Survival and delayed breeding in male blue grouse

We present an analysis of survival of male blue grouse (Dendragapus obscurus) using known-aged individuals and examine the results in terms of the evolution of delayed breeding. Males had low rates of mortality and, among 2-year-olds, mortality rates of territorial and nonterritorial birds were the same. Up to 6 years of age, males had life expectancies of at least 2 years. Males that postponed breeding and survived had a 40–45% chance of eventually obtaining a high-quality site for a territory. If males had not delayed breeding they likely would have had to settle on areas where opportunities for breeding appear to be low. Thus, survival patterns of males are consistent with the hypothesis that it is advantageous for some males to delay breeding if high-quality sites cannot be obtained.