Conservation Genetics

, Volume 13, Issue 5, pp 1317–1328

Genetic analysis suggests high conservation value of peripheral populations of Chihuahau chub (Gila nigrescens)

Authors

    • Department of Biology and Museum of Southwestern BiologyUniversity of New Mexico
  • Alana Sharp
    • Department of Biology and Museum of Southwestern BiologyUniversity of New Mexico
  • Jerry Monzingo
    • USDA Forest Service
  • David L. Propst
    • Department of Biology and Museum of Southwestern BiologyUniversity of New Mexico
  • Thomas F. Turner
    • Department of Biology and Museum of Southwestern BiologyUniversity of New Mexico
Research Article

DOI: 10.1007/s10592-012-0374-6

Cite this article as:
Osborne, M., Sharp, A., Monzingo, J. et al. Conserv Genet (2012) 13: 1317. doi:10.1007/s10592-012-0374-6

Abstract

Genetic drift is expected to be the predominant evolutionary force in small, fragmented peripheral populations, which can lead to divergent allele frequencies and lowered diversity compared to the core population. Peripheral populations are not considered a high priority for conservation for this reason. However, peripheral populations may possess unique genetic variability not found elsewhere in the species’ range, and may be especially important if core populations are at extirpation risk. Here, we characterized levels and patterns of genetic diversity at microsatellites and mtDNA for the peripheral populations of Chihuahua chub in New Mexico, and compared these results to populations in Mexico including a new locality in the Rio Yaqui basin. All populations of Chihuahua chub in New Mexico were genetically depauperate as expected due to their small and peripheral status, and harbored distinct variation compared to those in Mexico. Allele and haplotype frequencies were divergent between New Mexican and Mexican populations, and mitochondrial haplotypes were not shared between them. All New Mexican populations were significantly divergent from one another suggesting little genetic exchange. New Mexican populations also exhibited relatively small genetic effective size. Chihuahua chub in New Mexico thus represent a unique component of the species’ evolutionary legacy and hence suggests high conservation value of this peripheral population. Conservation value of this population is bolstered by the fact that Chihuahua chub has more legal protection than counterparts in Mexico.

Copyright information

© Springer Science+Business Media B.V. 2012