Three aviary pathologists at Texas A&M University have independently concluded that parasites and a 10-degree drop in temperature were to blame for the deaths last week of 63 birds in Austin that briefly sparked fears of a public health threat, a scientist said Thursday.
"We eliminated our biggest concern: that there was a toxin or something that might be transmitted to humans," said Dr. Lelve G. Gayle, the executive director of the Texas Veterinary Medical Diagnostic Laboratory. "These birds were sick and stressed from parasites and then there was this sudden drop in temperature and that's what pushed them over the cliff."
The night the birds died, temperatures dropped from about 50 degrees to 40 degrees in six hours. The birds, which were mostly grackles, had parasites in their muscles, tissues and brains. None had food in their crops or gizzards, indicating they hadn't eaten in the previous 24 to 36 hours, Gayle said.
"We found no evidence that anyone should be concerned about a public health issue," Gayle said.
Police shut down a 10-block stretch of Congress Avenue in the heart of downtown Austin for several hours Jan. 8. The closure — on the eve of the state's 80th legislative session — came after the birds were found overnight along Congress between Sixth and Eighth streets. There were no reports of humans harmed.