A new view of the gnatcatcher ENVIRONMENT: DNA tests change the perception that there is a specific California subspecies.
September 27, 2000
By JIM RADCLIFFE
and TIFFANY MONTGOMERY
The Orange County Register
For years, scientists have assumed that it was a unique branch of the California gnatcatcher family that nested in coastal sage scrub from Palos Verdes to Ensenada. That subspecies was deemed threatened by the U.S. Fish and Wildlife Service, which is due to announce new regulations to protect the bird's habitat in Southern California by Monday.
But a new study based on DNA testing has concluded that there might not be a separate subspecies of California gnatcatchers after all.
"You can't tell a gnatcatcher from Palos Verdes from one from Cabo San Lucas," said Robert Zink of the University of Minnesota, whose researchers performed genetic testing on 64 birds in 13 locations in Mexico and California.
Ironically, one of Zink's co-authors, Jonathan L. Atwood, was critical in obtaining federal protection for the California gnatcatcher subspecies in the first place.
Originally, it had been assumed that if a gnatcatcher in Palos Verdes was a different color than one in Ensenada, there was a genetic difference between them.
But modern DNA techniques have changed some of those assumptions, Atwood said in an e-mail.
"In 10 or 20 years, new techniques may, yet again, require a revision of this conclusion," he said.
The results of the study could impact a ruling expected this week by the Fish and Wildlife Service -- a ruling that would most likely be welcomed by environmentalists and loathed by developers.
The decision was expected to designate 800,000 acres of land in Southern California -- 97,000 acres in Orange County -- critical for the survival of the gnatcatcher subspecies.
Although there may not be a unique subspecies of California gnatcatcher after all, it does not mean that regular California gnatcatchers in Southern California are not threatened, as the Fish and Wildlife Service has declared, Zink said.
While gnatcatchers are fairly common south of Ensenada, their populations are sparse in Southern California because more than 90 percent of their habitat, coastal sage scrub, has been destroyed, Zink said. And because the songbirds are not migratory, large flocks from Mexico will not relocate across the border.
"If (gnatcatchers) disappear from California, they will disappear from the United States," he said.
The study, which cost roughly $100,000, was funded by private, public and academic bodies. Sponsors ranged from the National Fish and Wildlife Foundation and Southern California Edison to the Manomet Center for Conservation Sciences and the Building Industry Association of Southern California. Zink said none of the study's sponsors had any input in the research.
The sudden change in opinion in some scientific circles is welcome and overdue, said Irvine land-use attorney Rob Thornton, who challenged Atwood's original conclusion about the California gnatcatcher subspecies.
"I feel extremely vindicated," said Thornton, who expects some in the development industry to sue if the Fish and Wildlife Service does not postpone its ruling.
"They should not make this enormous regulatory decision on the basis of a species that should never have been listed in the first place."
Douglas Krofta, a biologist for the Fish and Wildlife Service who is authoring the final ruling, said department officials are reviewing Zink's study, which will be published in the October issue of the journal Conservation Biology.
Register staff writer
Jose Flores contributed to this report.
