Tuna populations around the Pacific Islands could move away as ocean temperatures increase.
Climate change and shifting migration patterns are bringing rare research opportunities and new mysteries.
The military alleges the boat was travelling on a known narco-trafficking route in the Eastern Pacific.
Researchers say the footage, captured near the North-West Pacific coast, is the first recorded evidence of the two working together.
Jess Rowe and Miriam Payne told the BBC how they made the six-month journey unsupported, catching fish and growing their own vegetables.
Temperatures have surged across a large area of the north Pacific - and scientists don't know exactly why.
The Maclean brothers broke the world record for the quickest time to row unsupported from Peru to Australia.
Brothers Jamie, Ewan and Lachlan MacLean have claimed a new record for rowing non-stop and unsupported across the Pacific Ocean after almost 140 days at sea.
