|HOME SCHEDULE AUTHOR INDEX SUBJECT INDEX|
Separating effects of patch size and shape from corridor effects on butterfly movement.
Haddad, Nick*,1, Tewksbury, Josh2, 1 Department of Zoology, Raleigh, NC2 Department of Zoology, Gainesville, FL
ABSTRACT- Recent studies have found that, for many species, corridors increase animal movement rates and populations sizes. However, connectivity is inevitably confounded with other changes to patch characteristics, like their size and shape. Thus, it is often difficult to determine whether connectivity, or other patch attributes, were the causal factors that increased movement rates or population sizes. This distinction is important in conservation, as one critical debate surrounding corridors is whether to connect patches, or to create bigger patches. We conducted a large-scale, replicated experiment, where some patches were connected by corridors and others were not. Unconnected patches varied in shape, and were equal in area to a patch plus a corridor, thus simulating an alternative strategy for habitat conservation. We found that, after controlling for patch size and shape, corridors still significantly increased movement rates of two butterfly species. Our results show that corridors have potential conservation benefits that extend beyond those obtained by increasing patch area alone.
KEY WORDS: corridor, movement, conservation, dispersal