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

9610219邓普顿的景观管理是否比只注重物种或栖息地本身的战略更有效和更有效地保护濒危物种和栖息地？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Alan Templeton博士建议研究景观层面的火灾管理对国家濒危物种--东部衣领蜥蜴(Croaphytus Collaris)的影响。东部衣领蜥蜴是在奥扎克沼泽上发现的--奥扎克沼泽是一种贫瘠的露出地面的岩石，代表着沙漠或干燥的草原般的微生境。对奥扎克森林大火的扑灭使树木入侵并遮蔽了空地，导致领蜥蜴和空地栖息地特有的其他物种在当地灭绝。邓普顿博士和其他人过去的研究表明，当被转移到通过砍伐和焚烧恢复的空地时，领蜥蜴可以茁壮成长，但恢复后的空地从来不会自发地被蜥蜴殖民，即使附近有来源种群。一开始，衣领蜥蜴是如何来到林间空地的？答案可能在于欧扎克最近的一个重大变化--主动灭火。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。随着最近对火灾的扑灭，这片森林现在有了厚厚的林下植被，这可能会阻碍衣领蜥蜴的扩散。通过焚烧整个景观(森林和空地)，有可能恢复空地栖息地和空地物种的分散能力。Ozarks的Peck牧场过去一直在进行林间空地的修复工作。从1984年开始，蜥蜴种群被转移到那里，取得了巨大的成功。然而，在迁移的人口中仍然没有分散，也没有殖民空地但恢复了空地(有些甚至接近米)。1994年，与密苏里州自然保护部合作，在佩克牧场开始了一些初步的景观焚烧。在1994年的一次焚烧和1996年的第二次焚烧之后，在林地种群中的扩散和新林地的殖民都出现了极大的增加。邓普顿博士建议继续通过基因调查和传统的标记/重新捕获研究来跟踪烧伤地区蜥蜴种群的命运。遗传和标记/重新捕获数据将允许对几个不同栖息地和地理尺度上的扩散、基因流动和殖民动态进行严格的测试。这些研究最终将允许对许多保护生物学基本的三个相互关联的问题进行详细的检查和严格的测试：局部灭绝和重新殖民、栖息地碎片化以及范围扩大到恢复的地区。

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.