Diving behaviour of hooded seals (Cystophora cristata) in the Greenland and Norwegian Seas

Citation
Lp. Folkow et As. Blix, Diving behaviour of hooded seals (Cystophora cristata) in the Greenland and Norwegian Seas, POLAR BIOL, 22(1), 1999, pp. 61-74
Citations number
62
Categorie Soggetti
Biology
Journal title
POLAR BIOLOGY
ISSN journal
07224060 → ACNP
Volume
22
Issue
1
Year of publication
1999
Pages
61 - 74
Database
ISI
SICI code
0722-4060(199907)22:1<61:DBOHS(>2.0.ZU;2-T
Abstract
Satellite-linked dive recorders were used to collect data on depths and dur ations of similar to 120,000 dives by 16 hooded seals (Cystophora cristata) . Following tagging after moult (four males, eight females) and breeding (f our females) off east Greenland, seals dispersed widely in the northeast At lantic during 172 +/- 97 days (mean satellite-linked dive recorder lifetime +/- SD). Meso/bathypelagic dives of 5- to 25-min duration to 100-600 m dom inated (75%), but some very deep (greater than or equal to 1016 m) and long (>52 min) dives occurred. Diving in open ocean was continuous, with an est imated 90.7 +/- 0.8% (mean +/- SE) of time spent submerged. The proportion of time spent submerged was similar during night and day, but dives during the day were generally deeper and longer (P < 0.05) than during the night. Also, dives in winter were deeper and longer than in summer. Published data on the distribution of likely prey suggest that Greenland halibut (Reinhar dtius hippoglossoides), redfish (Sebastes spp.), polar cod (Boreogadus said a), herring (Clupea harengus), squid (Gonatus fabricii) and blue whiting (M icromesistius poutassou) are important prey of hooded seals.