The oceanic giants frolicked in waters to the city’s west with marine experts keeping a close eye on the action as the whales pass through on a current known as the Bonney Upwelling.

Blue whales are often sighted off the south-west coast near Cape Bridgewater but this is the first time in several years that the world’s largest animals have graced Warrnambool’s coastline.

Blue Whale Study co-director Margie Morrice was at Thunder Point yesterday to identify and document the behaviour of the visiting whales. She said six whales had been sighted off the coast with three confirmed as blue whales.

“Blue whales are seen right along the coast here, from Cape Otway to the Great Australian Bight,” Ms Morrice said.

“The unusual thing about this sighting is that they are so close to shore. We can see many blue whales off the coast near Cape Bridgewater because it’s closer to the continental shelf, but usually the only sightings near Warrnambool are by fishermen out on boats.”

Ms Morrice said the blue whales had displayed some unusual behaviour yesterday with their heads rising out of the water in search of food.

She said south-easterly breezes had swept krill closer to the shore, ensuring hungry whales got closer to the coast in search of food.

“We’re conducting an aerial survey on Thursday to determine how many are here and where they’re travelling so we should get a better idea of the situation then,” Ms Morrice said.

Department of Sustain­ability and Environment biodiversity officer Jodie Honan said tourists first spotted blue whales off the coast west of Warrnambool on Monday afternoon.

She said blue whales commonly came to Warrnambool to feed, whereas the popular southern right whales seen off Logan’s Beach visit the region to breed in August-September.