title: A common rule for the scaling of carnivore density.
abstract: Population density in plants and animals is thought to scale with size as a result of mass-related energy requirements. Variation in resources, however, naturally limits population density and may alter expected scaling patterns. We develop and test a general model for variation within and between species in population density across the order Carnivora. We find that 10,000 kilograms of prey supports about 90 kilograms of a given species of carnivore, irrespective of body mass, and that the ratio of carnivore number to prey biomass scales to the reciprocal of carnivore mass. Using mass-specific equations of prey productivity, we show that carnivore number per unit prey productivity scales to carnivore mass near -0.75, and that the scaling rule can predict population density across more than three orders of magnitude. The relationship provides a basis for identifying declining carnivore species that require conservation measures.
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK. chris.carbone@ioz.ac.uk
authors.forename: Chris
authors.initials: C
authors.lastname: Carbone
authors.forename: John L
authors.initials: JL
authors.lastname: Gittleman
mesh_terms: D000818:Animals; D018533:Biomass; D001835:Body Weight; D002335:Carnivora / Q000502:physiology*; D003247:Conservation of Natural Resources; D017753:Ecosystem; D020387:Food Chain; D008954:Models, Biological; D011156:Population Density; D013045:Species Specificity