Gaudenti Nicole, Nix Emmeleia, Maier Paul, Westphal Michael F, Taylor Emily N
Biological Sciences Department California Polytechnic State University San Luis Obispo California USA.
Central Coast Field Office US Bureau of Land Management Marina California USA.
Ecol Evol. 2021 Oct 12;11(21):14843-14856. doi: 10.1002/ece3.8170. eCollection 2021 Nov.
Global climate change is already contributing to the extirpation of numerous species worldwide, and sensitive species will continue to face challenges associated with rising temperatures throughout this century and beyond. It is especially important to evaluate the thermal ecology of endangered ectotherm species now so that mitigation measures can be taken as early as possible. A recent study of the thermal ecology of the federally endangered Blunt-nosed Leopard Lizard () suggested that they face major activity restrictions due to thermal constraints in their desert habitat, but that large shade-providing shrubs act as thermal buffers to allow them to maintain surface activity without overheating. We replicated this study and also included a population of with no access to large shrubs to facilitate comparison of the thermal ecology of populations in shrubless and shrubbed sites. We found that without access to shrubs spent more time sheltering inside rodent burrows than lizards with access to shrubs, especially during the hot summer months. Lizards from a shrubbed site had higher midday body temperatures and therefore poorer thermoregulatory accuracy than from a shrubless site, suggesting that greater surface activity may represent a thermoregulatory trade-off for . Lizards at both sites are currently constrained from using open, sunny microhabitats for much of the day during their short active seasons, and our projections suggest that climate change will exacerbate these restrictions and force to use rodent burrows for shelter even more than they do now, especially at sites without access to shrubs. The continued management of shrubs and of burrowing rodents at sites is therefore essential to the survival of this endangered species.
全球气候变化已经导致世界范围内众多物种灭绝，在本世纪及以后，敏感物种将继续面临与气温上升相关的挑战。现在评估濒危变温动物物种的热生态学尤为重要，以便尽早采取缓解措施。最近一项关于联邦濒危钝鼻豹蜥（）热生态学的研究表明，由于其沙漠栖息地的热限制，它们面临着主要的活动限制，但大型遮荫灌木起到了热缓冲作用，使它们能够在不过热的情况下维持地面活动。我们重复了这项研究，还纳入了一个无法接触大型灌木的种群，以便比较无灌木和有灌木地点的种群热生态学。我们发现，无法接触灌木的蜥蜴比能接触灌木的蜥蜴在啮齿动物洞穴内躲避的时间更长，尤其是在炎热的夏季。来自有灌木地点的蜥蜴中午体温更高，因此与来自无灌木地点的蜥蜴相比，体温调节精度更低，这表明更多的地面活动可能代表了钝鼻豹蜥在体温调节方面的权衡。在它们短暂的活跃季节里，两个地点的蜥蜴目前在一天中的大部分时间都被限制使用开阔、阳光充足的微生境，我们的预测表明，气候变化将加剧这些限制，并迫使钝鼻豹蜥比现在更多地利用啮齿动物洞穴躲避，尤其是在无法接触灌木的地点。因此，持续管理钝鼻豹蜥栖息地的灌木和穴居啮齿动物对于这种濒危物种的生存至关重要。
