Interspecific Competition and Extinction-Prone Species

群落生态学中一个反复出现的主题是种间竞争极大地影响了群落中脊椎动物物种的分布和丰度，这种竞争可能导致种群灭绝。人们对陆生蝾螈进行了广泛的研究，以检验有关竞争的理论，许多物种之间的种间竞争似乎很激烈。在北美东部，广泛分布和丰富的物种似乎是强有力的竞争对手。较弱的竞争者似乎分布有限，许多这类物种被列为受威胁或濒危物种。本研究将探讨七种陆地蝾螈对之间竞争相互作用（特别是种间领土）的可能性。在自然栖息地进行的实验将检验关于种内和种间空间竞争的假设，而竞争性释放实验将检验关于竞争强度的假设。实验室实验将测试在侵略性遭遇、信息素交流和获取食物资源过程中关于种内和种间战斗策略的假设。在美国东部，一个广泛分布的物种与三个地理上孤立的物种交界。这三个孤立的物种被认为是灭绝的倾向，因为从广泛分布的物种对领土的激烈的种间竞争。这项研究将提供有价值的实地和实验室实验，为经常观察到的导致两栖动物种群数量下降的因素提供重要证据，尤其是蝾螈。

A recurrent theme in community ecology is that interspecific competition greatly influences the distributions and abundances of vertebrate species in communities, and that such competition can lead to extinctions of populations. Terrestrial salamanders have been extensively studies to test theories about competition, and interspecific competition appears to be intense among many species. In eastern North America, widely distributed and abundant species appear to be strong competitors. Weaker competitors appear to have limited distributions and many such species are listed as threatened or endangered. This research will examine the possibility of competitive interactions (particularly interspecific territoriality) between seven species pairs of terrestrial salamanders. Experiments in natural habitats will test hypotheses about intra- and interspecific competition for space, and competitive release experiments will test hypotheses concerning the intensity of competition. Laboratory experiments will test hypotheses about intra- and interspecific combat tactics during aggressive encounters, pheromonal communication, and capturing of food resources. %%% In the eastern US, one widely distributed species interfaces with three geographically isolated species. The three isolated species are considered to be extinction prone as a consequence of severe interspecific competition for territories from the widely distributed species. This research will provide valuable field and laboratory experiments that will provide vital evidence regarding factors leading to the frequently observed population decline of amphibians, in general, and several species a salamanders, in particular.