Conservation Genetics

, Volume 16, Issue 4, pp 823–832 | Cite as

Genetics of a head-start program to guide conservation of an endangered Galápagos tortoise (Chelonoidis ephippium)

  • Evelyn L. Jensen
  • Washington Tapia
  • Adalgisa Caccone
  • Michael A. Russello
Research Article


Critically endangered wildlife species typically require intensive management using a variety of in situ and ex situ approaches. Yet, despite broad application of ex situ conservation strategies, comparatively few programs incorporate genetic tools into management decisions and monitoring efforts. This is the case with the giant Galápagos tortoise endemic to Pinzón Island (Chelonoidis ephippium); a head-start program has been in place for 50 years without an evaluation of whether this conservation intervention has captured the breadth of diversity present in the wild population. Here we used microsatellite genotypic data to reconstruct patterns of within- and among-population genetic variation in the wild and captivity, and to assess the degree to which head-start cohorts and adult captive founders are representative of the gene pool in situ. We found that Pinzón giant tortoises maintain high levels of variation in situ despite their well-documented decline and that the founders of the captive population are a reasonably diverse and representative group. However, we also found that the head-start cohorts are not representative of the wild population, as evidenced by significant genetic differentiation between the in situ and ex situ samples and by the private alleles detected in both. Future head-start activities should broaden the source locations of eggs and hatchlings to more comprehensively capture the extent and distribution of genetic variation in this critically endangered keystone herbivore. More broadly, this study further highlights the utility of integrating genetic information within ex situ conservation programs.


Captive breeding Ex situ conservation Giant Galápagos tortoise Pinzón Island Microsatellite 



We gratefully acknowledge the Parque Nacional de Galápagos for support, logistics and assistance with sampling, particularly Fausto Llerena and Galo Quezada. Claudia Hollatz also assisted with sample collection and Linda Cayot provided valuable feedback on an earlier version of this manuscript. This work was funded by the Mohamed bin Zayed Species Conservation Fund (project # 62R63567; MR, GC, WT). EJ was supported by a National Science and Engineering Research Council Postgraduate Scholarship. GC was supported by the Yale Institute for Biospheric Studies.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Evelyn L. Jensen
    • 1
  • Washington Tapia
    • 2
  • Adalgisa Caccone
    • 3
  • Michael A. Russello
    • 1
  1. 1.Department of BiologyUniversity of British ColumbiaKelownaCanada
  2. 2.Giant Tortoise Restoration InitiativeGalápagos ConservancyPuerto AyoraEcuador
  3. 3.Department of Ecology & Evolutionary BiologyYale UniversityNew HavenUSA

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