in such a manner as to catch every salmon that tries to go up and every smolt that tries to go down,” conditions in the ocean were altogether different.
“Probably all the great sea fisheries are inexhaustible; that is to say that nothing we do seriously affects the number of the fish,” Huxley declared...
Huxley’s views dominated thinking about fisheries for most of the next century...
Estimates got entirely out of hand in the prosperous post-World War II years. The belief in endless growth (including in natural resources) took on most of the characteristics of a faith-based religion. Wishful thinking abounded. Words like "inexhaustible" and "limitless" were bandied about.
In 1955, Francis Minot, the director of the Marine and Fisheries Engineering Research Institute, in Woods Hole, Massachusetts, co-wrote a book titled “The Inexhaustible Sea.” As yet, he observed, “we do not know the ocean well enough. Much must still be learned. Nevertheless, we are already beginning to understand that what it has to offer extends beyond the limits of our imagination.”
In 1964, the annual global catch totaled around fifty million tons; a U.S. Interior Department report from that year predicted that it could be “increased at least tenfold without endangering aquatic stocks.”
Three years later, the department revised its estimate; the catch could be increased not by a factor of ten but by a factor of forty, to two billion tons a year. This, it noted, would be enough to feed the world’s population ten times over. Michael L. Weber observes, in “From Abundance to Scarcity” (2002), that as recently as the nineteen-nineties U.S. policy was predicated “on the belief that the ocean’s productivity was almost limitless.”
The "experts" obviously got pretty giddy in making these estimates, but the real world is a different matter. Kolbert briefly describes how technological advances drove higher fish landings over time. And then in the late 1980s, we hit the wall.
In the short term, the new technology worked, much as Huxley had predicted, to swell catches. But only in the short term. In the late nineteen-eighties, the total world catch topped out at around eighty-five million tons, which is to say, roughly 1.9 billion tons short of the Interior Department’s most lunatic estimate.
This milestone—the point of what might be called “peak fish”—was passed without anyone’s quite realizing it, owing to inflated catch figures from the Chinese. (These fishy figures were later exposed as politically motivated fabrications.) For the past two decades, the global catch has been steadily declining. It is estimated that the total take is dropping by around five hundred thousand tons a year.
In Systematic distortions in world fisheries catch trends, which was published in the journal Nature in 2001, Reg Watson and Daniel Pauly demonstrated that the Chinese had routinely exaggerated their fish catch to the upside after the peak had been reached. They also documented the effects of El Nino events on Peruvian anchoveta (anchovy) landings.
Looking at a "peak fish" graph, one has to be careful to see whether the Chinese distortions have been included. In the first graph below, which goes up to 2002, the exaggerations have been highlighted. In the second graph, based on FAO data, it appears that the distortions have been retained.
Includes aquaculture (fish farming), which will be discussed separately. Source
Kolbert briefly explores the tragic consequences of overfishing.
Meanwhile, as the size of the catch has fallen, so, too, has the size of the creatures being caught. This phenomenon, which has become known as “fishing down the food web,” was first identified by Daniel Pauly, a fisheries biologist at the University of British Columbia. In “Five Easy Pieces: How Fishing Impacts Marine Ecosystems” (Island Press; $50), Pauly follows this trend to its logical—or, if you prefer, illogical—conclusion.
Eventually, all that will be left in the oceans are organisms that people won’t, or can’t, consume, like sea slugs and toxic algae. It’s been argued that humans have become such a dominant force on the planet that we’ve ushered in a new geological epoch.
Pauly proposes that this new epoch be called the Myxocene, from the Greek muxa, meaning “slime.”
The Myxocene — The Age Of Slime. The world's oceans will be devoid of edible creatures. Chew on that.
Finally, if you consider the lack of fish a non-problem because marine animals are a "renewable" resource, think again. There are two possible outcomes for an overfished marine animal: 1) the species will fall below its minimal viable population, and will thus be on the road to extinction; or 2) the collapsed population will come back, but only very slowly over many tens or hundreds or thousands of years. In this latter case, the resource is indeed renewable. People will just have to sit around & wait that long to get food from the sea once again
Tomorrow we will look at the fate of bluefin tuna. Previous posts on related subjects include:
How We Wrecked The Oceans — Part II
There are so many indicators of man's influence on the degradation of the planet- overfishing being one- that I sometimes wish we would lessen our focus on global warming and focus on the more concrete, easy to measure unarguable effects. In Republican logic, the case goes that if we can't positively prove that mankind is causing global warming, then we are not ruining our environment. There is so much else- decline of fisheries, desertification, depletion of aquifers, soil loss; that there shouldn't be an argument.
Posted by: John D | 06/12/2011 at 10:10 AM