In the summer of 1987, two environmentalist organizations petitioned the Fish and Wildlife Service to list the northern spotted owl as an endangered species. After three years of litigation and negotiation, the matter comes to a head this month. The issue immediately affects only the Pacific Northwest, but it poses questions of national concern.

For the record: the spotted owl is a medium-sized owl, maybe a foot high, that dwells primarily in the old-growth forests of Washington, Oregon and Northern California. These forests are characterized by trees at least 200 years old. Over the past 150 years, owing to logging and to forest fires, the owl's natural habitat has been reduced by 60 percent.

There is no statistically reliable estimate of the remaining population. Wildlife biologists place the number of surviving pairs between 1,500 and 2,000. If the owl's habitat continues to disappear at the present rate, the species is headed for extinction in the foreseeable future. For that reason, the Fish and Wildlife Service last year recommended that the spotted owl be classified as a ''threatened'' species. By June 23 the service must decide if that recommendation should be formally approved.

In that event, the protective provisions of the Endangered Species Act of 1973 would be triggered. The Department of the Interior would have to suspend all logging on federal lands known to be the home of spotted owls. Indeed, no agency of government, federal or state, could take any action that would have adverse consequences for the species.

For a number of logging communities, especially in western Oregon, a ''threatened'' classification would have adverse consequences for another species: homo sapiens, man. It is a vast oversimplification to define the conflict in terms of the survival of 2,000 owls on the one hand or 25,000 jobs on the other, but politically the issue has become so polarized.

On May 20 President Bush was in Portland. There he spoke to a partisan fund-raising breakfast. He remarked that it will take a lot of work to protect the planet's wildlife ''without throwing hard-working citizens out of a job.'' He continued:

''I reject those who would ignore -- totally ignore the economic consequences of the spotted owl decision. {Applause}. The jobs of many thousands of Oregonians and whole communities are at stake. But I also think that we ought to reject those who don't recognize their obligation to protect our delicate ecosystem. Common sense tells us to find a needed balance. And together, I am convinced that we can work to find that balance.''

The subject came up again at a photo opportunity with Bob Williams, a Republican candidate for a House seat in Washington. The president reiterated his desire to find a balanced solution. He was interested in the spotted owl, ''very much so,'' but he was also interested in ''the human equation,'' in jobs and the American family. ''We've just simply got to find a way not to throw any of these people out of work.''

Now, if the president seriously meant that word ''any,'' the spotted owl is in trouble. Of greater importance, the Endangered Species Act itself is in trouble, for there is no way that a threatened or endangered species may be protected without some adverse consequences for ''the human equation.''

Is it possible to find a compromise that both loggers and environmentalists could live with? Prospects are not bright. On May 23 a Senate subcommittee reviewed a massive report that had been compiled by a blue-ribbon committee chaired by Jack Ward Thomas, chief research wildlife biologist of the Forest Service. The Thomas Report calls for creation of large habitat conservation areas in which logging would be prohibited.

Sens. Mark Hatfield of Oregon and Brock Adams of Washington straddled the issue: they came down unequivocally in favor of both the owl and the people. Sen. Malcolm Wallop of Wyoming was not so tactful. He ridiculed the Thomas Report as ''one of the most outrageous examples of the abuse of science and public policy I have ever seen.'' He found the recommendations ''utterly unacceptable to the American people, except for the hot-tub crowd with their special agenda.''

For the moment, there it stands. My own principal interest, as a conservative member of the hot-tub crowd, lies in preservation of the Endangered Species Act. It must not be sacrificed to the ''human equation.'' If the spotted owl goes, so goes the act. And over the long haul, to state the matter bluntly, the survival of the act is more important than the survival of the jobs.