Bobwhite and the New Biology

Phrases and concepts familiar to traditional wildlife managers like carrying capacity, annual surplus, and edge are being replaced in the literature and at conferences by terms such as biodiversity, metapopulations, and fragmentation. I raise the question of whether this new vocabulary merely represents trendy buzzwords of the 1980\u27s, or is it relevant to bobwhite management in the 1990\u27s and beyond? Some aspects of the “new” biology appear to differ from traditional wildlife management primarily with respect to scale, and may therefore be applicable in dealing with relatively isolated populations in dissected habitats. Others, however, reflect more basic differences in philosophies and agendas. Implications for future bobwhite management are discussed

Sustained Harvest of Bobwhite Populations

(Invited Paper) Sport hunting is an important aspect of wildlife management, yet the principles of game harvesting seem not to be particularly well understood or accepted by many in the wildlife profession. This paper examines the two major harvest theories as they apply to the bobwhite. The sustained yield approach is considered conceptually superior to the popular annual surplus theory. Wildlife management admittedly involves practical as well as theoretical considerations; nevertheless, it is important that harvest policy be based on sound scientific principles and guided by clear objectives. To do otherwise puts both the resource and our own professional credibility at risk

Contribution of CRP to Illinois Bobwhite Habitat at the Landscape Level (Poster Abstract)

Northern bobwhite (Colinus virginianus) population declines in the midwest have been attributed to habitat degradation and loss due mainly to intensified agricultural land use and farming practices. Thus, there was initial optimism that the Conservation Reserve Program (CRP) would benefit bobwhites by converting cropland to semi-permanent grassland. However, CRP apparently has not positively impacted regional or statewide population trends in Illinois. Deficiencies at both site and landscape level may be involved. To address the latter issue, we mapped the location of each individual CRP field (\u3e 8,800) in 11 representative counties within the bobwhite range in Illinois. We then analyzed their spatial relationship to other land cover and bobwhite habitat using Geographic Information Systems and a statewide digital land cover map based on classified satellite imagery. Existing bobwhite habitat and CRP fields tended to be spatially correlated because both are largely confined to moderately rolling terrain as opposed to very hilly or very flat areas. Nevertheless, almost 25% of all existing CRP acreage within our 11 study counties occurred in landscapes with insufficient woody edge to support high bobwhite populations. Furthermore, CRP did not always provide the habitat component most limiting for bobwhites

Some Aspects of the Dynamics of a Hunted Bobwhite Population

Dynamics of a hunted bobwhite population have been investigated on a 1,450-acre study area near Carbondale, Illinois since 1952. Habitat conditions have not changed greatly during the study, and November densities have oscillated regularly about a rather stable long-term mean. Most of the variance of annual rates of population change is due to variation in net productivity from spring to fall rather than to variation in net losses from fall to spring. Population declines from November to April averaged 66% (range 36 to 81%); about 0.66 of this resulted from hunting. Post-hunting mortality, which was slightly density-related, partially compensated for hunting losses. Spring densities were correlated with (r = +o.75) and almost as variable as preceding fall populations. Net increases from spring to fall varied from 17 to 383 and averaged 235% of the breeding population. Multiple regression analysis showed that annual rates of productivity were significantly influenced by the combined effect of breeding density, length of snow cover during the previous 2 winters, and amounts of prenesting rainfall. Annual rates of population change were inversely related to the preceding fall density, but strong correlations between successive seasonal population levels caused periods of change as well as highs and lows to persist for several years. Major highs and lows each occurred at 8- to 10-year intervals. It was not clear whether 2 severe winters caused the apparent cyclic regularity or merely accentuated the lows

Attitudes of a Select Group of Illinois Quail Hunters

During the past 3-4 decades major social, political, economic, and environmental changes have taken place in the United States that have greatly affected quail hunters, their quarry, and their sport. Against this backdrop, we examined the attitudes and perceptions of a select group of Illinois quail hunters from 1954 to 1989 regarding issues such as stocking, predator control, habitat management, and harvest regulations. During this time, hunters became increasingly cognizant of the importance of habitat and less inclined to demand unproductive practices such as stocking. Concerns about predators peaked in the 1970\u27s. Hunters in the I980\u27s tended to want more liberal hunting seasons than did their predecessors. Possible explanations and implications of these trends are discussed

Cyclicity in Northern Bobwhites: A Time-Analytic Review of the Evidence

Cyclical behavior in wildlife populations, including northern bobwhite (Colinus virginianus), has long fascinated human observers. However, studies examining cyclicity of bobwhite abundance have yielded contradictory results. We reviewed evidence for periodic fluctuation in bobwhite abundance by studying 73 long-term time series. Our aim was to discern with time-series techniques whether cyclicity occurred in bobwhite abundance. We elucidated the frequency of occurrence, geographical distribution, and potential mechanisms responsible for cyclicity. Approximately one-half (n = 37) of the populations examined demonstrated cyclical behavior, with a period varying between 4 and 17 yrs. True cycles, consistent, significant fluctuations in abundance, were rare, occurring in only 3 time series. The predominant form of periodicity was of the phase-forgetting quasi-cycle type (n = 34). This phase-forgetting may have contributed to previous contradictory findings of cyclicity in this species. We reason cyclicity in bobwhite populations is caused by aperiodic environmental perturbations interacting with density-dependence. Cyclic bobwhite populations occupied the northern and western portion of the species’ range, where stochastic weather events regularly negatively influence bobwhite population dynamics. Bobwhite populations were non-cyclic in the relatively consistent climate of the southeastern United States, however, habitat fragmentation rather than climate may have contributed to the absence of cyclicity in this region