Protogyny in Autumn Migration: Do Male Birds "Play Chicken"?

From Pubwiki

[edit] Author(s)

• Mills, A. M.

[edit] Journal

Auk 122.1 (2005): 71-81.

[edit] Keywords

banding differential migration long-distance migrants long point bird observatory mate choice protandry protogyny short-distance migrants territoriality winter ecology swallow hirundo-rustica black grouse males spring migration neotropical migrant american redstarts breeding grounds sexual selection stable-isotopes site fidelity arrival times

[edit] Abstract

Protandry, the earlier arrival of males than of females on breeding areas, occurs in many taxa, including many migratory birds. Numerous hypotheses have been generated to explain protandry. Using bird-banding records, I show that protogyny, the earlier migration of females, frequently occurs in the autumn, though it is less universal and less dramatic than spring protandry. In one species, it occurs in both hatch-year and adult birds. When (1) spring and autumn, (2) departures and arrivals, and (3) breeding and wintering ground conditions are considered, hypotheses generated only to explain spring protandry can be more thoroughly evaluated. Using that approach, the most parsimonious explanation of differential migration between the sexes explains earlier male arrival in spring and later male departure in autumn through either (1) indirect selection operating on intrasexual male competition for territories or (2) direct selection operating on intersexual relations requiring males to be present on breeding territories when females are present. In autumn-protogynous species, males may "play chicken," balancing the benefits of remaining longer than females and protecting territories for subsequent years against the costs of remaining in the north under deteriorating conditions and delaying the acquisition of a good winter territory.

[edit] Complete Publication (PDF; password required)

If you would like to join MIGRATE to get access to this publication, please email us!