MEPS

Marine Ecology Progress Series

MEPS is a leading hybrid research journal on all aspects of marine, coastal and estuarine ecology. Priority is given to outstanding research that advances our ecological understanding.

Online: ISSN 1616-1599

Print: ISSN 0171-8630

DOI: https://doi.org/10.3354/meps

Volume contents
Mar Ecol Prog Ser 677:1-16 (2021)

Seasonal variations in migration strategy of a long-distance Arctic-breeding seabird

ABSTRACT: Long-distance migratory seabirds need to adjust their migration strategy according to internal (breeding, molting) and external factors (seasonality, resource availability). Time-minimizing strategies are common during spring migration to arrive at the optimal time to breed. We studied the annual movements and migration strategy of the long-tailed jaeger Stercorarius longicaudus, a small arctic-nesting seabird. First, we documented year-round movements (routes, wintering sites) of male and female jaegers breeding in the Canadian Arctic. We then compared their migration strategies between seasons (phenology, stopover use, travel distance, speed) to determine whether they adopt a time-minimizing strategy in spring. Over 6 yr, we collected 43 tracks from geolocators deployed on Bylot and Igloolik Islands. Jaegers departed the breeding site over a 5 wk period and traveled on average 32375 km (round trip) before returning to breed, one of the longest documented migrations on Earth. Birds used a major stopover area east of the Grand Banks of Newfoundland in spring and fall, and wintered in high marine productivity areas of the South Atlantic. Unexpectedly, the spring migration was 40% longer and 32% slower than in fall, and birds increased their time spent on water (foraging and/or resting) by 61%. A time-minimizing strategy in fall may help to reach the wintering site rapidly and start molting early. In spring, a fly-and-forage strategy seems to be adopted to increase foraging effort, probably for the accumulation of body reserves before breeding and in anticipation of unfavorable conditions that may prevail at arrival on their arctic breeding site.

KEYWORDS

Migratory behavior in seabirds can be affected by factors like breeding, molting, seasonality, and resource availability. Using geolocators, Seyer and co-workers revealed for the first time the complete, annual, long-distance migratory movements of long-tailed jaegers breeding in the Canadian Arctic. Jaegers traveled on average >32,000 km per year, wintering across a wide region of the southern Atlantic. Contrary to most other bird species, jaegers’ prebreeding migration was 40% longer and 32% slower than postbreeding migration. While jaegers used a postbreeding time-minimizing strategy to rapidly reach the wintering sites, most likely to molt, they adopted a fly-and-forage strategy during prebreeding migration, slowing it down and increasing foraging effort, probably to accumulate body reserves in anticipation of unfavorable conditions on arrival at breeding sites.

Yannick Seyer (Corresponding Author)

  • Département de biologie and Centre d’études nordiques, Université Laval, Québec, QC G1V 0A6, Canada
yannick.seyer.1@ulaval.ca

Gilles Gauthier (Co-author)

  • Département de biologie and Centre d’études nordiques, Université Laval, Québec, QC G1V 0A6, Canada

Joël Bêty (Co-author)

  • Département de Biologie and Centre d’études nordiques, Université du Québec à Rimouski, Rimouski, QC G5L 3A1, Canada

Jean-François Therrien (Co-author)

  • Acopian Center for Conservation Learning, Hawk Mountain Sanctuary, Orwigsburg, PA 17961, USA

Nicolas Lecomte (Co-author)

  • Centre d’études nordiques and Department of Biology, University of Moncton, Moncton, NB E1A 3E9, Canada