Greenland Shark - Life History

Life History

The Greenland shark is an apex predator mostly eating fish. Recorded fish prey have included smaller sharks, skates, eels, herring, capelin, char, cod, redfish, sculpins, lumpfish, wolfish and flounders. However, it may also prey on marine mammals such as seals. Bite marks on dead seals at Sable Island, Nova Scotia and Hawarden suggest that this shark may be a major predator for them in the winter months. Greenland sharks have also been found with remains of polar bear, horses and reindeer (in one case an entire reindeer body was found in the shark's stomach) in their stomachs. The Greenland shark is also known to be a scavenger but to what extent carrion (almost certainly the origin of the reindeer) figures into the slow-moving fish's stomach contents is unknown. It is known, however, that the species is attracted by the smell of rotting meat in the water. They often congregate in large numbers around fishing operations. The shark is colonized by the parasitic copepod Ommatokoita elongata that eats the shark's corneal tissue. It has been reported that this parasite is bioluminescent and gives the shark a greenish glow around the eye when seen in dark waters but this has not been scientifically supported. The shark occupies what tends to be a very deep environment seeking its preferable cold water (-0.6 to 10 °C (31 to 50 °F)) habitat. It has been observed at a depth of 2,200 m (7,200 ft) by a submersible investigating the wreck of the SS Central America. A specimen video-taped at 2,773 m (9,098 ft) off the coast of Brazil on February 11, 2012 may have been a Greenland shark, but cannot be distinguished in the video from a southern sleeper shark or Pacific sleeper shark. However, a more typical depth for the species is above 1,200 m (3,900 ft). Frequently during the winter, when the sharks look for warmer waters to inhabit, they often found at or near the surface of the water.

As ectotherms, the Greenland shark is slow, cruising at 1 mph with a top speed of 1.6 mph.