First spotted off Eilat in Israel in the northernmost reaches of the Gulf of Aqaba on Tuesday (29 May), it was filmed further south about 300m offshore at Taba in Egypt two days later by marine biologists working on an unrelated project.

Estimated at 20m in length, the whale, thought to be a pygmy blue, is now under observation by teams deployed by Egypt’s Ministry of Environment, which has warned that for the whale’s protection swimmers or divers should not approach it.

Blue whales live in the Indian Ocean but in summer are more likely to be found feeding in cold Antarctic waters, so the lone whale appeared to have lost its way as it sought cooler waters.

The largest creatures on the planet and a protected species, blue whales tend to travel alone or in pairs.

Large whales of any sort have only rarely been spotted in the Red Sea, which does not support their favoured food source of krill.

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