Sympatrically-breeding congeneric seabirds (Stercorarius spp.) from Arctic Canada migrate to four oceans

Polar systems of avian migration remain unpredictable. For seabirds
nesting in the Nearctic, it is often difficult to predict which of the
world’s oceans birds will migrate to after breeding. Here we report on
three related seabird species that migrated across four oceans following
sympatric breeding at a central Canadian high Arctic nesting location.
Using telemetry we tracked pomarine jaeger (Stercorarius pomarinus, n=1)
to the Arctic Ocean to the western Pacific Ocean; parasitic jaeger (S.
parasiticus, n=4) to the western Atlantic Ocean, and long-tailed jaeger
(S. longicaudus, n=2) to the eastern Atlantic Ocean and western Indian
Ocean. We also report on extensive nomadic movements over ocean during the
post-breeding period (19,002 km) and over land and ocean during the
pre-breeding period (5,578 km) by pomarine jaeger, an irruptive species
whose full migrations and nomadic behavior have been a mystery. While the
small sample sizes in our study limit the ability to make generalizable
inferences, our results provide a key input to the knowledge of jaeger
migrations. Understanding the routes and migratory divides of birds
nesting in the Arctic region has implications for understanding both the
glacial refugia of the past and the Anthropocene-driven changes in the
future.