CRB: The Impact of Forest Fire Management on the Population Structure of Crotaphytus collaris

小行星9610219 在保育濒危物种和生境方面，园境管理是否比只专注于物种或生境本身的策略更有成效和效率？ 很少有研究真正记录景观管理对濒危或受威胁物种的影响。 华盛顿大学的艾伦·邓普顿博士提议研究景观层面的火灾管理对国家濒危物种--东部领蜥蜴（Crotaphytus collaris）的影响。 这种东领蜥蜴生活在欧扎克的林间空地上，这些空地是裸露的岩石，代表着沙漠或干燥的草原般的微栖息地。 奥扎克森林大火的扑灭使得树木侵入并遮蔽了林间空地，导致了有领蜥蜴和其他林间空地特有物种的灭绝。 邓普顿博士和其他人过去的研究表明，当项圈蜥蜴被转移到通过清理和燃烧恢复的空地上时，它们可以茁壮成长，但是即使附近有来源种群，恢复的空地也不会自发地被蜥蜴殖民。 领蜥蜴最初是怎么来到贫民区的？ 答案可能在于最近欧扎克发生的一个剧烈变化--积极灭火。 从历史上看，火灾不仅维持了林间空地的栖息地，也维持了开阔的林地栖息地。 随着最近对火灾的镇压，森林现在有了厚厚的林下植被，这可能会抑制有领蜥蜴的扩散。 通过焚烧整个景观（森林和沼泽地），有可能恢复沼泽地的栖息地和沼泽地物种的扩散能力。 位于奥扎克的派克牧场一直是过去林地恢复工作的所在地。 从1984年开始，蜥蜴种群被转移到那里，取得了巨大的成功。 尽管如此，迁移的种群之间仍然没有扩散，也没有在未被占用但恢复的沼泽地（有些接近64米）殖民。在与密苏里州保护部的合作下，1994年在派克牧场开始了一些初步的景观燃烧。继1994年的一次燃烧和1996年的第二次燃烧之后，林间空地种群的扩散和新林间空地的殖民化都出现了非常显着的增加。 邓普顿博士建议继续跟踪烧伤地区蜥蜴种群的命运，既进行遗传调查，也进行传统的标记/重新捕获研究。遗传和标记/重新捕获数据将允许严格测试在几个不同的生境和地理尺度上的扩散，基因流动和殖民化的动态。 这些研究最终将允许详细检查和严格测试三个相互关联的问题基本上的保护生物学：局部灭绝和退化，栖息地破碎化，并扩大到恢复地区的范围。

9610219 Templeton Is landscape management a more effective and efficient approach to the conservation of endangered species and habitats than strategies which focus solely on the species or habitats themselves? Few studies have actually documented the impact of landscape management upon endangered or threatened species. Dr. Alan Templeton, of Washington University, proposes to study the impact of fire management at the landscape level on the state-threatened species, the eastern collared lizard (Crotaphytus collaris). The eastern collared lizard is found on Ozark glades-barren rocky outcrops that represent a desert or dry prairie-like microhabitat. The suppression of forest fires in the Ozarks has allowed trees to invade and shade over the glades, resulting in the local extinction of collared lizards and other species unique to the glade habitats. Past work by Dr. Templeton and others has shown that collared lizards could thrive when translocated into glades restored by clearing and burning, but a restored glade was never colonized spontaneously by the lizards even when nearby source populations were available. How did collared lizards get to glades in the first place? The answer may lie in one recent and drastic change in the Ozarks-active suppression of fire. Historically, fires not only maintained the glade habitat, but also maintained an open woodland habitat. With the recent suppression of fires, the forest now has a thick understory that may inhibit dispersal of collared lizards. By burning the entire landscape (forests and glades), it may be possible to restore both glade habitats and the ability of glade species to disperse. The Peck Ranch, in the Ozarks, has been the site of past glade restoration work. Starting in 1984, lizard populations were translocated there with great success. Nevertheless, there was still no dispersal among the translocated populations and no colonization of unoccupied but restored glades (some as close as 64 meters). In collaboration with the Missouri Department of Conservation, some preliminary landscape burns were initiated in 1994 on the Peck Ranch. Following a burn in 1994 and a second burn in 1996 highly significant increases have occurred in both dispersal among glade populations and colonization of new glades. Dr. Templeton proposes to continue following the fate of the lizard populations in the burn areas with both genetic surveys as well as traditional mark/recapture studies. The genetic and mark/recapture data will allow rigorous tests about the dynamics of dispersal, gene flow and colonization at several different habitat and geographical scales. These studies ultimately will allow a detailed examination and rigorous testing of three interrelated issues fundamental to much of conservation biology: local extinction and recolonization, habitat fragmentation, and range expansion into restored areas.