Study design and interpretation of mammalian carnivore density estimates

摘要: Ecological theory and wildlife management often depend on reliable comparison interpretation of population density estimates. A synthesis 1,772 mammalian carnivore estimates (713 unique to reference, species, site, size study area) from 74 species revealed global patterns among aspects interpretive design that undermine the reliability usefulness comparisons. The spatial extent area could explain most variation in density, probably because areas are typically delineated around clusters. We related scale-defined (regression residuals) 28 other variables measured published literature, but none provided convincing biological explanation density. Many were possibly ill-suited identifying factor(s) influencing Study attributes findings reported inconsistently, subject ideological motivations. Descriptions vegetation difficult relate More intensive sampling estimation methods produced above-average estimates, differences slight evidence lacking for concluding whether these more also accurate. first underlying factor extracted principle-components analysis described growing recognition declines range reductions large-bodied carnivores, which has influenced design. Another an increasing trend be compared extrapolated larger areas, without adjusting effect scale. To understand factors distribution abundance, reporting (e.g., site description with maps) will need represent available pool locations, ecological conditions at larger-than-conventional temporal scales.