Skip to main content
Article
Regional genetic structure in the Magellanic penguin (Spheniscus magellanicus) suggests metapopulation dynamics
Auk
  • Juan L. Bouzat
  • Brian G. Walker, Fairfield University
  • P. Dee Boersma
Document Type
Article
Article Version
Publisher's PDF
Publication Date
1-1-2009
Disciplines
Abstract
Using microsatellite markers and mitochondrial DNA (mtDNA) sequences (cytochrome oxidase 1 gene), we estimated levels of genetic structuring among nine Magellanic Penguin (Spheniscus magellanicus) colonies distributed throughout three major reproductive regions of the South Atlantic Ocean. Overall, breeding colonies showed relatively high levels of genetic diversity at both nuclear and mtDNA markers (mean heteorzygosity: He = 0.598; mean allelic diversity: A = 7.11; mtDNA haplotype diversity: h = 0.812). A hierarchical analysis of molecular variance based on microsatellite data showed limited genetic structuring of breeding colonies, with 99% of the variation explained by differences among individuals and 0.7–1.0% attributed to differences among the three regions. The mtDNA analysis revealed higher levels of genetic structuring, with 3.43% of the variation explained by regions and 2.24% explained by colonies within the regions. Furthermore, a Mantel test revealed a significant association between geographic and genetic distances among colonies. The limited genetic structuring we detected is likely a result of (1) population intermixing through natal dispersal and (2) the large effective sizes of the reproductive colonies, both of which prevent genetic differentiation at neutral markers, balanced with (3) the regional association of breeding colonies to distinct feeding grounds and (4) a recent expansion of the population. Our results suggest that the demographic dynamics of breeding colonies of Magellanic Penguins may be framed under a metapopulation model, in which colonies with large numbers of breeding pairs could be considered "source" populations for maintaining the overall abundance of this species in the Atlantic Ocean.
Comments

Copyright 2009 University of California Press for American Ornithologists' Union (AOU).

This article is also electronically available via Caliber, JSTOR and AnthroSource.

Published Citation
Bouzat, JL, BG Walker and PD Boersma. 2009. Regional genetic structure in the Magellanic penguin (Spheniscus magellanicus) suggests metapopulation dynamics. Auk 126 (2):326-334.
DOI
10.1525/auk.2009.07122
None
Peer Reviewed
Citation Information
Juan L. Bouzat, Brian G. Walker and P. Dee Boersma. "Regional genetic structure in the Magellanic penguin (Spheniscus magellanicus) suggests metapopulation dynamics" Auk Vol. 126 Iss. 2 (2009)
Available at: http://works.bepress.com/juan_bouzat/2/