Satellites, for better or worse, have had an enormous impact on our oceans. Sadly for the fish, the impact has been mostly for the worse. A new study published in the journal Science finds that the most abundant ocean fishing regions today contain just five species on average, compared with 10 species 50 years ago. The hot spots, in other words, are growing cold, and soon may be indistinguishable from the rest of the open seas.

The main culprit is not environmental, it’s overfishing. And satellite images are the weapon of choice for fishing fleets, which can now more quickly and cheaply find where the most fish are.

“OrbMap software allows captains and fleet managers to easily translate advanced satellite data into successful fishing decisions,” boasts a Web site for Dulles, Va.-based Orbimage Inc., a leading satellite image provider to commercial fishers.

This kind of “remote sensing” was hardly envisioned when the first communications satellites went into orbit in the early 1960s. Yes, spy satellites could zoom in on large land objects (such as missiles in Cuba). But over the past two decades, advances in imaging and computing began allowing satellites to track such details as ocean plankton levels, temperature, currents and depths — even filtering out atmospheric interference.

Yes, other factors contribute to the depletion of ocean fishing stocks, including pollution, worldwide government fishing subsidies and a growing global population. But overfishing is the primary cause, as supertrawlers — guided by satellite data, sonar and spotter planes — gain ever-increasing yields by dragging over the hot spots with enormous nets or long fishing lines with hundreds of hooks.

Satellites are also being used to identify and prevent exhaustion of fish stocks, of course. Poring over 16,000 satellite photographs, nearly 1,400 scientists from 95 nations recently echoed the concerns of the Science study by concluding in their “Millennium Ecosystem Assessment” that overfishing, combined with coastal pollution, has put the world’s oceans in peril.

A year ago this week, the U.S. Commission on Ocean Policy, a panel ordered by Congress and created by President Bush, called for a five-year plan to double ocean science funding, which it said had fallen from 7 percent of the total federal research budget 25 years ago to just 3.5 percent today. A key panel recommendation was the creation of an “integrated ocean observing system” to collect water, air and spaced-based data not only to track fish populations, but to improve hurricane and tsunami warnings.

The commission proposed boosting funding for ocean science from $2 billion annually to $3.5 billion in fiscal 2006. The Bush administration praised the findings last December, but in February proposed cutting funding for ocean and coastal programs at the National Oceanic and Atmospheric Administration (NOAA) by more than $391 million. Last week, the Senate passed its version of the Commerce-Justice-Science appropriations bill, which includes an additional $666 million to carry out commission recommendations.

Of course, it’s much easier to use satellites to catch fish than it is to protect them. Satellite images may show where fish recovery needs to take place, but the real trick is to set limits and enforce them. That is often hard to do, considering that most of the big fishing nations, including the United States, give the industry more influence over policy-making than the scientists get.

In the United States, NOAA delegates limit-setting to eight regional councils, composed mainly of industry representatives. And the agency is proposing a rules change (comments are due Oct. 21) that would give those councils greater flexibility in setting and complying with limits on commercial fishing. Supporters say that would allow the councils to more precisely decide which species need protection, but conservationists call the plan irresponsible at a time when 20 percent of the nation’s major marine fish stocks are overfished. The issue will dominate an upcoming effort to reauthorize the underlying Magnuson-Stevens fisheries law.

The Ocean Policy commission wants to overhaul the membership of the regional councils. “Their credentials and potential conflicts of interest should be vetted by an external organization,” its report says, and councils should be “required to rely on the peer-reviewed advice” of their own scientific committees when setting harvest levels.

The panel also recommends a new White House office to coordinate ocean policy. Today, that responsibility crosses 11 federal agencies, with the Commerce Department’s NOAA taking the lead. But NOAA, as is often pointed out, has a conflicted dual mission of promoting commercial fishing and protecting ocean ecosystems.

NOAA’s broad uses for satellites illustrates the conflict. One part of its Web site offers satellite and mapping data to help boats find where the most fish are biting — while elsewhere NOAA trumpets its use of satellite-based images and vessel-location monitors that protect the hot spots. The future of the seas, it seems, is being decided in space.

Mike Mills is CQ’s executive editor for electronic publishing. Next week’s CQ Roundtable: Courts & the Law, by Kenneth Jost.