November 23, 2009

Disease may play role in quail decline

By: Steve Byrns, 325-653-4576  
Contact(s): Dr. Dale Rollins, 325-653-4576,  
SAN ANGELO – Disease may be playing a role in the demise of Texas quail, said a Texas AgriLife Extension Service expert.

“Quail season has been disappointing,” said Dr. Dale Rollins, AgriLife Extension wildlife specialist at San Angelo. “By Texas standards, wild quail hunting has been sub-par since 2006, and I’m wondering if disease might not be part of the puzzle. Certainly, it’s probably not the key reason, but I’m starting to suspect it may be a contributing factor.”

Rollins said coccidiosis (malady caused by parasitic protozoans of the digestive system) is often blamed, but exactly what disease might be behind the drop in quail populations, or even if there is a disease contributing to the problem, is currently unknown. He said there are other potential threats, including West Nile Virus, avian influenza, avian cholera and avian tuberculosis that may be factors.

Sick quail don’t last long before something eats them, so disease surveillance in wild quail is a tough proposition, according to Rollins.

“I’ve always been intrigued by the possible role disease plays in quail dynamics,” Rollins said. “When you think about it, the birds offer a perfect biological fuse for disease spread among the population. They are social birds, and when a covey dwindles to less than about six birds, they go join another covey.

“Blue quail used to be common over areas as far east as Throckmorton, but they disappeared over much of their range in 1988; December 1988 to be exact in my opinion. While hunting in Crockett County that December, I dressed several birds with spotted livers, but didn’t think much of it. I just took some photographs and discarded the birds. Within months, blue quail had vanished as far west as the Pecos River. I can’t explain such a die-off except by some mystery disease. Suffice it to say my antennae are up for sick quail now.”

Rollins asks quail hunters to be on the lookout for sick quail this season. If birds taken are too light for their size or if a green discharge from the vent is spotted, he said it would be worth noting. He said to pay special attention to whether the liver has white or yellow nodules in it which are signs of a bacterial infection.

If disease is suspected, Rollins asks hunters to place the bird in a plastic zipper-type bag, refrigerate it and call him as soon as possible at 325-653-4576 or 325-776-2615.

Rollins is also the director of the 4,700-acre Rolling Plains Quail Research Ranch at Roby. He said they are currently live-trapping quail at the ranch for leg-banding to support a radio telemetry project. At the same time, they also are collecting samples for disease and parasite testing.

“We’ll submit about 200 samples for screening of viral, bacterial and parasitic diseases,” he said. “These data will help us better understand whether various diseases really are a factor.

“A separate research project on eye worms and intestinal parasites was started in September in collaboration with the Caesar Kleberg Wildlife Research Institute. Preliminary testing from quail collected on the research ranch last winter showed parasite infestation in the eyes, which may be noteworthy. When you’re a bobwhite, you live on the edge as it is; any debilitating factor like worms under your eyelids can’t be good.

“At the research ranch, we’re seeking to unravel just what’s happened to bobwhites and blue quail across much of the Rolling Plains,” he said. “We’ve adopted a philosophy of ‘leave no stone unturned.’ So, we’re investigating some heretofore overlooked agents, namely disease and parasites to see if they possibly are playing a more than minor role in the demise of Texas quail.”