Bird coloration: Unprofitable prey model supported by ringing data

Most ornithologists accept the classical view that conspicuous coloration of male birds has evolved by sexual selection, either through female choice or through inter-male competition. In either case, advantage due to bright coloration is thought to be balanced by an increased predation rate that seems an inevitable corollary of greater conspicuousness. More recently, Baker & Parker (1979) have argued that variation in conspicuousness between birds is more consistent with an "unprofitable prey" model, bright coloration advertising to potential predators that the bird is difficult to catch. Unprofitable prey and classical sexual selection models, therefore, predict opposite relations between predation rate and conspicuousness. On the unprofitable prey model the greatest predation rates are experienced by cryptic birds; on sexual selection models, by conspicuous birds. The authors test these predictions using ringing and recovery data for 14 species of British passerines.