Northern bobwhite (Colinus virginianus) populations have experienced a general decline of an average rate of 3 percent per year across most of their range in the southeastern U.S. over the last 40?50 years. In Oklahoma in the western part of its distribution, populations have experienced a long-term decline, albeit at a lower rate than reported for other regions of the U.S. (i.e., 1.5 percent per year). In response to specific concerns over quail declines in western Oklahoma, the Oklahoma Department of Wildlife Conservation initiated a 6-year, multimillion-dollar project in 2011 through the Oklahoma Cooperative Fish and Wildlife Research Unit, the Department of Natural Resource Ecology and Management, and the Department of Entomology and Plant Pathology at Oklahoma State University. The overall objective is to determine the major factors driving long-term changes in bobwhite populations in western Oklahoma.

Loss and degradation of habitats have certainly played a significant role in the decline of quail populations throughout their distribution and in Oklahoma. Major problems are urbanization, large-scale agriculture, and, more recently, changes in landownership patterns. Fire suppression in Oklahoma has played a role in the loss and degradation of habitat by contributing to encroachment by eastern red cedar (Juniperus virginiana) and other woody species. Other factors such as weather catastrophes (e.g., persistent drought), predation, diseases (e.g., West Nile disease, avian influenza, and coccidiosis), contaminants (e.g., agrichemicals), toxins (e.g., aflatoxins), and global climate change also have been suggested as contributing to declines in local areas, and many of these factors may be interrelated with habitat changes. For example, widespread habitat changes across Oklahoma likely have altered aerial and terrestrial predator communities and habitat for disease vectors. Currently, our understanding of the role of these other factors in the decline of quail numbers is limited.

Associated with the decline in quail populations, there has been a decline in the number of quail hunters. In Oklahoma, the number has declined from 110,000 hunters in 1980 to < 30,000 today (Oklahoma Department of Wildlife Conservation, unpublished report). This decline in hunter numbers represents a substantial economic loss to the state in terms of revenues generated from license sales as well contributions to local economies from quail hunters. The decline of quail may also be an indicator that other species that rely on similar habitats are declining. The research undertaken by the Oklahoma Department of Wildlife Conservation and Oklahoma Cooperative Fish and Wildlife Research Unit was initiated to assess the many factors affecting quail populations. Six cooperating faculty members, one post-doc, nine graduate students, numerous field technicians, and Unit personnel are working on this project.

The Oklahoma quail research project has four major focal areas: 1) quail population and habitat studies (particularly focused on nesting and brood-rearing), historical perspectives on relationships between quail and weather, movement and survival of radio-marked adult quail and chicks, thermal modeling, refining methods of determining abundance, and vegetation monitoring relative to burning and grazing; 2) insect availability relative to nest-site choice, nesting success, and brood-rearing success with the goal of developing habitat-based predictive models of preferred insect and other invertebrate abundance relative to quail nest site selection and chick survival; 3) aerial and terrestrial predator studies focusing on the influence on usable space and GIS assessment; and 4) aflatoxins studies, particularly as they relate to the common use of supplemental grain in feeders for quail and other wildlife species. All research is being conducted on Packsaddle and Beaver River Wildlife Management Areas (WMAs), owned and managed by the Oklahoma Department of Wildlife Conservation.

Through November 2012, 782 bobwhites were captured, collectively, at the two WMAs, and 555 were marked with radio collars to monitor movements and document mortality. Apparent mortality was high in both areas with most mortalities being attributed to avian and mammalian predators. Persistent drought has occurred throughout Oklahoma during the past several years, with the western part of the state particularly affected. While the project is just in its beginning stages and few definitive results are available, it appears that drought has greatly affected bobwhites by reducing nest success and brood survival and altering available habitat and insect availability. It is anticipated that results from this research effort will enhance the management of habitats in western Oklahoma for bobwhites.

Each month, the ONB features articles from Cooperative Fish and Wildlife Research Units across the country. Working with key cooperators, including WMI, Units are leading exciting, new wildlife research projects that we believe our readers will appreciate reading about.