Interannual variation in bird-landscape relations: understanding sources of a pervasive conservation dilemma

摘要

Interannual variation in bird-landscape relations is pervasive, and it generates decision dilemmas for conservationists who use such relations to support landscape-level planning, acquisition and management. Interannual variation occurs in two ways. Model consistency refers to agreement among years in the variables and directions of relations in a model for a species. R-2 consistency measures variation in the strengths of association between bird and landscape variables for a species among years. We examined how distributional and biological traits of species, model-selection certainty (likelihood the best model was selected in a given year), and model complexity (number of landscape variables) were associated with interannual variation in bird-landscape relations for 72 species in the Appalachian Mountains, USA. Abundant, narrowly distributed species, and cavity nesters exhibited higher model consistency, but model-selection certainty, not species' traits or model complexity, had the most influence on model and R-2 consistency. Increasing model-selection certainty by improving sampling methods and model-selection strategies may be the most effective way to cope with interannual variation in bird-landscape relations.