Similar Local and Landscape Processes Affect Both a Common and a Rare Newt Species

Abstract

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.

Cross‐scale effects of structural and functional connectivity in pond networks on amphibian distribution in agricultural landscapes

“…However, in other studies, L. vulgaris occurrence has proven to be rather favoured by open landscapes, especially grasslands, and even positively responded to the distance to the nearest woodland (Denoël & Ficetola, ). This could explain the positive link we find for network resistance, although there are still contradicting results about the effect of the distance to the nearest forest on this species (Table in Denoël et al., ). If woodlands constitute actual barriers for L. vulgaris , our evaluation according to which the tree‐filled areas were favourable habitats might be reconsidered (Garshelis, ).…”

Beavers (Castor fiber) increase habitat availability, heterogeneity and connectivity for common frogs (Rana temporaria)

“…Beavers can increase common frog abundance manifold, so that even in years of low breed ing rates, abundances in beaver ponds alone can reach a level typical of common frog popu lations in woodlands without beavers. Beavers thereby enhance landscape connectivity for am phibians and can contribute significantly to the stabilisation of populations of common species (Dalbeck and Weinberg, 2009) whose impor tance in functional ecosystem relationships de pend on their abundance (Denoel et al, 2013), e.g. common frogs and common newt species (e.g.…”

What remains from a 454 run: estimation of success rates of microsatellite loci development in selected newt species (Calotriton asper, Lissotriton helveticus, and Triturus cristatus) and comparison with Illumina‐based approaches

“…; Denoël ; Denoël et al. ). Thus far, only eight applicable microsatellite loci for T. cristatus have been published (Krupa et al.…”