Broad-Scale Population Declines in Four Species of North American Quail: an Examination of Possible Causes Leonard A

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Broad-Scale Population Declines in Four Species of North American Quail: An Examination of Possible Causes Leonard A. Brennan 1

Abstract - Christmas Bird Count (CBC) data from 1960-1989 indicate that California quail (Cal/ipepla califomica) , northern bobwhite (Colinus virginian us) , and scaled quail (Callipepla squamata) populations have experienced significant declines in major portions of their geographic ranges. Additionally, surveys and hunter bag returns during the past 50 years indicate that mountain quail (Oreortyx pictus) populations have eXperienced 2 a series of local extinctions across broad areas (several thousand km ) in Idaho and Nevada. Although changing land uses can be related to these declines, no single factor can be linked to all species. For northern bobwhites, clean farming methods in agricultural environments and intensive, high-density pine-dominated silviculture seem to be the two major reasons for broad-scale population declines, especially in the southeastern states.

For mountain quail, regional extinctions in Idaho and Nevada are apparently related to two factors: (1) intensive agriculture and associated hydro-power reservoir impoundments along the Snake River corridor, and (2) disruption of key habitat resources along secondary riparian corridors by excessive cattle grazing. Factors responsible for declines in California quail and scaled quail populations are at present unknown, but are apparently related to abuses associated with excessive grazing of western rangelands. Management strategies that can be used to sustain quail populations in wildland environments are summarized in an ecological context.

INTRODUCTION agriculture and forestIy have, however, called into question what were once symbiotic relationships between people, quail, Historically, populations of New World quail farming and forestIy. (Odontophorinae) have been considered a sustainable by-product During the past decade, reports indicated that northern of many agricultural and silvicultural activities (Stoddard 1931, bobwhite populations (Colinus virginian us) had declined at Leopold 1933, Rosene 1969, Leopold et al. 1981). many locations (Rosebeny and Klimstra 1984, Droege and Abundant quail populations in rural and wildland Sauer 1990). TIlls downward trend of one of the most common environments improved the quality of life for people by and widely distributed game birds in North America surprised providing recreational opportunities, economic returns from many people. Further analyses revealed that northern bobwhites leasing lands for hunting, and other positive social values that had indeed declined on both continental, regional and statewide resulted from a consumptive connection with wild vertebrate scales (Brennan 1991, Brennan and Jacobson 1992). resources (Leopold 1933). Changing patterns of land use in The extent and magnitude of the bobwhite decline resulted in a Strategic Planning Workshop for Quail Management and 1 Leonard A. Brennan is Director of Research, Tall Timbers Research in the United States that was held at the Third National Research Station, located in Tallahassee, FL. Quail Symposium in 1992 (Brennan 1993a, 1993b). This woIkshop was the ftrst attempt to develop a comprehensive

44 strategy for quail management and research in the United States. Independent analyses of Breeding Bird SUlVey (BBS) data It followed a regional strategic planning effort for upland game collected by the U.S. Fish and Wildlife SelVice (Sauer et aI. birds that was developed for western states by the Bureau of 1993) corroborated the patterns shown by the CBC data. Land Management (Sands and Smurthwaite 1992). Although the mountain quail (Oreortyx pictus) showed no My objectives in this paper are to (1) summarize long-tenn evidence of decline based on CBC data (Figure 1), game trends of quail populations at the continental scale in the United biologist sUlVeys, hunter bag returns, and comprehensive field States and evaluate evidence of declines, (2) identify real and SUlVeyS have indicated that this species has undergone nearly a possible causes for obselVed declines and geographic range statewide, regional extinction in Idaho (Figure 2) and Nevada contractions, and (3) summarize strategies for management and (Brennan 1993a). research that might be used to sustain quail populations in an ecological context. My overall purpose is to use quail populations as an example of what . happens when relationships POSSIBLE ICAUSES OF POPULATION between seemingly abundant vertebrate populations and land use DECLINES practices are taken for granted. Hopefully, these case histories will raise awareness of problems facing this unique, and often overlooked group of Characteristics of Declining Quail Populations native avifauna Populations decline when rates of birth and/or immigration are less than rates of death and/or emigration (Begon and Mortimer 1986). With respect to species such as quail, normal EVIDENCE OF DECLINES annual mortality rates can be as high as 80-90% (Rosene 1969, Leopold 1977, Roseberry and Klimstra 1984). Throughout Brennan (1993a) summarized population trends for 6 species evolutionmy time scales, quail have evolved characteristics such of quail in the United States from 1960-1989 based on Christmas as large clutch sizes (Leopold et al. 1981) and indeterminate Bird Count (CBC) data. egg-laying (Welty 1975) which selVe as reproductive strategies Three of the 6 species of quail in this study (California quail, that can potentially offset such high mortality rates. However, Callipepla squamata~ northern bobwhite~ and scaled quail, C. the high percentage of annual turnover that most quail squamata) showed statistically significant evidence of declines populations experience means that when habitat components, or (Figure 1). None of the species in this study showed evidence other key resources needed for survival are eliminated, of increasing populations (Figure 1). populations can decline and disappear at an extremely rapid rate.

5~------______~ 3.5 0.4 A. CALIFORNIA QUAIL C. MONTEZUMA QUAil r- 3 4 -0.43, P- 0.01 r.. -0.09, p .. 0.60 2.5 0.3

3 2 0.2 a: 2 1.5 ::> o 0.1 J:1 0.5 GAM BEL'S QUAIL r- 0.22, P- 0.24 ~ o~·~~~~~~~~ Q ... o~~~~~~~~~~~ a: 60 62 &4 66 68 70 72 74 76 78 80 82 84 86 88 60 62 64 6668 70 72 74 76 78 80 82 84 86 88 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 ~

a: 0.3 w E. NORTHERN BOBWHITE F. SCALED QUAil a.. D. MOUNTAIN QUAIL r- -0.6, P< 0.001 0.25 r- -0.85, P< 0.001 -I r- -0.15, P- 0.94 0.8 « 0.2 ::> 0.6 0 0.15 0.4 2 0.1

0.05 0.2

o~~~~~~~~~~ o~~~~~~~~~~~ o~~~~~~~~~~~ 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 60 82 64 66 68 70 72 74 76 78 eo 82 84 86 88 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88

YEAR Figure 1. - Quail population trends in the United States based on 31 years of Christmas Bird Count data. Statistics are correlation coefficients (r) and probability that the slope of the regreSSion line is significantly different from zero. Data from Brennan (1993a),

45 1938 1965 1989

Figure 2. - Changes in the geographic distribution of mountain quail in Idaho during the past 50 years. 1938 map based on data from Murray (1938). 1965 map based on Ormiston (1966). 1989 map compiled by Idaho Fish and Game Department and other surveys. If habitat or other limiting conditions do not become favorable challenged interpretations made about the lack of widespread, within a relatively short time period, local and regional direct antagonistic relationships between fue ants and quail extinctions can occur. Where a limiting factor is abiotic (such (Brennan 1991), they have yet to present experimental or as water from sporndic annual rninfall in the Rio Grnnde Valley circumstantial evidence that the presence of fire ants limits quail of Texas), annual bobwhite population fluctuations can be population productivity. dramatic (Lehmann 1984). In this situation, biotic habitat Issues such as fue ants, coyotes, global warming, and other components remain relatively stable, and alternating wet and city such potential epiphenomena are, in many ways, red herrings periods, which often persist across multiple years, are the that threaten to steer us off the trnck of the real problems that primaty cause of the fluctuations. However, when biotic habitat are at the root of the bobwhite decline (Brennan 1993c). These components are degrnded through changing land use, application problems relate to changing land use in agriculture and forestry, of agrochemicals, or other factors, populations of small and in the ever-increasing utbanization that eliminates bobwhite galliformes such as quail or partridge (Perdix perdix) often habitat, and/or erodes its quality on a broad scale. decline and disappear quickly and thus undergo local or regional With bobwhites, changing land uses have clearly had a broad extinctions. With quail, such extinction processes may occur so and largely negative impact on populations (Klimstra 1982, quickly and at such a broad scale that recovery in a Brennan 1991). In agriculture, the herbicides may indirectly metapopulation context (Hanski 1991, Rolstad 1991) may not reduce or eliminate arthropod resources needed by growing be possible. chicks. Elimination of native weedy plants which provide substrntes that produce abundant insects has broad, negative impacts on partridge (potts 1986). This relationship may vety Northern Bobwhite well hold true for bobwhites and other quail, but it needs to be tested. In forestty, the widespread proliferation of high-density Numerous factors have been attributed as being responsible pine plantations, and reduction in use of prescribed fire has for the broad-scale declines that northern bobwhites have eliminated hundreds of thousands of acres of old-field habitats experienced during the past 30 years. These factors range from that once produced quail (Brennan 1991). In rural social the geogrnphic expansion of the coyote (CaniS latrans) in the contexts, the collapse of the tenant farming system in the south, to broad-scale increases in hawk and owl populations, to southern U.S. and a broad-scale move from an agrarian to a the invasion of the imported fue ant (Solenopsis spp.). setVice-based economy (Winter 1988, Bradshaw and Blakeley Experimental evidence linking factors such as these to 1982) has apparently had devastating effects on quail (Brennan bobwhite declines does not exist. In some situations, 1991). circumstantial evidence of rnptor predation may be compelling The linkage between declining bobwhite populations and in the absence of changing land use and lack of agrochemicals. changing land use becomes clear when local case histories are However, linking factors such as coyotes and fire ants to the examined in light of good quail management and habitat is either broad-scale bobwhite decline are myths that must be eliminated improved or maintained. For example, case histories in through education (Brennan 1991). Study of coyote foods in the Mississippi (Brennan et al. 1991, Brennan 1992a, Brennan southeast indicated that bobwhites are the least-common dietaIy 1993c, Brennan 1993d) point to a dramatic increase in bobwhite item of coyotes (Wagner 1993). Although Allen et al. (1993) numbers when habitat conditions are improved, but other effects

46 (such as predators and fire ants) are kept constant. Conversely, likely to change. Modifying the way cattle are managed is clearly when habitat conditions are allowed to erode, bobwhite numbers the most significant opportunity for restoration of this quail in will decline concomitantly (Dimmick 1992). Furthennore, the portions of its fonner range in Idaho. vast area (200,000 hal of private lands managed for bobwhites in the Red Hills region of southern Georgia and northern Florida continues to produce abtmdant quail populations at the same time bobwhite numbers continue to decline elsewhere in the Scaled Quail southeastern coastal plain. The linkage between land use and bobwhites is an issue that has been raised on a regular basis for Evidence of the scaled quail decline swprised many of the over 60 years (Stoddard 1931, Rosene 1969, Rosebeny and participants at the Third National Quail Symposium last year. Klimstra 1984), yet, often seems to be neglected in favor of Mechanisms responsible for the decline in scaled quail some other more easily identifiable villain such as predators populations are not asl well understood as the factors behind the (Mueller 1989) or fire ants (Allen et al. 1993). northern bobwhite and mountain quail declines. There are, however, some potential relationships between excessive grazing and this decline that should be explored. Scaled quail clearly Mountain Quail have an affinity for desert grasslands with sparsely scattered shrubs (Schemnitz 1961, Brown 1989). Homogenous grasslands Mountain quail clearly represent a classic example of how without a shrub component are usually unsuitable for scaled quail populations can be sustaine

47 STRATEGIES FOR SUSTAINING QUAIL 1983). The recent uproar at the proposal to lower subsidies for IN AN ECOSYSTEM CONTEXT public land grazing fees that encourage overgrazing and associated abuses and link grazing fees on public lands with fair We need to begin with the modest assumptions that (1) quail matket values is a classic example of this recalcitrant attitude. are renewable resources, and (2) they can be sustained in the Whether these complex, wicked problems (Allen and Gould context of contemporary land use prnctices. Emerging trends in 1986) of public land management can be solved remains to be agriculture (Robinson 1990) and forest management (Sharitz et seen. al. 1992) indicate that there is some promise and hope for The fate of all quail, and many other vertebrates as well, are stopping the broad-scale declines that many quail populations clearly linked to the ways that we farm our land, graze our grass, have been experiencing. Howevet; whether the mainstream and manage our forests. Focusing on strntegies that maintain the managers in foresny and agriculture adopt these philosophical integrity and functional processes of ecosystems (Regier 1993) changes remains to be seen . would clearly be I the most effective way to sustain populations In agriculture, the direct and indirect roles of agrochemicals of wild quail. Maintaining system integrity with an ecosystem with respect to quail (especially northern bobwhite) need to be approach allows managers the opportunity to provide for the assessed. The ConselVation Headlands approach to partridge annual cycle needs of the birds. management in agricultural environments in England (potts Consider the alternatives. There have been vast amounts of 1986) appears to have profound implications for integrating resources poured into recovety efforts aimed at the endangered northern bobwhites in modem production agriculture. This masked bobwhite (Co!inus virginian us ridgwayi). Recovety approach entails reduction of Iilemicide application around field efforts were continually met with failure until a large tract of perimeters so that weedy foms and phytophagus insects can land (Buenos Aires Ranch) was purchased and managed as a grow and provide food resources for growing partridge chicks. refuge (Brown 1989). Even today, quantitative descriptions of In foresny, considerntion needs to be given to uneven-aged masked bobwhite habitat components are not available, and management strntegies that emphasize long rotation and single habitat management on Buenos Aires is largely based on the tree selection. Such foresny prnctices, when combined with "best guess" approach, because reliable information has not frequent, annual burning, have sustained abundant huntable been compiled (W. Kuvlesky, personal communication, Buenos populations of northern bobwhites in the Red Hills plantation Aires National Wildlife Refuge). counny of southern Georgia and northern Florida for over 60 The masked bobwhite, lesser prairie chicken (Tympanuchus years. Such land use prnctices can clearly selVe as a model for pallidicinctus) and other once common game birds have been habitat management in other parts of the northern bobwhite's driven to the brink of extinction by changing land use practices. range, especially on public lands where multiple uses are If contemporary trends in land use continue, and an ecosystem mandated. Another such model is the relationship between the approach to sustaining quail and other wildlife resources is endangered red-cockaded woodpecker (Picoides borealis) and ignored, then we will most likely add other species of once northern bobwhites in pine forests of the southeastern coastal common gallifonnes to this list. To the naysayers who doubt plain (Brennan and Fuller 1993). Brennan (1991) and Brennan that birds as common as quail can be potential candidates for et al. (1993) obselVed a significant, positive response of northern extinction, I offer the example of the passenger pigeon bobwhites to habitat management for the red-cockaded (Ectopistes migratorious). woodpecker at Noxubee National Wildlife Refuge in east-central Mississippi. Conversely, the private plantations that have been managed for bobwhites in the Red Hills region of Georgia and ACKNOWLEDGMENTS Florida support the largest extant population of red-cockaded woodpeckers on private lands (T. Engstrom, personal The ideas in this paper developed through the course of my communication, Tall Tunbers Research Station). In northern work on habitat and population ecology of quail that I began as California, Block et al. (1991) obselVed that mountain quail were a graduate student in 1982. R.J. Gutierrez of Humboldt State loosely affiliated with a guild of approximately 8 species of University was instrumental in providing academic opportunities birds that shared an affinity for brushy and chaparral-dominated that allowed me to develop many of these ideas. Support for vegetation Identifying similar linkages that establish positive work on mountain quail in California and Idaho was provided relationships between management for species of quail and other by the California Department of Forestry, the now-defunct terrestrial vertebrntes (or vice versa) is clearly needed. International Quail Foundation, and the still extant Chukar In contrast to some of the recent potentially positive Foundation Many of my ideas about problems facing northern conceptual developments for integrating quail with other wildlife bobwhites evolved from 1990-1993 when I was supported by resources in forest and agricultural environments, similar the Mississippi Department of Wildlife, Fisheries and Parks, and relationships in rangeland environments have apparently not worked in the Department of Wildlife and Fisheries at been established. Range managers seem to be uncooperative Mississippi State University. George Hurst deselVes exceptional when it comes to implementing comprehensive stewardship and credit for helping me see in a single afternoon how 20 years of adopting a pay-as-you-go philosophy (Ferguson and Ferguson plant succession can influence bobwhites. I thank Teresa Pruden

48 for reading an earlier draft of this paper and helping me improve woodpecker habitat management on non-target forest it, the Conference Planning Committee for providing support for vertebrates in loblolly pine forests of Mississippi: study me to attend this symposium, and Bill Block for inviting me to design and preliminary results. In D. Kulhavy, ed. present this material. Proceedings of the Third Red-cockaded Woodpecker Symposium. Stephen F. Austin State University, Nacogdoches, TX. (in press). LITERATURE CITED Brennan, L. A. and R. S. Fuller 1993, Bobwhites and red-cockaded woodpeckers: endangered species management Allen, C. R., R. S. Lutz, and S. Demarias. 1993. What about helps quail too! Quail Unlimited Magazine 12(3): 16-20. fire ants and bobwhites: a comment. Wildlife Society Bulletin Brennan, L. A. and H. A. Jacobson 1992. Northern bobwhite 21(3) (in press) (Colinus virginianus) hunter use of public wildlife areas: the Allen, G. M., and E. M. Gould, Jr. 1986. Complexity, need for proactive lmanagement. Giber Faune Sauvage 9(4). wickedness, and public forests. Journal of Forestry (in press). 84(4):20-23. . Brennan, L. A., D. Sisson, H. A. Jacobson, D. H. Amer, and Begon, M., and M. Mortimer. 1986. Population ecology: a W. Strickland. 1991. Bobwhite quail management at the unified study of animals and plants. Blackwell Scientific Circle Bar Ranch. Pages 47-49 in W. E. Cohen, ed, Synopses Publications, Oxford, U.K. 22Opp. of the 1991 bobwhite quail short course. Mississippi Block, W. M., L. A. Brennan, and R. 1. Gutierrez. 1991. Cooperative Extension SeIVice, Mississippi State University, EcomOlphological relationships of a guild of ground-foraging Mississippi State, MS birds in northern California, USA. Oecologia 87:449-458. Brown, D. E. 1989. Arizona game birds. University of Arizona Bradshaw, T. K., and E. 1. Blakeley. 1982. The changing nature Press, and Arizona Game and Fish Department. 307pp. of rural America. Pages 3-8 in W. P. Browne and D. F. Dimmick, R.W. 1992. Bobwhites on Ames Plantation, Hadwinger, eds. Rural policy problems: changing dimensions. 1966-1991: population response to a changing landscape. Lexington Books, D. C. Heath, Lexington, MA Pages 4-15 in D. C. Sisson and A. M. Bruce, eds. Proceedings Brennan, L. A. 1991. How can we reverse the northern bobwhite of the 1992 Tall Timbers Game Bird Seminar, Tall Timbers population decline? Wildlife Society Bulletin 19(2)544-555. Research Station, Tallahassee, FL. Brennan, L. A. 1992a. Return to wild quail management: the Droege, S., and 1. R. Sauer. 1990. Northern bobwhite, gray Rainey Farm success. Quail Unlimited Magazine 11(2):42-44, partridge, and ring-necked pheasant population trends 59. (1966-1988) from the North American breeding bird sUlVey. Brennan, L. A. 1992b. Regional tests of a mountain quail habitat Pages 2-30 in K. E. Church, R. E. Warner, and S. J. Brady, model. Northwestern Naturalist 72(3):100-108. eds. Perdix V: Gray partridge and ring-necked pheasant Brennan, L. A. 1993a. Strategic plan for quail management and workshop. Kansas Department of Wildlife and Parks, research in the United States: introduction and background. Emporia. In K. E. Church and T. V. Dailey, (eds). Quail III: national Ferguson, D., and N. Ferguson 1983. Sacred cows at the public quail symposium. Missouri Department of ConselVation, trough. Maverick Press, Bend, OR 25Opp. Jefferson City. (in press) Hanski, 1. 1991. Single-species metapopulation dynamics: Brennan, L. A. 1993b. Strategic plan for quail management and concepts, models and obselVations. Biological Journal of the research in the United States: problems and strategies. In K. Linnean Society 42: 17-38. E. Church and T. V. Dailey, (eds). Quail Ill: national quail Klimstra, W. D. 1982. Bobwhite quail and changing land use. symposium. Missouri Department of ConselVation, Jefferson Proceedings of the National Bobwhite Quail Symposium City. (in press) 1:65-82. Brennan, L. A. 1993c. Fire ants and northern bobwhites: a real Lehmann, V. W. 1984. Bobwhites in the Rio Grande Plain of problem or a red herring? Wildlife Society Bulletin Texas. Texas A & M University Press, College Station 371 21(3):350-354. pages. Brennan, L. A. 1993d. Strip-discing: the forgotten bobwhite Leopold, A. 1933. Game management. Charles Scribner's Sons, habitat management technique. Quail Unlimited Magazine New Yolk 481pp. 12(3):20-22. Leopold, A. S. 1977. The California quail. University of Brennan, L. A. and W. M. Block. 1986. Line transect estimates California Press, Belkeley. 281pp. of mountain quail density. Journal of Wildlife Management Leopold, A. S., R. 1. Gutierrez, and M. T. Bronson 1981. North 50(3):373-377. American game birds and mammals. Charles Scribner's Sons, Brennan, L. A., W. M. Block, and R. 1. Gutierrez. 1987. Habitat New YOtic. 198pp. use by mountain quail in northern California. Condor Mueller, B. 1989. The effects of hawks and owls on bobwhite 89(1):66-74. quail. Quail Unlimited Magazine 8(3)8-12. Brennan, L. A., 1. L. Cooper, K. E. Lucas, B. D. Leopold, and Murray, T. B. (1938) Upland game birds and their future. G. A. Hurst. 1993. Assessing the influence of red-cockaded University of Idaho Bulletin, Moscow.

49 Onniston, 1. H. 1966. The food habits, habitat and movements Sauer, J., S. Droege, and K. E. Church. 1993. Trends in North of mountain quail in Idaho. University of Idaho, Moscow. American quail populations (1966-1991) with special Potts, G. R. 1986. The partridge: pesticides, predation, and emphasis on evaluating changes in northern bobwhite conselVation. Collins, London, UK. populations. In K.E. Church and T.V. Dailey, eds. Quail Regier, H. A. 1993. The notion of natural and cultural integrity. III: national quail symposium. Missouri Department of pages 3-18 in S. Woodley, 1. Kay, and G. Francis, eds. ConselVation, Jefferson City. Ecological integrity and the management of ecosystems. St. Schemnitz, S. D. 1961. Ecology of the scaled quail in the Lucie Press, Canada Oklahoma panhandle. Wildlife Monographs 8: 1-47. Robinson, A. Y. 1990. Sustainable agriculture: a brighter Sharitz, R. R., L. R. Boring, D. H. Van Lear, and 1. E. Pinder outlook for fish and wildlife. Izaak Walton League of III. 1992. Integrating ecological concepts with natural America. Arlington, VA. resource management of southern forests. Ecological Roistad, 1. 1991. Consequences of forest fragmentation for the Applications 2(3)226-237. dynamics of bird populations: conceptual issues and the Stoddard, H.L.1 1931. The bobwhite quail: its habits, evidence. Biological Jownal of the Linnean Society preservation and increase. Charles Scribner's Sons. New 42:149-163. Your. 559pp. Roseberry, 1. L., and W. D. Klimstra. 1987. Population ecology Wagner, G. D. 1993. Coyote diet in areas of wild turkey of the bobwhite. Southern Illinois University Press, abundance during the wild turkey reproductive season. Catbondale, IL 259pp. M.S. thesis. Mississippi State University, MS 144pp. Rosene, W. 1969. The bobwhite quail: its life and management. Welty, 1. C. 1975. The life of birds. 2nd ed. W. B. Saunders, Rutgers University Press, New Brunswick, N. 1. 418 pp. Philadelphia, PA 623pp.- Sands, A. and D. Smurthwaite 1992. Upland game bird habitat Winter, W. F. 1988. Charting a course for the rural south. management on the rise. USDI Bureau of Land Management Pages 358-364 in L. 1. Bealieu, ed. The rural south in Report BLM-ID-PT-92-007-4351. National Technical crisis: challenges for the future. Westview Press, Boulder, Information Service. 37pp. CO.

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