Vertical migration in high Arctic waters during autumn 2004
2008
Abstract The
diel vertical migration(DVM) of zooplankton and pelagic fish in the southern
ArcticOcean (82°N) and in Rijpfjorden (Svalbard, Nordaustlandet, 80°N) was investigated in autumn 2004, when there were distinct differences in light conditions between
dayand
night. We collected data on zooplankton and fish distribution using plankton nets, trawls, and an echo sounder together with data on environmental parameters including sea-ice distribution,
hydrography, and in situ fluorescence in the water column. In Rijpfjorden, the
Arcticphytoplankton bloom had culminated several weeks prior to the present study and all three
Calanusspecies had migrated down to depths for over wintering and did not show any changes in vertical distribution. However, in the
ArcticOcean pack ice at 82°N,
Calanus hyperboreus, was found in high abundances (up to 65 ind. m −3 ) actively feeding on the
Arcticbloom in September. They performed a classic DVM, feeding in the upper 50 m during the night and descending to depths below 50 m during the day. In Rijpfjorden, distinct DVM patterns were observed among the amphipod
Themisto libellula, adult and juvenile stages of the pteropod
Limacina helicina, and polar cod. Polar cod in Rijpfjorden fed on
Calanusspp. and on L.
helicina. We conclude that animals display DVM in the
Arcticduring autumn if they need to feed in food-rich surface waters.
Keywords:
-
Correction
-
Source
-
Cite
-
Save
35
References
64
Citations
NaN
KQI