Errors are feared in carbon dating
They appear to grow extremely slowly — less than one centimetre per year — and are believed to not reach maturity until females are 4.5 metres long and males are three metres long. Scientists recently used radiocarbon dating techniques on the eye lens of a Greenland shark, and found they can live for more than 272 years, making the species the longest living vertebrate on the planet.While these are impressive traits, their age and large size leave Greenland sharks more vulnerable to stressors such as overfishing or habitat loss than other fishes.
This area is known as a vital feeding and nursery ground for many Arctic species of both ecological and Inuit cultural significance, including whales, seabirds, polar bears, seals and walruses.
Our video data now shows that this area might of be important to Greenland sharks too, at least in summer months.
Scientists know little about Greenland sharks living in the unfished waters of the eastern Canadian Arctic.
To help collect information on sharks residing in this region, we baited cameras with squid and dropped them into the deep waters of Nunavut.
And yet these fish, which prefer the deep, cold waters of the Arctic and North Atlantic oceans, have largely eluded scientific study.
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Their evasiveness highlights how little we know about Arctic marine ecosystems — and how much we can learn by developing and employing new technologies.Due to their sluggish and seemingly lethargic behaviour, the Greenland shark is part of the family of “sleeper sharks.” Despite being remarkably slow swimmers and effectively blind, thanks to eye parasites, the Greenland shark is one of the Arctic’s top predators.Although they feed mostly on a diverse buffet of bottom-dwelling fishes, there is some evidence that they can capture live seals.Jonathan Fisher receives funding from the Natural Sciences and Engineering Research Council of Canada and the Ocean Frontier Institute (OFI; The OFI was established within the Canada First Research Excellence Fund.Until now, most of what we knew about Greenland sharks came from the historical records of commercial landings.They were fished in the North Atlantic for their oily livers until 1960.Just how they catch these fast-swimming marine mammals, remains a mystery to researchers.Greenland sharks are by far the largest fish in the Arctic.For scientists like us, the observation and monitoring of marine species can be challenging under the best of circumstances.But sampling at extreme depths and in seasonally ice-covered waters is especially difficult.