Land Use and Quail Population Biology

Local, regional, and national declines in abundances of the Northern Bobwhite have been observed in recent years. Results of the Breeding Bird Survey, for example, reveal for Illinois an estimated 2% annual decrease in quail numbers from 1966 to 1996. These local and regional trends suggest the value of taking a critical approach to the study of quail management. Long-term research has established much reliable information about the nesting, brooding, and overwintering requirements of quail; yet, as stated above, in many regions, recent declines have been drastic. A pervasive trend like this is unlikely to occur simply because management has not been sufficiently intensive; the level of expertise among upland game and quail biologists is high and support by the public has traditionally been strong.

Another pertinent trend is the increasing need to manage state lands with the goal of maximizing or conserving a wide spectrum of biodiversity. In the Midwest, this undertaking often involves ecosystem restoration and the introduction of periodic disturbance by some natural factor such as flooding or fire. Both prairie and savanna/woodland ecosystems are disturbance-mediated ecosystems; neither can persist without this disturbance. Jim Edgar Panther Creek State Fish and Wildlife Area (JEPC) in Cass County, IL, contains both of these endangered ecosystems among many others on a 16,550-acre site. Prescribed fire is being used to restore grasslands, rare hill prairies, and savannas/woodlands. Traditional quail management procedures are also in use on-site such as planting/rotation of appropriate crop species to provide nesting and brood cover in desirable proximity to other cover types. This site presents an excellent opportunity to study quail population biology on a multiple-use area.

Our research is conducted in collaboration with the Illinois Department of Natural Resources and JEPC. From 2000 to date, we have captured and leg banded 148 Northern Bobwhite, 93 of which have been fitted (Fig. 1) with radio collars.

We have found strong trends regarding habitat selection from the radiotelemetry data. Quail strongly prefer warm-season grass fields consisting primarily of warm-season grasses (Fig. 2) including big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), Indian grass (Sorghastrum nutans), and switch grass (Panicum virgatum). We determined this by comparing the amount of a particular habitat type in an animal's home range with the amount available on-site. Quail also show a weaker preference for areas with some cropland and forested cover. Quail show no preference or avoidance of areas of pasture characterized by a monoculture of tall fescue (Festuca arundinacea) and/or smooth brome (Bromus inermis), and cool-season grass fields consisting primarily of red top (Panicum rigidulum), Korean lespedeza (Lespedeza stipulacea), ladino clover (Trifolium repens), and Timothy (Phleum pratense).

Through quail telemetry and mark-recovery data, we have determined that our study population (age classes and sexes pooled) has an annual survival rate of approximately 20%. Survival seems to be most strongly affected during the winter months with winter storms having a dramatic impact on mortality. Mortality appears to be primarily due to avian and mammalian predators, with predation by avian species making up the bulk of these.

Our research is ongoing and these results represent just a fraction of our preliminary findings. In the future, we will examine long-term quail habitat selection trends on JEPC. We will contrast that with habitat use data from other suitable habitat islands in west- central Illinois. Using specialized radiotelemetry equipment, we will gather stress and energetics data from the quail during different phases of the year and life cycle, most notably during harsh winter conditions. We will also create a comprehensive demographic model of the Northern Bobwhite in west-central Illinois. Our research will give managers important insight into quail habitat needs, allowing them to improve the efficacy of current management practices.

Joseph Siegrist, UIUC and Jeff Brawn, Center for Wildlife Ecology

Please report any problems with or suggestions about this page to:
inhspubs@mail.inhs.uiuc.edu