Genetic conservation in captive populations and endangered species

  • Philip W. Hedrick
Part of the Monographiae Biologicae book series (MOBI, volume 67)


Many rare and endangered species require genetic conservation strategies involving an ex situ management phase prior to their reintroduction in nature. Since small populations are likely to lose genetic variation and suffer from inbreeding depression, these strategies are designed in genetic terms to monitor and avoid these effects as short-term goals, and to retain reestablishment or adaptive potential in nature as the long-term goal. Population genetic theory helps us define the concepts of effective population size, inbreeding and population subdivision, and discuss changes in homozygosis, genetic variance, and fitness in small populations. Estimates of several parameters in these models are presented for three examples (Cheetah, Przewalski’s horse, Speke’s gazelle). Intermatings among different populations bred in captivity or conserved in natural habitats can be guided (but not exactly prescribed) by the genetic models of migration, mating systems, and drift. Rates of changes in the level of inbreeding can be monitored to avoid drastic fitness losses, and thereby evolving tolerance of certain amount of inbreeding. These ex situ methods are designed to supplement and never to substitute for in situ conservation.


Effective Population Size Endangered Species Inbreeding Depression Captive Population Juvenile Mortality 
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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Philip W. Hedrick
    • 1
  1. 1.Department of BiologyPennsylvania State UniversityUSA

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