Toakai Teitoi, 41, had gone on a fishing trip with his brother-in-law Lelu Falaile after being sworn in as a police officer.
Teitoi became stuck on the 15ft vessel on May 27, reports Sky News. The boat drifted into the Pacific Ocean and, although well stocked with food, there was little drink.
Falaile died from dehydration on July 4. Teitoi, who buried his brother-in-law at sea, said: "I left him there overnight and slept next to him like at a funeral."
A storm hit the day after Falaile died and Teitoi was able to fill two five-gallon containers with enough water to survive.
On September 11, Teitoi was woken by a noise, and when he looked overboard there was a six-foot shark circling the boat.
Teitoi claimed that when the shark had his attention it swam off, recalling: "He was guiding me to a fishing boat. I looked up and there was the stern of a ship and I could see crew with binoculars looking at me."
The Marshalls 203 vessel pulled Teitoi on board where they ensured he was in no physical danger before returning him to Majuro in the Marshall Islands several days later.
Following his ordeal, Teitoi said: "I'll never go by boat again. I'm taking a plane."
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