2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

-6 and -10 in vertebrate model organisms. We found conserved synteny indicating
that the origin of Pax10 was part of a large-scale duplication event. Thus, Pax10 is
presumably the third identified member of the original gene quartet generated by
the two rounds of whole-genome duplication that occurred in the ancestral
vertebrate genome. An analysis of the expression patterns of Pax10 genes in
zebrafish, Xenopus and anole lizard using in situ hybridizations and quantitative RT-
PCR showed that Pax10 expression patterns differed between three different
vertebrate classes and revealed secondary changes in developmental roles between
the three sister genes Pax4, -6 and -10.
Award IMPRS Best Student Paper Award M 629 / 17:15
POSTERS
����218 Andrea Gehrold
Seasonal flexibility in a European migrant, the Gadwall (Anas strepera)
Authors: Andrea Gehrold 1 , Hans-Günther Bauer 1 , Wolfgang Fiedler 1 , Martin
Wikelski 1
Affiliation: 1 Max Planck Institute for Ornithology
During the last decades, the number of Gadwalls (Anas strepera) has been
continuously increasing in western Europe, supposedly in response to the
eutrophication of wetlands and the creation of water impoundments. The potential
of migratory birds to discover habitats of suitable quality may, however, depend on
the narrowness of migratory routes.
To measure movement behaviour and range, 17 adult Gadwalls were equipped with
backpack satellite transmitters and continuously tracked during different stages of
their annual cycle. Furthermore, we analyzed direct autumn and winter recoveries of
327 Gadwalls ringed during summer in Germany, western Russia, and England -
therefore representing birds from the three known European flyway populations. The
migration of tracked individuals was target-oriented and short in time, although
bearings differed remarkably. Birds spent some months at the breeding and moulting
site, but stopover times significantly decreased in autumn and early winter. During
the latter period, Gadwalls also tended to visit multiple sites and to perform reverse
migrations. Similarly, ring recoveries revealed that movement directions were highly
variable from August to October. Some individuals even travelled hundreds of
kilometres in northern directions, obviously moving away from subsequent wintering
sites. Our results indicate that Gadwalls may perform complex movements during
autumn, the time of the year when they are to some extent released from
environmental and fitness-relevant constraints. Flexible migration strategies may
enable birds to find, evaluate, and adopt habitats of improved quality which holds
important implications for the conservation and management of wetlands and duck
populations.
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