Leucocyte profiles of Arctic marine birds: correlates of migration and breeding phenology.
Most Arctic marine birds are migratory, wintering south of the limit of annual pack ice and returning north each year for the physiologically stressful breeding season. The Arctic environment is changing rapidly due to global warming and anthropogenic activities, which may influence the timing of breeding in relation to arrival times following migration, as well as providing additional stressors (e.g. disturbance from ships) to which birds may respond. During stressful parts of their annual cycle, such as breeding, birds may reallocate resources so that they have increased heterophil-to-lymphocyte ratios in their white blood cell (leucocyte) profiles. We analysed leucocyte profiles of nine species of marine birds to establish reference ranges for these species in advance of future Arctic change. Leucocyte profiles tended to cluster among taxonomic groups across studies, suggesting that reference values for a particular group can be established, and within species there was evidence that birds from colonies that had to migrate farther had higher heterophil-to-lymphocyte ratios during incubation than those that did not have to travel as far, particularly for species with high wing loading.
Department of Biology, Acadia University, Wolfville, NS, Canada B4P 2R6.
Mark L
ML
Mallory
Department of Biology, Acadia University, Wolfville, NS, Canada B4P 2R6.
Catherine M
CM
Little
Department of Biology, Acadia University, Wolfville, NS, Canada B4P 2R6.
Ellen S
ES
Boyd
Southeastern Cooperative Wildlife Disease Study, University of Georgia, 589 DW Brooks Drive, Athens, GA 30680, USA.
Jennifer
J
Ballard
Natural Resource Sciences, McGill University, Ste. Anne de Bellevue, QC, Canada H9Z 3V9.
Kyle H
KH
Elliott
Wildlife Research Division, Environment Canada, National Wildlife Research Centre, Carleton University, Raven Road, Ottawa, ON, Canada K1A 0H3.
H Grant
HG
Gilchrist
Wildlife Research Division, Environment Canada, 5421 Robertson Road, Delta, BC, Canada V4K 3N2.
J Mark
JM
Hipfner
Brautarland 2, 108 Reykjavik, Iceland.
Aevar
A
Petersen
Department of Biology, Acadia University, Wolfville, NS, Canada B4P 2R6.
Dave
D
Shutler
Heterophil; leucocyte; lymphocyte; marine bird; stress