Habitat Evaluation: Do Use/Availability Data Reflect Carrying Capacity?

Abstract

Evaluating the quality of habitat for wildlife is fundamentally important to decisions on land use. Habitat evaluation models are frequently based on the assumption that habitat use/availability data correspond in some fashion to the carrying capacities of habitats for populations and that the correspondence is independent of realized population density. We believe that assumption may be misleading whenever the quality of habitat resources is not directly related to their quantity. We use a simple model to illustrate that habitat use/availability ratios change as population density changes and may have no relation to carrying capacity when resource quality and quantity are not substitutable for one another. We advocate developing habitat evaluation systems that are based on a mechanistic understanding of relations between resource acquisition by individuals and the dynamics of populations.