Survival of Birds of Conservation Concern

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Factors affecting the survival of
Birds of Conservation Concern

by David Leech

4. Factors affecting population size

The size of a population is dependent on the balance between production of new individuals through reproduction and loss of individuals through mortality. Populations will increase in size if the number of recruited individuals exceeds the number lost from the population, and will decrease in size if the opposite is true. The breeding performance and survival rates of individuals in a population therefore both have the potential to influence population size.

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