CLEARFIELD -- Utah Division of Wildlife Resources officials now know what caused hundreds of birds to die in Clearfield a week before Christmas; however, there are still several unanswered questions.
Phil Douglass, the DWR conservation outreach manager for Northern Utah, said the toxicology results -- received Wednesday, from birds sent to a lab in Logan -- show the birds died after being exposed to Starlicide, a poison used primarily for starling population control.
"The thing that's tricky about the situation is there are two formulas of this Starlicide. One is commercial grade (used by the government) and the other is public grade, and there is no way of determining what grade it was," Douglass said. "So we know what it was, we just don't know where it came from."
Starlicide is a trade name for a chemical available to the public that is chemically similar to DRC-1339 -- a chemical salt -- used by Wildlife Services. The DRC-1339 is stronger than the Starlicide made available to the public in some states. Starlicide is not available to the pubic in Utah.
Douglass said Starlicide takes effect 24 hours after being administered.
"The one good thing about it is it's a relatively safe chemical," said Leslie McFarlane, DWR's wildlife disease program coordinator. "When a bird consumes (the Starlicide), it metabolizes fully in the bird's stomach. So if a dog eats the dead carcass, it won't have any effect on the dog."
Who administered the poison is still a mystery.
Clearfield officials cleaned up approximately 400 dead European starlings after the birds were discovered Dec. 18 in Kiwanis Park, 300 N. Vine St. While DWR investigated the deaths, no one took responsibility for poisoning the birds.
Mike Linnell, federal program director at Animal and Wildlife Damage Prevention Services, said his agency did not treat any birds in Clearfield.
Starlicide is not licensed for public use in Utah. However, there are ways for the public to obtain the chemical in other states in which the chemical is registered.
DWR officials can only speculate on whether someone bought the Starlicide out of state and then used it near Clearfield.
Douglass said, "That is just a possibility, but there is no way to substantiate that."
Adding to the mystery are 40 more dead European starlings that were found in Clinton on Wednesday. Douglass said these dead birds are exhibiting different symptoms than the ones found in Clearfield on Dec. 18.
"These (birds) had blood around their eyes and mouth," Douglass said. "We recommend that people don't handle them. And if they do, they should wear gloves and double-bag the carcasses and keep pets and children away."
DWR officials sent a few of those dead birds to the lab in Logan for a toxicology report. Because the people behind the bird deaths are unknown, DWR officials are concerned for other wildlife and public safety.
"While the starlings can overpopulate, and reductions are not a bad thing for starlings, what's causing that is a concern and we're trying to find that out," Douglass said.