Wild beluga whales can live for many decades: the oldest beluga on record had 80 growth layers in its teeth, which most researchers read as about 80 years, and NOAA Fisheries gives a lifespan of up to 90 years. That is roughly twice what many scientists believed before 2006.

These ages are estimates. Nobody has followed a wild beluga from birth to death; instead, scientists count layers in its teeth. The answer depends on how many layers a beluga adds each year, a question settled for most researchers by a 2006 study but still disputed by a minority.

Key facts about beluga lifespan

  • Oldest recorded: 80 growth layer groups (GLGs) in the teeth, possibly an underestimate because tooth wear erases early layers (NOAA Fisheries).
  • How ages are calibrated: a 2006 study using radiocarbon from Cold War nuclear tests found that belugas add one GLG per year, not two, and that GLG counts are accurate to at least 60 years.
  • The dispute: researchers studying known-age captive belugas argued in 2013 and 2018 that two layers form each year, which would halve age estimates.
  • Breeding: pregnancy lasts about 15 months; females reach sexual maturity at about 6–14 years of age (NOAA Fisheries).
  • Status: Least Concern globally on the IUCN Red List (2017 assessment), but Alaska’s Cook Inlet population is Critically Endangered (IUCN, assessed 2005) with about 331 whales (2022 survey).

How do scientists know how old a beluga is?

Beluga teeth grow in layers, a little like tree rings. Scientists count these growth layer groups (GLGs) in teeth taken from dead whales, such as animals killed in hunts.

The count is only half the problem. To turn layers into years, you need to know how often a layer forms. For decades, beluga researchers assumed two GLGs per year, unlike most other mammals, which are assumed to add one.

Worked example: why the layer rate matters

GLGs counted in a toothEstimated age at 1 GLG per year (years)Estimated age at 2 GLGs per year (years)
202010
404020
606030
808040

Calculation: age = GLG count ÷ layers per year. The 80-GLG row matches the oldest beluga reported by NOAA Fisheries.

The same tooth can therefore mean a 40-year-old or an 80-year-old whale. Researchers who still use the two-layer basis cite a lifespan of about 30 to 35 years, which is why older and newer sources disagree so widely.

What did the 2006 radiocarbon study find?

R.E.A. Stewart and colleagues, working with Fisheries and Oceans Canada, used a natural time stamp: atmospheric nuclear weapons tests in the 1950s and 1960s sharply raised radiocarbon levels in the environment. Belugas alive at the time locked that signal into the tooth layers forming that year.

The team measured radiocarbon in tooth layers from belugas harvested between 1895 and 2001. When they compared the radiocarbon dates with GLG counts, the layers matched one per year, not two, for belugas up to at least 60 years old. Their conclusion, published in the Canadian Journal of Zoology, was that belugas live about twice as long as previously thought. A 2014 review by two of the authors notes that bomb radiocarbon can age an individual to within about 1 to 3 years, provided the animal was alive in the 1960s.

Is the one-layer-a-year rule settled?

Not entirely. P. Brodie and colleagues compared growth and maturity in belugas of known age born or raised in aquariums. In a 2013 paper, they argued that the evidence supports two layers per year and that the radiocarbon results may have been affected by how teeth were prepared.

In 2018, Brodie and M. Haulena examined teeth from a mother and daughter that died at the Vancouver Aquarium in November 2016, aged 29.25 and 21.25 years. They reported two layers per year in both and argued that one-layer ages for old wild belugas are overestimates. NOAA Fisheries and NAMMCO, the North Atlantic Marine Mammal Commission, currently present ages on the one-layer basis, which is why this article does too. The disagreement matters for conservation: Brodie and colleagues calculate that the one-layer assumption implies a natural rate of population increase about 40% lower, which changes recovery targets.

Do belugas live longer in the wild or in captivity?

We could not find a peer-reviewed, beluga-specific comparison of survival in the wild and in captivity to cite, so we do not give one. The often-repeated claim that captive belugas “rarely reach 30” has no traceable source.

What exists are individual records of known-age captive animals, such as the Vancouver Aquarium pair above. Two animals cannot establish an average lifespan for either setting, and wild ages come from a different method entirely, so comparisons between them should be treated with caution.

A white beluga whale raising its head out of the water toward a keeper in a red jacket standing on a rocky pool edge
A beluga in an aquarium. Known-age captive belugas are at the centre of the debate over how fast tooth layers form.

What is the beluga life cycle?

A beluga calf is born after a pregnancy of about 15 months. Calves are brown or slate-grey at birth and lighten with age; NAMMCO reports that they become pure white after about 14 years in females and 18 years in males. Females typically give birth to one calf every two to three years.

Beluga ages at maturity are also read from teeth, so they carry the same uncertainty as lifespan. NOAA Fisheries puts sexual maturity in females at about 6 to 14 years, with males slightly older. Our article on what beluga whales eat covers their diet.

What threatens belugas and shortens their lives?

NOAA Fisheries lists climate change, contaminants, disease, habitat damage, harassment, ocean noise, predation, limited prey and strandings among the threats. Natural predators are killer whales and polar bears; see how many killer whales are left in the world for more on the beluga’s main ocean predator.

The St. Lawrence Estuary in Canada shows how threats interact. Canada’s wildlife status committee (COSEWIC) identified pathogens, toxic algal blooms, pollution and noise as major threats. A 2023 government science assessment found that survival of calves and pregnant females has been poor since 2010, while a falling incidence of cancers may have helped more older adults survive.

Are beluga whales endangered?

Not as a species. The IUCN Red List assessed the beluga as Least Concern in 2017, and NAMMCO estimates at least 200,000 belugas across the Arctic and sub-Arctic. Some populations, however, are in serious trouble.

PopulationStatusEstimated number (survey year)
Beluga, globalIUCN Least Concern (2017)At least 200,000 (NAMMCO, page updated 2024)
Cook Inlet, AlaskaIUCN Critically Endangered (assessed 2005); US Endangered Species Act, endangered since 2008331, range 290–386 (2022); about 1,300 in 1979
St. Lawrence Estuary, CanadaEndangered under Canada’s Species at Risk Act since 20171,850, 95% CI 1,500–2,200 (2022)

Sources: GBIF copy of the IUCN Red List dataset (Lowry, Reeves & Laidre 2017); NAMMCO; NOAA Fisheries (June 2023 Cook Inlet estimate); Federal Register, 20 April 2007 (IUCN Cook Inlet assessment); Fisheries and Oceans Canada Science Advisory Report 2023/024. The 2022 St. Lawrence estimate used updated correction factors that raise photographic-survey estimates 1.3 to 1.5 times, so it is not directly comparable with earlier figures of about 900–1,000.

Our page on whether beluga whales are endangered looks at these populations in more detail.

What scientists don’t know yet

  • Whether one or two tooth layers form each year in all populations and at all ages; most evidence points to one, but known-age captive studies disagree.
  • How long belugas live on average, as opposed to the maximum; tooth samples come mostly from harvested or stranded whales, which may not represent the whole population.
  • Whether the Cook Inlet population is now recovering; scientists say the overlap between the 2018 and 2022 estimates does not allow a firm conclusion.

Related reading

Update note: This article was substantially revised on October 12, 2026, to present beluga ages as tooth-layer estimates rather than measured “averages”, correct the description of the 2006 radiocarbon recalibration (from two layers per year to one), add the scientific dispute over that calibration, remove unsourced claims about captive lifespans, captive behaviour and “heavy metals”, and add IUCN and national statuses with dated population estimates. A link to an external sister site was removed. It was drafted with AI assistance and checked against the sources listed below.

Sources

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