A preliminary study has found no genetic variation between a California owl and the northern spotted owl, whose dwindling numbers and steady loss of habitat have put it at the center of a dispute concerning logging in the Pacific Northwest.
The results raise the question of whether the two birds are one subspecies of spotted owl rather than two, as scientists have thought.
But researchers said they had analyzed only a small portion of the birds' genes so far. Further investigation and the use of more powerful analytical tools might turn up genetic differences, they said.
If ultimately borne out, the preliminary findings could intensify the fierce argument in the Northwest, where the northern spotted owl has been declared a threatened subspecies.
Federal scientists say it is dying out because of heavy logging in the ancient, old-growth forests that provide its habitat. Over the strong and sometimes bitter opposition of lumber interests, the Fish and Wildlife Service has adopted a plan to protect the bird by limiting logging.