Recently, several of the Noble Research Institute's wildlife staff traveled to Abilene, Texas, to attend the North Texas Quail Symposium: Preserving Texas' Quail Heritage into the 21st Century. It was an excellent meeting for those interested in quail management. There were several good "take-home" messages, some of which are summarized in this article.
Although quail populations in Texas have been declining in some areas and are relatively stable in others, the overall decline is slower than it has been in the southeastern United States, according to the North American Breeding Bird Surveys (BBS), and probably in Oklahoma as well. Quail numbers have declined the most in the East Texas Prairie and Edwards Plateau regions. Why is there less decline over most of Texas and perhaps Oklahoma versus the southeastern U.S.? Landscape changes caused by a change in land management practices and urban sprawl (habitat fragmentation) over time may be the culprits. Dr. Fred Guthery at Oklahoma State University suggests that many are managing "zombie" quail populations in "graveyard" habitats. In other words, small areas of usable habitat (graveyards) are created by urban sprawl and other detrimental land use. The quail (zombies) residing in these graveyard habitats are doomed to disappear because their population is too small for longevity.
A large part of the decline may be due to range management practices. For instance, overstocking livestock in areas suited to quail can be detrimental to the quality of quail habitat. Large-scale forb (a.k.a. weed) and brush control also can devastate quail habitat. Monocultural plantings such as introduced grass or pines destroy quail habitat. Dr. Dale Rollins at the Texas Agricultural Extension Service in San Angelo, Texas, stresses this point: know your plants, and know how to manipulate them.
Steve Nelle, with the Texas Natural Resources Conservation Service in San Angelo, presented a very good program reinforcing the validity of Dr. Rollins's statement. He reminded us of Aldo Leopold's central thesis of game management: game can be restored by the creative use of the same tools which have heretofore destroyed it-ax, plow, cow, fire, and gun. Know your plants. Quail managers should be able to identify the most preferred plants quail use for food and cover and should know how to manipulate them (abundance and distribution) with the ax, plow, cow, and fire. If food and cover are adequate and well distributed, weather may be the only factor limiting quail numbers from year to year.
For the "gun" portion of Aldo Leopold's equation, I refer to a program presented by Stephen DeMaso, an upland game biologist with the Oklahoma Department of Wildlife Conservation. He concluded that hunting is not compensatory (totally interchangeable with natural mortality), nor is it additive (cannot be added directly to it), and the effect of hunting on quail populations falls between the two. Remember, the longer into the hunting season a bird survives, the more likely it is to survive into breeding season. Therefore, birds killed in January are more likely to reduce the next season's breeding population than birds shot in November. He also added that individuals managing quail on private property can restrict harvest more than the state can by imposing limits such as number of hunters and days of hunting, bag, and method of hunting.
Now you are probably thinking that predators, fire ants, and similar threats, not just weather, may influence quail numbers. We listened to a lively debate on the subject. Dr. Rollins argued that predator control deserves serious consideration as a legitimate tool for quail management. To strengthen this point, Dr. Rollins referred to quails' behavior and anatomy adapting to the threat of predation. He agreed with predator control opponents who correctly espouse management practices result in higher densities of quail only when they increase usable space and that they are site- and time- specific. He further submitted that "prescribed predator control" does increase usable space in given situations, at least for a short period.
Dr. Nova Silvy of the Department of Wildlife and Fisheries at Texas A & M University argued that the ultimate factor affecting long-term quail numbers is habitat change at regional and national levels, with weather influencing yearly variation in local numbers. This hypothesis does not mean that predators cannot affect individual birds, coveys, or even a local population, but they are not responsible for long-term population decline at the regional or continental scale, nor do they cause large annual population fluctuations.
Dr. Brad Dabbert with the Department of Range, Wildlife, and Fisheries Management at Texas Tech University revealed that only 2 percent of bobwhite chicks in unprotected nests were killed by red imported fire ants (RIFA) in a field experiment his experiment team conducted. They found that survival rate of chicks in areas treated with insecticide was more than double that of chicks from untreated areas. They also found that chick survival rate is related to the density of RIFA as indexed by the number of RIFA captured within thirty minutes in a standardized bait cup placed in quail nests the day after hatch. When 300 or more RIFA are captured in the bait cup one day after chicks hatch, survival rate is zero. Conversely, when fewer than 300 RIFA are captured at the nest, chick survival rate is similar to that of chicks in treated areas. More research needs to be conducted on quail and RIFA interactions. Relationships of many variables such as weather, management practices, region, and quail and fire ant densities should be examined before conclusions are made.
Dr. Neal Wilkins, with the Texas Agricultural Extension Service, presented a program proposing that quail managers be concerned about aflatoxin poisoning. Simply stated, aflatoxin's effect on quail is largely unknown. In Texas, 300 million pounds of corn, the equivalent of two pounds per acre over the entire state, are fed annually to wildlife. He cited studies that demonstrated liver damage in deer after eight weeks on corn with aflatoxin levels of 800 parts per billion (ppb), mortality of mallard ducks consuming peanuts with 110 ppb, and liver damage and decreased immune capacity in turkeys consuming food with aflatoxin at 100 to 400 ppb. Aflatoxin poisoning's effect varies by species, age, concentration, and exposure rate. However, like turkeys and ducks, quail are probably more susceptible to aflatoxins than mammals such as deer. Furthermore, broken or stunted kernels of corn, which quail may be more likely to ingest, may have higher concentrations of aflatoxin.
In Texas, corn with an aflatoxin concentration higher than 20 ppb must have a warning on the label. Corn with concentrations above 100 ppb cannot be sold as deer feed. Dr. Wilkins was involved in a study that found bags of corn without a manufacturer's label were twice as likely to contain more than 100 ppb than labeled corn. There is no documentation of aflatoxin poisoning's reducing quail populations. However, a manager should feed only corn that has been tested and labeled to contain aflatoxin levels lower than 20 ppb.
So what is the bottom line? Manage for quail habitat; it is the single most important thing managers can do to help ensure the presence of quail and is something they can directly influence. We all should heed the statement Dr. Rollins made: "Know your plants and know how to manipulate them."