The moment you realise you need... a bigger boat.
A kayaker off the coast of Western Australia had a terrifyingly close encounter with a great white shark on Thursday.
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Ian Watkins was enjoying a trip out when the five-metre animal circled him and nudged his boat from the side.
According to Mashable, he was forced to make a may day call to a whale watching vessel 600 metres away.
Speaking to ABC News, he said: "This wave was coming behind me and I thought 'what the heck's that', and then I looked on and there's this massive fin, and I thought 'that's a serious shark'.
"It pushed me from the left hand side and then it nudged me from the middle across the left hand side.
"I was trying to stay upright and then it circled me for a while and I got on the radio and said 'emergency, emergency, emergency'."
According to the Telegraph, he added: "He kept circling me, it went from the right under the kayak, then from the left under the kayak ...when it was coming under it was just really white it was massive and I thought 'holy ... bloody hell'.
Paul Guest was chartering a vessel when he picked up the may day call. He headed straight for him as fast as he could.
Mr Guest told ABC News: "The guy said it was a great white and believed it was about the size of his ski; I know the skis are at least 5, 5.2 metres long, so if it was that big, it was a fair-sized shark."
Mr Guest said he probably wouldn't kayak in that area and had some advice for Mr Watkin: "I told the guy maybe you should get a bigger boat."