ARUN RATH, HOST:
Hundreds of dead and wounded seabirds mysteriously appeared off the coast of San Francisco earlier this year all coated in a sticky, gray substance that was eating away at their feathers. Lindsey Hoshaw of member station KQED reports on the challenges of finding out what the mystery goo is and who dumped it.
LINDSEY HOSHAW: In mid-January, hundreds of seabirds began washing ashore with matted feathers that were destroyed by an unidentifiable gunk. State scientists have been analyzing the goo-coated feathers, running a series of tests at the investigation's headquarters near Sacramento.
GAIL CHO: OK, so we're walking into the pesticides instrument lab, and we're surrounded by metal boxes with displays. They look a little bit like a microwave oven but with a lot more buttons.
HOSHAW: Chemist Gail Cho is with the California Department of Fish and Wildlife. She says trying to identify the substance without any starting point is a nearly impossible task.
CHO: You're basically trying to reconstruct a vase from a pile of powder.
HOSHAW: On crime scene dramas like CSI, the process can seem simple and take less than a day.
(SOUNDBITE OF TV SHOW, "CSI")
UNIDENTIFIED ACTOR: So we just got to get this to the DNA lab, have them confirm it is our victim's blood, and then case closed.
HOSHAW: But Cho says that's not how it works in real life.
CHO: A typical CSI show takes about 40 minutes minus the commercials. A typical run for analyzing one compound like polychlorobiphenyl takes almost an hour - for one of them.
HOSHAW: Polychlorinated biphenyl, or PCB, is a chemical used in paint, pesticides and plastics. Analyzing every variety of PCB would take more than a week for each one, and there are thousands of suspects, thousands of chemicals to analyze. Another big problem is you don't have a motive. Jay Green is Special Agent in Charge for the Environmental Protection Agency's criminal investigation division. He says the EPA can't simply go pointing fingers until the scientists can figure out what this stuff is.
JAY GREEN: Many murders, as a detective, you go into it knowing - you already know who the assailant was because they were found at the scene or you got information from the victim before he or she passed.
HOSHAW: The investigation into the spilled goo is taking so long that most of the surviving seabirds have been scrubbed clean and released already. The birds were set free on the shore of Fort Baker, just north of San Francisco. Barbara Callahan, Executive Director of the International Bird Rescue Center, helped haul them down to the beach in colorful boxes. The birds rattled from inside.
BARBARA CALLAHAN: It's amazing to watch birds like this go back to the wild. Like, this is a beautiful male surf scoter and he will fly right out as soon as we open that and show him the water.
HOSHAW: The EPA has recently opened a tip line and is hoping the public can offer clues as to what the mystery goo really is. For NPR News, I'm Lindsey Hoshaw in San Francisco. Transcript provided by NPR, Copyright NPR.