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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.
C. Wilson: deceased 相似文献
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The role of adjacent habitats in rodent damage levels in Australian macadamia orchard systems 总被引:1,自引:0,他引:1
Estimates of damage caused by Rattus rattus to macadamia nut crops were determined from several Australian macadamia orchards during the 1995/1996 growing season. Both the extent and pattern of crop damage were associated with the type of adjacent non-crop habitat. Orchards adjacent to large, temporally stable, structurally complex habitats experienced high levels of rodent damage (mean 9.9%). Front row trees adjacent to these stable habitats showed significantly higher damage than trees further into the orchard, suggesting an interaction between the crop and non-crop habitats. Orchards adjacent to highly modified grasslands and other orchard blocks exhibited the lowest levels of damage (mean 0.8%), with the damage in these areas being uniformly distributed.
Rattus rattus was the main rodent species responsible for damage. Animals were not distributed uniformly throughout the orchard system. High densities of rodents were found in temporally stable adjacent habitats, while low densities were present in temporally unstable adjacent habitats and cropped areas. The stability and complexity of adjacent non-crop habitats directly affected the potential for rodent damage to macadamia crops. Manipulation of large, temporally stable adjacent habitats therefore could be an effective method for reducing rodent damage in macadamia orchards. 相似文献
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