A female Risso dolphin was found washed up dead on Kirk Michael beach last week.
Government says the juvenile was 2.3 metres long and had no obvious signs of injuries.
The rare stranding was reported to the Department of Environment, Food and Agriculture and the Manx Wildlife Trust, before being removed from the beach.
Once the cause of death has been established, the skeleton will be preserved and presented to the Manx Museum to help people learn more about the species.
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