A rare sight greeted passengers and crew aboard dive and snorkel boat Silversonic this week with a mother and baby Sei Whale spotted.

The Sei Whales, which remain on the endangered species list, were seen south of St Crispin Reef on the boat's journey home from the reef .  

“The adult was aproximately 18 metres long and the calf 12 metres long," Shane Down, Skipper of Silversonic said. 

It appeared they were feeding and the mother was some 400 metres away while the young calf approached within 100 metres the vessel.  The young calf was swimming back and forth on the same track which indicated it was feeding and there were a number of tuna also in the area which eat similar food sources. 

The whales are known to be quiet inquisitive and are identified through the distinguishing feature of a single ridge extending from the blowholes to the tip of the upper jaw.

The Sei (pronounced “say”) Whales are among the more elusive of the large whales and are rarely seen inshore preferring the deeper oceans. They are one of the fastest whales with bursts of speed up to 55km/hr. 

Growing up to 20 metres and 30 tonnes, they are the third largest of the baleen whales, after the Blue Whale and the Fin Whale. Their body is dark grey with a paler underside and they feed on up to two tons of small schooling fish, squid and crustaceans each day. 

The Sei Whale is on the endangered species list with reports of less than 54,000 in the world. 

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