PARASITES
The parasite most commonly associated with the Greenland shark is the copepod Ommatokoita elongata. It latches itself to one or both of the shark's eyes which causes lesions to the cornea and can render the shark partly blind. However, even if it was completely sightless, the Greenland shark could easily survive using its other senses to detect and localise prey.
Also, since the shark lives at great depth and often under ice, its habitat is normally devoid of light rendering its eyes useless. Certain researchers believe the copepod is bioluminescent and serves to attract prey to the shark but this has never been proven. It is interesting to note that while over 90% of Arctic populations of the Greenland shark parasited by the copepod, less than 10% of the sharks encountered by GEERG researchers in the St. Lawrence are hosts of Ommatokoita elongata.
In 2004, GEERG researcher Jeffrey Gallant observed a sea lamprey (Petromyzon marinus) parasiting a Greenland shark near Baie-Comeau, in the St. Lawrence Estuary. (See science paper* in Publications section)
* Gallant, J., C. Harvey-Clark, R.A. Myers, and M.J.W. Stokesbury. 2005. Sea lamprey (Petromyzon marinus) attached to a Greenland shark (Somniosus microcephalus) in the St. Lawrence Estuary, Canada. Northeastern Naturalist. 2006 13(1):35–38.
PARASITESThe parasite most commonly associated with the Greenland shark is the copepod Ommatokoita elongata. It latches itself to one or both of the shark's eyes which causes lesions to the cornea and can render the shark partly blind. However, even if it was completely sightless, the Greenland shark could easily survive using its other senses to detect and localise prey. Also, since the shark lives at great depth and often under ice, its habitat is normally devoid of light rendering its eyes useless. Certain researchers believe the copepod is bioluminescent and serves to attract prey to the shark but this has never been proven. It is interesting to note that while over 90% of Arctic populations of the Greenland shark parasited by the copepod, less than 10% of the sharks encountered by GEERG researchers in the St. Lawrence are hosts of Ommatokoita elongata. In 2004, GEERG researcher Jeffrey Gallant observed a sea lamprey (Petromyzon marinus) parasiting a Greenland shark near Baie-Comeau, in the St. Lawrence Estuary. (See science paper* in Publications section) * Gallant, J., C. Harvey-Clark, R.A. Myers, and M.J.W. Stokesbury. 2005. Sea lamprey (Petromyzon marinus) attached to a Greenland shark (Somniosus microcephalus) in the St. Lawrence Estuary, Canada. Northeastern Naturalist. 2006 13(1):35–38.
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