5 other facts about the Greenland shark

Scientists recently discovered that the Greenland shark (Somniosus microcephalus) has a life expectancy of at least 272 years, giving it “the longest life expectancy of all vertebrate animals known to science.”

Greenland shark. Photo credit: Julius Nielsen, University of Copenhagen.

Fish can be aged many ways, including size estimates and by counting rings in otoliths (ear bones). Greenland sharks, however, posed a trickier problem. Scientists ended up using the Greenland shark’s eye lense and Carbon-14 dating (typically used in archaeology). Read more about that process here!

The oldest shark sampled in this study was 392 plus or minus 120 years, which is why all the headlines are talking about 400 year old sharks. They could be even older than that!

Now that we know they live for centuries, here are a few other facts about the Greenland shark:

1. They are one of the world’s largest species of sharks, reaching lengths of up to 5 meters (16.4 ft) in length. They grow slowly, though, gaining only a few centimeters over the course of a few years.
2. They don’t start reproducing for more than a century. They reach sexual maturity around age 150. Females give birth to about 10 pups at a time, which reach about 38 cm in length.
3. Greenland sharks aren’t well known — the first underwater photos of a live individual were taken in the Arctic in 1995 and the first video footage wasn’t taken until 2003.
4. The Greenland shark lives in the cold waters of the northern Atlantic and Arctic. It is one of only two sharks that can tolerate Arctic temperatures year round. The other is the Pacific sleeper shark, Somniosus pacificus.
5. They are some of the slowest sharks in the world, averaging about one mile per hour.

To learn more:

• Read the news release: Greenland sharks live for hundreds of years
• Read the full Greenland shark aging study: Eye lens radiocarbon reveals centuries of longevity in the Greenland shark (Somniosus microcephalus)

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