Oceans Have Limited Capacity for Life

I've known for a long time that our oceans are in trouble. Forty years ago, it was assumed that when the human population grew a certain size, the 'enormous' resources of the ocean would be the thing that saved us. About ten years ago, I came across a map that showed the density of nutrients in the ocean and surprise, it's in the places where we already have famous fishing grounds. In the middle of the ocean, however, there are large, vast deserts that have life but not as much as we once thought. Part of it has to do with currents and prevailing winds and the life cycles of things like plankton and larger forms of microscopic life.

A study has come out and it's not good news about the fish populations of the world; here's the version I found in the San Jose Mercury News:

All of the world's fishing stocks will collapse before mid-century, devastating food supplies, if overfishing and other human impacts continue at their current pace, according to a global study to be published today by scientists in five countries.

Already, 29 percent of species that are fished -- including bluefin tuna, Atlantic cod, Alaskan king crab and Pacific salmon -- and an array of California fisheries have collapsed and the pace is accelerating, the report says.

If that trend continues, the study predicts that ``100 percent'' of fished species ``will collapse by the year 2048 or around that,'' said marine biologist Boris Worm, who led the research team. A fishery is considered collapsed if catches fall to 10 percent of historic highs.

Without more protection, the world's ocean ecosystems will not be able to rebound from the shrinking populations of so many fish and other sea creatures, the scientists reported in the journal Science.

What does all this mean? It means the carrying capacity of the earth is limited and humans are not helping matters with overfishing and pollution. It means we need to start thinking a little more carefully about the future and where we're going.