The oceans are dying. A recent report by an international team of researchers, in the journal Science, predicts that our planet has “‘Only 50 years left’ for sea fish.”

Now, after 30 or more years of environmental catastrophism, a little skepticism may be in order.

But take a step back: The biggest failures of environmentalist prediction in the past have been over world population and poverty. In the ’60s and ’70s, quite a few environmentalists predicted mass starvation by the ’80s and ’90s. Didn’t happen.

Why? Because most of our food comes from farms. Which are private property, for the most part. Which depend on markets. And markets have pretty good feedback systems, allowing for progress.

But the seas? There’s scant “private ownership of the means of production” in the oceans. Fisheries basically just harvest nature’s bounty.

Which leads to OVERKILL. Just as common ownership of farmland led to what’s called “the tragedy of the commons” — private over-grazing of commonly held fields — common ownership, or downright non-ownership, of ocean beds and waters can’t help but lead to over-fishing.

Steve Palumbi, a Stanford researcher, claims that “this century is the last century of wild seafood.” We must “fundamentally change the way we manage” the oceans, he says.

Scientists may very well be right that large no-fishing zones should be established. But if we don’t also establish workable private enterprise in the oceans, these warnings will be like Cassandra’s: futile.

This is Common Sense. I’m Paul Jacob.