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Orca found dead on South Uist identified as one of the oldest males ever recorded
Overview
Scientists analyzing teeth from a killer whale found dead on South Uist in 2015 have concluded it was at least 65 years old, making it one of the oldest male orcas ever recorded. Researchers used the annual ringed layers in the tooth and the absence of mid-20th-century nuclear weapons testing fallout in the oldest layers to determine its age.
Key points
- A killer whale found on a South Uist shoreline in 2015 was determined to be 65 years old or older.
- Researchers studied the annual ringed layers of the orca's tooth and checked for traces of radioactive fallout from mid-20th-century nuclear weapons tests.
- The absence of nuclear fallout in the oldest tooth layers indicated the animal was born before the tests began in the mid-20th century.
- Male orcas have an average life expectancy of about 30 years, though some Scottish males like Aquarius and John Coe are thought to be over 50.
- The research was led by scientists at SUERC - Centre for the Isotope Sciences in partnership with several Scottish universities and National Museums Scotland.