Breeding latitude drives individual schedules in a trans-hemispheric migrant bird.
Despite clear benefits of optimal arrival time on breeding grounds, migration schedules may vary with an individual bird's innate quality, non-breeding habitat or breeding destination. Here, we show that for the bar-tailed godwit (Limosa lapponica baueri), a shorebird that makes the longest known non-stop migratory flights of any bird, timing of migration for individual birds from a non-breeding site in New Zealand was strongly correlated with their specific breeding latitudes in Alaska, USA, a 16,000-18,000 km journey away. Furthermore, this variation carried over even to the southbound return migration, 6 months later, with birds returning to New Zealand in approximately the same order in which they departed. These tightly scheduled movements on a global scale suggest endogenously controlled routines, with breeding site as the primary driver of temporal variation throughout the annual cycle.
Conklin
Jesse R
JR
Ecology Group, Institute of Natural Resources, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand. conklin.jesse@gmail.com
Battley
Phil F
PF
Potter
Murray A
MA
Fox
James W
JW
D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D001717:Birds; D001947:Breeding; D017753:Ecosystem; D009520:New Zealand; D014481:United States