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.