Conservation Genetics

, Volume 11, Issue 4, pp 1435–1443 | Cite as

Molecular assessment of population differentiation and individual assignment potential of Nile crocodile (Crocodylus niloticus) populations

  • Evon R. Hekkala
  • George Amato
  • Rob DeSalle
  • Michael J. Blum
Research Article

Abstract

Conservation and management of widespread species can be improved if populations exhibiting genetic differentiation are recognized as local management units. Specimens of Nile crocodile (Crocodylus niloticus) corresponding to major river drainage systems from Eastern Africa and Madagascar, and a small set of samples from Western Africa, were analyzed using multilocus genotyping to evaluate the potential to discriminate among locations and to assign individuals to population of origin. Populations from all sampled regions exhibited marked levels of genetic and genotypic differentiation as assessed by significant FST values and Bayesian analysis of population structure. At the regional level, the majority (94%) of all specimens were successfully assigned to the population of origin using only four microsatellite loci. Three populations sampled within Madagascar required the use of 12 loci for successful assignment of greater than 84%. Our findings demonstrate a need for alternative management strategies that consider the biogeographic sub-structuring of Nile crocodiles associated with major river drainages in Africa and Madagascar.

Keywords

Nile crocodile Crocodylus niloticus Genetic variation Population divergence Management units African biogeography 

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Evon R. Hekkala
    • 1
    • 3
  • George Amato
    • 1
  • Rob DeSalle
    • 2
  • Michael J. Blum
    • 3
  1. 1.Sackler Institute for Conservation GeneticsAmerican Museum of Natural HistoryNew YorkUSA
  2. 2.Invertebrate ZoologyAmerican Museum of Natural HistoryNew YorkUSA
  3. 3.Department of BiologyTulane UniversityNew OrleansUSA

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