Environmental Conservation

Papers

Using connectivity metrics and niche modelling to explore the occurrence of the northern crested newt Triturus cristatus (Amphibia, Caudata) in a traditionally managed landscape

TIBOR HARTELa1a2a3 c1, SZILÁRD NEMESa1, KINGA ÖLLERERa4, DAN COGĂLNICEANUa5, COSMIN MOGAa1 and JAN W. ARNTZENa3

a1 Mihai Eminescu Trust, Cojocarilor 10, 545400 Sighisoara, Romania

a2 Babeş-Bolyai University, Department of Taxonomy and Ecology, Clinicilor 5–7, 400006 Cluj-Napoca, Romania

a3 Research Department Terrestrial Zoology, Netherlands Centre for Biodiversity Naturalis, PO Box 9517, 2300 RA Leiden, The Netherlands

a4 Institute of Biology, Romanian Academy, Splaiul Independenţei 296, 060031 Bucharest, Romania

a5 Ovidius University Constanta, Faculty of Natural Sciences, Blv. Mamaia 124, Romania

SUMMARY

Spatial models are increasingly employed to help understand the distribution of organisms and establish conservation priorities. Classic patch-orientated models may have limited power to accurately predict the organisms' distributions. Pond breeding amphibians are appropriate study organisms because of their complex life cycle, low dispersal and sensitivity to environmental conditions. Here connectivity metrics and niche modelling were used to predict the occurrence of the northern crested newt in a rural landscape from central Romania. Pond-related variables, such as macrophyte cover and the presence of predatory fish, were the most important predictors of newt occurrence, followed by one landscape-related variable (urbanization) and a connectivity metric (nearest neighbouring occupied pond). Most of the landscape and connectivity variables were not adequate predictors, presumably because most of the terrestrial habitats in this traditionally used rural landscape are ecologically optimal for amphibians. Conservation measures for the northern crested newt should promote the preservation of traditional extensive agricultural practices and discourage stocking of ponds with predatory fish.

(Received December 15 2009)

(Accepted April 14 2010)

(Online publication July 27 2010)

Correspondence

c1 Correspondence: Dr Tibor Hartel Tel/Fax: +40 265 77600 e-mail: asobeka@gmail.com