Greenland sharks, the slow-moving predators of the deep Arctic, can live for at least 272 years and possibly close to four centuries, according to radiocarbon dating of eye-lens proteins from 28 female specimens. That makes them the longest-lived vertebrate species ever documented. Their extreme lifespan, paired with sexual maturity that arrives only around 150 years of age, raises pointed questions about how well current fisheries management protects an animal that needs more than a century just to begin reproducing.
Why centuries-long shark lifespans demand attention now
The core finding comes from a peer-reviewed study led by Julius Nielsen and published in a Science journal analysis, which used radiocarbon signatures trapped in the eye-lens nuclei of 28 female Greenland sharks (Somniosus microcephalus). Because the lens nucleus forms before birth and does not undergo protein turnover afterward, it preserves a chemical timestamp of the surrounding ocean carbon at the time the shark was born. By calibrating those signals against the bomb-pulse radiocarbon spike from mid-twentieth-century nuclear testing, the research team estimated that the largest specimen, measuring roughly five meters, was approximately 392 years old. The uncertainty range on that figure is wide, but even the most conservative reading puts the minimum lifespan at about 272 years.
NOAA’s Ocean Service adopted a rounded but still striking threshold, describing the species as having a lifespan of at least 250 years and calling it the longest-lived vertebrate known. That institutional endorsement moved the finding from a single journal paper into the baseline reference material used by fisheries managers and conservation planners, effectively locking Greenland sharks into the small group of marine animals whose biology forces regulators to think in centuries rather than decades.
The hypothesis that such longevity tracks with metabolic suppression rather than body size alone is gaining traction in aging research. A study published in Aging Cell examined cardiac resilience in the Greenland shark, using the accepted lifespan and maturity estimates to explore how the species maintains heart function across centuries. If stable lens-protein turnover rates could be measured across other cold-water shark species, researchers could begin testing whether slow metabolism is the primary driver of extreme vertebrate age or whether other mechanisms, such as DNA repair efficiency, play a larger role.
Radiocarbon dating and the 28-shark dataset
The strength of the Science paper rests on a technique borrowed from forensic science and adapted for marine biology. Eye-lens radiocarbon dating had previously been applied to whales and bony fish, but Nielsen’s team was the first to apply it systematically to a shark species. The 28 females in the study ranged widely in size, allowing the researchers to build an age-length curve that connects body length with estimated age. Smaller sharks born after the early 1960s carried the distinctive carbon-14 spike from atmospheric nuclear tests, which served as a built-in calibration point. Larger sharks lacked that spike entirely, placing their births well before the nuclear era and, in several cases, centuries earlier.
The 392-year upper estimate drew headlines, but the team was careful to flag the wide confidence interval surrounding it. The 272-year conservative minimum is the figure that carries the most analytical weight because it sits at the lower bound of the statistical model. Even at that floor, the Greenland shark surpasses the bowhead whale, previously considered the longest-lived vertebrate at roughly 200 years. The analysis also suggested that growth rates are extraordinarily slow, with individuals adding only a few millimeters per year, reinforcing the picture of a species that lives on geologic time.
Sexual maturity arriving at around 150 years adds a conservation dimension that goes beyond biological curiosity. A species that cannot reproduce for a century and a half is acutely sensitive to any source of adult mortality. Bycatch in Arctic and sub-Arctic fisheries is the most immediate threat. Greenland sharks are frequently caught in trawls and longlines targeting halibut and shrimp. Because the sharks have little commercial value, they are typically discarded, but post-release survival rates are poorly documented, and even low annual mortality could have outsized effects when individuals take generations to replace themselves.
Gaps in bycatch data and male age structure
The 2016 dataset covers only females. No equivalent age-structure analysis exists for male Greenland sharks, leaving open the question of whether males reach comparable ages or mature on a different timeline. That gap matters for population modeling: without sex-specific age data, estimates of reproductive output, sex ratios among mature animals, and recovery potential remain rough. If males mature earlier or suffer higher fishing mortality, the breeding population could be skewed in ways that current models do not capture.
Bycatch figures present a similar blind spot. A concise Nature commentary flagged the conservation risk created by delayed maturity, noting that fishing mortality could remove individuals that have not yet contributed offspring to the population. Yet no published dataset quantifies how many Greenland sharks are caught and discarded each year across Arctic fisheries. Observer coverage is limited in many high-latitude fleets, and reporting categories often lump multiple shark species together, making it difficult to extract species-specific trends.
NOAA’s general explanations of bycatch emphasize that many non-target species die after being hooked or entangled, even when released, but they do not provide detailed tallies for Greenland sharks. Without those numbers, managers cannot easily determine whether current fishing pressure is compatible with the species’ life history. A population in which most individuals die before reaching 150 years of age would be functionally non-reproductive, even if thousands of juveniles are present.
The Aging Cell paper on cardiac resilience restates the accepted longevity and maturity benchmarks but does not introduce new field sampling or updated age estimates. That means the 392-year upper bound and the 272-year lower bound from the original Science paper remain the best available numbers years after publication. Fresh sampling, particularly of males and of sharks from different geographic populations, would sharpen the picture considerably and test whether the age-length relationship holds across the species’ range.
Implications for Arctic fisheries management
For regulators, the message embedded in the Greenland shark’s biology is stark. Management frameworks built around annual quotas and short-term stock assessments are poorly matched to a species that may not replace a lost adult for more than a century. Precautionary measures, such as gear modifications that reduce shark bycatch, time-area closures in known hotspot regions, and mandatory live-release protocols, become more urgent when each mature individual represents centuries of survival.
International coordination is also critical. Greenland sharks move across national boundaries in the North Atlantic and Arctic, encountering fleets governed by different rules. Without shared bycatch monitoring standards and compatible data systems, conservation efforts in one jurisdiction can be undermined by unreported mortality in another. The absence of robust male age data and species-specific bycatch statistics compounds this problem, leaving decision-makers to work with broad assumptions rather than precise estimates.
Ultimately, the discovery that Greenland sharks can outlive entire human political eras forces a reconsideration of what sustainable use means in the far north. Protecting a vertebrate that may have been born before the industrial revolution will require management horizons that extend well beyond typical planning cycles. Until better data arrive, the combination of extreme longevity, late maturity, and unquantified bycatch argues for treating Greenland sharks not as curiosities of the deep, but as test cases for whether modern fisheries policy can accommodate life histories measured in centuries.
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*This article was researched with the help of AI, with human editors creating the final content.
