The importance of demographic uncertainty: An example from the helmeted honeyeater Lichenostomus melanops cassidix

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Abstract

Models that account for aspects of the behaviour and ecology of helmeted honeyeaters Lichenostomus melanops cassidix are developed. These highlight the importance of demographic uncertainty in population viability analysis. Differences between and relationships among individuals are important components of population dynamics. Adding individual detail to demographic models can change estimates of extinction risk. Demographic uncertainty can cause greater variation in population size than indicated by standard modelling procedures. Accurate prediction of this level of variation is limited by ignorance of population dynamics. Implications for metapopulation dynamics and reserve design are discussed. The helmeted honeyeater population faces an appreciable risk of decline from demographic uncertainty alone.

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