Life Cycle and Seasonal Influences on Bobwhite Quail Diet
By G. Ryan Shurette
courtesy of Wildlife Trends
As a young boy I was raised in the backwoods of Alabama, and like many of you I remember walking through open bluestem meadows, my dad nudging me up on a trembling pointer, with white knuckles gripping my .410, anticipating the jolting moment of the covey rise. When it finally happened we usually knocked down a couple, although not many fell as a result of my own shooting. The covey rise was fun indeed, but it seems my favorite thing to do when we got back and cleaned the birds (which was typically not many) was to go through each crop and gizzard to see what they’d been eating. Since my dad first showed me that trick, I made a habit of it and still seem to do the same thing today, even with doves and gobblers. The point is that by understanding food habits you can better understand the behavior and habitat requirements of the species you hunt and manage.
The changing seasons of the Southeast have over time led to a variety of different strategies among our native bird species for finding enough food to survive. Approximately half of the region’s birds deal with the stresses of a changing food base through some level of migration. However, the northern bobwhite, physically unable to make long distance journeys, is stuck here in the South and therefore must deal with the changing seasons as they come. Given its natural habitat and basic requirements, however, it survives.
The story of the bobwhite’s life in the world begins, of course, with pipping from the egg. Although it varies from year to year this commonly occurs around late June in the South. A new chick weighs only about ¼ ounce, and as soon as it is free from the shell and is dry, it is literally up and looking for food. A bird that is immediately mobile and able to forage for food is referred to as being precocial (as opposed to altricial, like bluebird and wren chicks, for example that require feeding by adults). There are tradeoffs for species between having precocial and altricial offspring, as the latter group generally has short incubation periods and thus can get off the nest quicker. During the first few days the chicks have imprinted to the tending adult bobwhite and are led about foraging for food; the frequently discussed process of brooding. While this phenomenon is indeed regularly discussed, the ecology of brooding among various habitats is still not fully understood, and brooding is often the limiting factor on quail populations (Burger 2001). During this stage, quality brood-rearing vegetation (structure and composition) is critical for chick survival. Small succulent insects and other arthropods are the name of the game in brooding. Larval grasshoppers (Orthoptera), leafhoppers and other true bugs (Hemiptera), and spiders (Araneae) make up a large portion of the young bobwhite chick’s diet. Other important foods during the first few weeks include aphids (Homoptera), beetles (Coleoptera), various flies (Diptera), caterpillars (Lepidoptera), and ants or bees (Hymenoptera) and terrestrial snails (Stylommatophora).
Figure 1.
Many studies have used human-imprinted bobwhite chicks as an index of assessing diet as well as brood habitat quality of an area (Palmer et. al. 2001, Smith and Burger 2005). A 2009 study by Burke et. al. examined the foraging of human-imprinted chicks in North-central Louisiana in various brooding habitat treatments. They noted that vegetation structure and conditions resulting from treatments of the herbicide imazapyr (Arsenal) and prescribed burning increased the ability of the chicks to obtain small arthropod prey. These management tools, as we know, set back succession and promote the growth of the correct mix of herbaceous plant species, structure, and bare ground (which is also essential to the maneuverability of young chicks). The correct structure of this brooding habitat makes all the difference in the world when it comes to survival of young chicks. A field study by Barnes et. al. in 1995 examined arthropod availability to chicks in fields dominated by tall fescue (Festuca arundinacea). Although there was a diverse and abundant arthropod prey base in the fields, the arthropods were not accessible to the chicks and therefore, it was concluded that fescue fields make relatively poor brooding habitat for quail.
Figure 2.
After about 6 weeks the bobwhite begins to incorporate non-arthropod food into the diet. At this time, it’s typically late summer and various species of berries, fruits, and seeds are ripe and available. The juvenile quail has been able to fly for a while now as well, and therefore has greatly increased its chances of survival. Summer crop and gizzard studies have indicated that fruits from blackberry (Rubus spp.), red mulberry (Morus sp.), blueberry and huckleberry (Vaccinium spp.), greenbrier (Smilax spp.), and poison ivy (Rhus sp.) are used as foods by juvenile quail. Although the high-protein insects are still taken when there is opportunity, green vegetable matter, flowers, and other plant parts also play an important role in wild bobwhite diet. There are also many species of herbaceous plants that have dropped their seeds by mid-summer as well. The seeds of foxtail (Setaria spp.) and many panic grasses (Panicum spp., Dicanthelium spp.) are often available by late summer, depending on soils and habitat conditions. If there is adequate bare ground and an abundant herbaceous plant community present, some amount of seed can almost certainly be scratched out.
Figure 3.
In autumn, seeds from various grasses are the main target food for a while, however they generally deteriorate fairly rapidly in the elements, and are later replaced in the quail’s diet by harder seeds. In a healthy, open, fire-maintained stand numerous species of these grasses, wild legumes, and forbs will predictably provide abundant fall quail food. However (as with arthropod availability in brooding habitats), the structure and composition of the understory often dictates how accessible these seeds are to juvenile and adult quail. If there is not enough bare ground for the quail to see and scratch out seeds, the resource will be largely unusable by quail. This can also be the case if the stand is infested with a sod-forming pasture grass or other exotic invasive species.
Acorns, when available, are also important to quail and are actually preferred by them in many situations. Seeds are generally lower in protein than are insects but some seeds are very nutritious. The seeds from the pea family (legumes) are extremely important in providing high protein food in fall and winter. They generally have a very hard seed coat that allows them to endure fires that periodically disturb their habitats, and so they must be processed in the quail’s gizzard. The gizzard is the critical part of a bird’s anatomy that (along with ingested gravel) breaks and grinds seeds and/or insect parts into a manageable form so that nutrients can be extracted. It is a strong involuntary muscle lined with thick sandpaper-like tissue called koilin, and it is the gizzard that makes it possible for the bobwhite to subsist on seeds in the dormant season.
As winter passes, the covey feeds almost exclusively on seeds of late-dropping plants and more persistent seeded species. Partridge pea (Chamaecrista spp.), beggarweeds (Desmodium spp.), doveweeds (Croton spp.), and tick-trefoils (Lespedeza spp.) are some of the most preferred, but some grasses are still commonly found in the crops of winter-harvested quail. During this time, the quail covey feeds together, usually near some form of tough woody cover like sumac, blackberry brambles, etc., to expedite their escape from potential predators. Feeding generally occurs early in the morning and again in the late afternoon. As the winter day draws to an end, the bobwhites huddle together in a roost circle to share body heat. Food is the generator of warmth on cold winter nights, and usually as long as the bobwhite is able to find food the day before, they will be able to generate enough heat to survive the elements. Several studies have shown quail can easily tolerate sub-freezing temperatures if nutritional needs are met. For this reason winter forage habitat, while it’s generally not the limiting factor, can’t be overlooked in a solid quail management program. Besides prescribed burning, timber management, and herbicide treatments, managers often employ supplemental plantings to ease the stress on a covey of finding enough quality seed on winter days. Countless varieties are used for this, but again, legumes or hard grains like milo and millet are ideal because they persist for longer periods of time and are often still available even into the spring.
With the spring, comes succulent green vegetation, and although seeds are still an important component, again they begin to be supplemented by insects as the weather warms. The high-protein arthropod diet is used also by adults (especially the hen), to prepare for the stresses of egg-production and incubation. Flowers, miscellaneous plant parts (including seeds), and arthropods constitute most of the springtime forage. By the time the chicks are hatched insect production is at its peak and if the structure of the vegetation is conducive to brooding, the process starts again.
In summary, the bobwhite is omnivorous species with dynamic habitat requirements. In order to successfully sustain a population these habitats must produce at the least, abundant arthropods and seeds. Although there is some variability and flexibility in the diet of the bobwhite, these basic needs must be met and be maintained in a structure that favors finding and obtaining these resources while also providing adequate protection from predators. Significant research efforts have been invested to learn how to predictably manage these habitats to supply the food items that maintain a bobwhite quail population through the changing seasons.
