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P23. Active predation by Greenland shark Somniosus microcephalus
Julius Nielsen 1,2 , Rasmus Hedeholm 1 , Malene Simon 1 og John Fleng Steffensen 2
1
Grønlands Naturinstitut, P.O. Boks 570, 3900 Nuuk. juliusnielsen88@gmail.com, rahe@natur.gl,
masi@natur.gl
2
Marinbiologisk laboratorium, Strandpromenaden 5, 3000 Helsingør. jfsteffensen@bio.ku.dk
The Greenland shark is ubiquitous in the northern part of the North Atlantic ranging from eastern
Canada to northwest Russia . Although knowledge is scarce it is believed to be abundant and
potentially important part of the ecosystem. Whether Greenland sharks in general should be
considered opportunistic scavengers or active predators is therefore important in understanding
ecosystem dynamics. Due to its sluggish appearance and a maximum reported swimming speed of
74 cm per second scavenging seems the most likely feeding strategy. However, recent studies
suggest that Greenland sharks in some areas feed actively upon seals .
Feeding ecology is poorly described in Greenland waters. In this study we provide information on
feeding habits of 29 sharks caught in Greenland waters in the summer 2012 and show that the
sharks catch epi-benthic species with Atlantic cod being the most important (% IRI = 56 ),
followed by squid (% IRI= 13 ) and wolf fish (IRI=4). Furthermore seal was found in 50 % of all
stomachs (% IRI= 13).
In addition to providing new knowledge of feeding habits of this species in Greenland waters, we
suggest the results show that the Greenland catches the majority of its prey by active predation.
Program 17. danske havforskermøde, 140