A common rule for the scaling of carnivore density

Carbone and Gittleman derived a simple, general rule linking carnivore population density to the productivity of the prey base, showing across species that roughly the same amount of prey biomass supports a given mass of predator. Using data spanning small to large carnivores, they demonstrated that about 10,000 kg of prey supports around 90 kg of a given carnivore, with body-size and energetic scaling explaining much of the variation. The rule provides a quantitative expectation for how many lions, tigers, pumas or smaller cats a landscape can hold given its prey, complementing prey-preference and carrying-capacity models. It is a foundational macroecological reference for predator density and conservation target-setting.