He died at sea in 1677. However, the specific cause of his death isn't recorded.
It's important to note that the life of a whaler in the 17th century was dangerous and harsh. Common causes of death could include:
* Accidents at sea: Storms, shipwrecks, falls from the mast, and encounters with whales were all risks.
* Disease: Scurvy, dysentery, and other diseases were common on long voyages.
* Violence: Pirates and rival whaling crews could pose threats.
Without more specific historical records, we can only speculate about the exact cause of Francis Folger's death.