Autumn movements of fin whales (Balaenoptera physalus) from Svalbard, Norway, revealed by satellite tracking
Résumé
Insight into animal movements is essential for understanding habitat use by individuals as well
as population processes and species life-history strategies. In this study, we instrumented 25 fin
whales with ARGOS satellite-transmitters in Svalbard, Norway, to study their movement patterns
and behaviour (Area Restricted Search (ARS), transiting or unknown) during boreal autumn/early
winter. Ten of the whales stayed in the tagging area (most northerly location: 81.68°N) for their entire
tracking periods (max 45 days). The other 15 whales moved in a south-westerly direction; the longest
track ended off the coast of northern Africa (> 5000 km from the tagging location) after 96 days. The
whales engaged in ARS behaviour intermittently throughout their southward migrations. During
transit phases the whales moved quickly; one individual maintained an average horizontal speed of
9.3 km/h (travelling 223 km per day) for a period of a week. This study documents that: (1) some fin
whales might remain at high latitudes during winter; (2) the whales that do migrate probably feed
along the way; (3) they can maintain high transiting speed for long periods and; (4) one breeding area
for this species is likely located in deep, warm water some 100 km west of Morocco.