A fascinating video has captured the heart-pounding moment two enormous whales are recorded "mugging" a boat filled with tourists.
The video shows two gray whales splashing within mere inches of the Shearwater boat, which is the wildlife-watching vessel, which sails out of Newport Beach in the US state of California.
The vessel, which can hold up to 15 people, is operated by Newport Coastal Adventure who called it "one of the most epic gray whale encounters of all time".
In the video, the whales can be seen rolling and hopping, and suddenly became extremely interested and fascinated by the boat and the passengers.
Education manager Jessica Roame said: "The encounter lasted for over 45 minutes as the whales were rolling and spy hopping, and became extremely interested in our boat and the passengers.
"We call this behaviour 'mugging'. The term mugging means to be 'held up', so it's kind of a playful way to describe that the boat is unable to move, and is being 'held up' by a curious, friendly or playful whale."
Jessica admitted when the whales start to approach near the boat, there is very little they can do until the whales decide what to do next.
She admitted: "When whales start to approach in this way we are at their mercy - and until they decide to leave of their own accord, we can't turn the motors back on and move along, so we don't hurt or scare them.
"This could last 15 minutes or two hours, and it's a very special and amazing thing to witness."
Passengers were left awe-struck and couldn't believe their luck after witnessing such a rare occasion, with many passengers certainly getting their money's worth from the boat trip.
The encounter, Jessica said, is "very rare" which unfolded just two miles offshore.
She said: "It was incredible. The passengers were just awestruck by the friendliness of these big whales.
"We all felt extremely grateful to have such a special encounter with the whales, since it's such a rare occurrence."
Gray whales, which grow to be around 49ft long, make an annual migration between January and late May from their breeding grounds in Mexico up to Alaska.
Boats are advised to move slow when whale-spotting and to keep their distance, with gray whales often approaching boaters if the engines are switched off.
Jessica said: "Occasionally, if you are respectful, with engines off, these whales will approach boaters on their own accord like these two did."
