Meeting Abstract

S10.8  Tuesday, Jan. 6  Physiological control of non-seasonal reproduction: opportunistic breeding PERFITO, Nicole*; ZANN, Richard A.; HAU, Michaela; BENTLEY, George E.; Univ. of California, Berkeley; LaTrobe University, Melbourne, Australia; Max Planck Institute for Ornithology, Radolfzell, Germany; Univ. of California, Berkeley nperfito@berkeley.edu

Zebra finches Taeniopygia guttata range over most of the Australian continent inhabiting a diverse range of habitat and climate. The species has long been the prototypical example for opportunistic breeding, able to take advantage of good conditions whenever they occur, but there have been few physiological data collected on wild birds. We have shown that the extent to which zebra finch physiology conforms to expectations for opportunistic breeders depends on habitat predictability. Birds in less predictable habitats of the arid interior maintain their reproductive systems in a near-ready state even during bouts of non-breeding, while birds in more predictable habitats of the temperate south show seasonal cycles in reproductive parameters. Here we consider the potential neuroendocrine mechanisms underlying transitions between breeding and non-breeding states, specifically by measuring three peptides in the brain (gonadotropin-releasing hormone-I, -II and gonadotropin-inhibitory hormone) involved in regulating reproduction. We will also discuss preliminary data testing whether GnRH-II plays an important role in responding to social signals to maintain physiological synchrony between mates.