Laboratory of Fish and Amphibian Ethology, Behavioural Biology Unit, Department of Biology, Ecology and Evolution, University of Liège, Liège, Belgium.
PLoS One. 2013 May 3;8(5):e62727. doi: 10.1371/journal.pone.0062727. Print 2013.
Although rare species are often the focus of conservation measures, more common species may experience similar decline and suffer from the same threatening processes. We tested this hypothesis by examining, through an information-theoretic approach, the importance of ecological processes at multiple scales in the great crested newt Triturus cristatus, regionally endangered and protected in Europe, and the more common smooth newt, Lissotriton vulgaris. Both species were similarly affected by the same processes, i.e. suitability of aquatic and terrestrial components of their habitat at different scales, connectivity among breeding sites, and the presence of introduced fish. T. cristatus depended more on water depth and aquatic vegetation than L. vulgaris. The results show that environmental pressures threaten both common and rare species, and therefore the more widespread species should not be neglected in conservation programs. Because environmental trends are leading to a deterioration of aquatic and terrestrial habitat features required by newt populations, populations of the common species may follow the fate of the rarest species. This could have substantial conservation implications because of the numerical importance of common species in ecosystems and because commonness could be a transient state moving towards rarity. On the other hand, in agreement with the umbrella species concept, targeting conservation efforts on the most demanding species would also protect part of the populations of the most common species.
虽然稀有物种通常是保护措施的重点，但更常见的物种可能也会经历类似的减少，并受到同样的威胁过程的影响。我们通过信息论方法检验了这一假设，研究了在欧洲区域性濒危保护的大蝾螈（Triturus cristatus）和更为常见的滑螈（Lissotriton vulgaris）中，多个尺度的生态过程的重要性。这两个物种都受到相同过程的影响，例如其栖息地的水生和陆地部分在不同尺度上的适宜性、繁殖地之间的连通性以及引入鱼类的存在。大蝾螈比滑螈更依赖水深和水生植被。结果表明，环境压力威胁着常见和稀有物种，因此，在保护计划中不应忽视更广泛分布的物种。由于环境趋势导致蝾螈种群所需的水生和陆地栖息地特征恶化，常见物种的种群可能会跟随最稀有种群的命运。这可能会产生重大的保护影响，因为常见物种在生态系统中具有数量上的重要性，而且常见状态可能是一种向稀有状态转变的暂时状态。另一方面，与伞物种概念一致，将保护工作集中在最具需求的物种上，也可以保护最常见物种的部分种群。
