Corridors and connectivity: when use and function do not equate Research Article Received: 22 March 2005 Accepted: 05 November 2005 DOI:
Cite this article as: Horskins, K., Mather, P.B. & Wilson, J.C. Landscape Ecol (2006) 21: 641. doi:10.1007/s10980-005-5203-6 Abstract
Connectivity, or the integration of populations into a single demographic unit, is an often desired, but largely untested aspect of wildlife corridors. Using a corridor system that was established at least 85 years prior, we investigated the extent of connectivity provided. This was undertaken using a combined ecological and genetic approach with connectivity estimated by gene flow. Vegetation within the corridor was found to be comparable in physical structure and species composition to that within the connected patches and the two target species (
Melomys cervinipes and Uromys caudimaculatus) were shown to occur along the corridor but not within the surrounding matrix. These factors indicated that the corridor was suitable for use as a model system. The population structure (weights of individuals, sex ratios and the percentage of juveniles) of both species were also similar within the corridor and the connected patches suggesting that the corridor provided the resources necessary to sustain breeding populations along its length. Despite this, populations in patches linked by the corridor were found to show the same significant levels of genetic differentiation as those in isolated habitats. M. cervinipes, but not U. caudimaculatus, also showed population differentiation within the continuous habitat. Although based on only one corridor system, these results clearly demonstrate that connectivity between connected populations will not always be achieved by the construction or retention of a corridor and that connectivity cannot be inferred solely from the presence of individuals, or breeding populations, within the corridor. Keywords Connectivity Gene flow Habitat use Matrix Melomys cervinipes Populations Rainforest Uromys caudimaculatus Wildlife corridor References Aars, J., Ims, R.A., Liu, H-P., Mulvey, M., Smith, M.H. 1998 Bank voles in linear habitats show restricted gene flow as revealed by mitochondrial DNA (mtDNA) Mol. Ecol. 7 1383 1389 PubMed CrossRef Google Scholar Amos, W., Harwood, J. 1988 Factors affecting levels of genetic diversity in natural populations Philos. Trans. Roy. Soc. Lond. B 353 177 186 CrossRef Google Scholar
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