| Popis: |
Amphibians are declining globally, and efforts are underway to establish long-term programs to monitor population trends. Because researchers are constrained to sampling a small subset of populations that occur across a landscape, monitoring units should be selected that maximize the statistical independence of population responses to environmental stressors. Breeding sites of pond-breeding amphibians are often clustered locally, and habitat switching between neighboring ponds could significantly compromise both demographic and statistical independence. This raises a fundamental issue of whether the basic monitoring unit for trend analysis should be an individual pond or a cluster of local ponds. To help resolve the degree of demographic independence within a cluster of local ponds, we conducted a spatial-scale analysis of breeding-population synchrony of the wood frog (Rana sylvatica) and spotted salamander (Ambystoma maculatum) in four national parks in Kentucky, North Carolina, and Tennessee, USA. We u... |
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