Access

You are not currently logged in.

Access JSTOR through your library or other institution:

login

Log in through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Journal Article

Allozyme Variation among Breeding Populations of Red-Winged Blackbirds: The California Conundrum

Thomas A. Gavin, Ronald A. Howard and Bernie May
The Auk
Vol. 108, No. 3 (Jul., 1991), pp. 602-611
DOI: 10.2307/4088101
Stable URL: http://www.jstor.org/stable/4088101
Page Count: 10
Were these topics helpful?
See something inaccurate? Let us know!

Select the topics that are inaccurate.

Cancel
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Add to My Lists
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Allozyme Variation among Breeding Populations of Red-Winged Blackbirds: The California Conundrum
Preview not available

Abstract

We examined allozyme variation in 10 breeding populations of Red-winged Blackbirds (Agelaius phoeniceus) across the United States, which represented samples from 9 of 14 putative subspecies in North America. Variation at 13 of 28 resolvable loci revealed a high level of genetic similarity for all seven populations from Florida and New York through the Great Plains to Oregon and northeastern California (pairwise Nei's distances, all ≤0.004). Differences in allozyme frequencies we found suggest that fewer subspecies exist in the continental United States than are currently recognized. The most interesting result was that the genetic distance between the populations sampled at Sacramento and San Francisco Bay national wildlife refuges, which are only 214 km apart, had a Nei's distance approximately 10 times as great as the genetic distance between Florida and Oregon populations. Salton Sea, California, the remaining population sampled, was also highly differentiated. Strong site fidelity, the nonmigratory behavior of populations at Salton Sea and San Francisco, or both probably explain their relative allozyme distinctness, but the possibility that the brackish environment in which these birds live enforces a selective regime that reduces successful immigration or emigration to other habitats is intriguing.

Page Thumbnails

  • Thumbnail: Page 
602
    602
  • Thumbnail: Page 
603
    603
  • Thumbnail: Page 
604
    604
  • Thumbnail: Page 
605
    605
  • Thumbnail: Page 
606
    606
  • Thumbnail: Page 
607
    607
  • Thumbnail: Page 
608
    608
  • Thumbnail: Page 
609
    609
  • Thumbnail: Page 
610
    610
  • Thumbnail: Page 
611
    611