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Whales
The Whales that we observe at Logans Beach are Southern Right whales [Eubalaena australis] They were called 'Right' Whales because they were the correct ones to hunt. The whales swim slowly, have an abundance of oil and were often found close to shore. They floated when dead.
They are about 17.5 metres in length, weigh Up to 80 tonnes. At birth they are about 5.5 metres in length and weigh 1000 to 1500 kg; gestation period - 11 months; weight at birth - up to 2 tons; a calf drinks about 600 litres of creamy milk a day, which is about 60% fat; a calf doubles it’s weight in first week; lifespan - 50 plus years [a guestimate]; swim speed about 4 to 5km/h meaning it takes many weeks to reach feeding grounds; whales are capable of short bursts of higher speeds; whales do not eat for the period they are here at Logans Beach; whale skeleton weighs 2.5 tons; nearly 1/3 of the oil derived from the whale comes from the skeleton; height of blow - 5m; speed of air leaving blow holes - 300km/h. They are mostly black in colour but white or mottly patches are sometimes seen. Their pectoral fins[front side flippers]are short and straight edged, their tail flukes likewise smooth with no distinctive markings. They have no dorsal fin and this feature along with a distinctive V shaped blow from two breath holes makes them easy to distinguish from other species of great whales.
A Southern Right whale is born with white markings on its head called callosities. These stay with the whale for life. They have a strongly arched jaw which is sometimes edged with callosities - see the picture of Thick Lips on the next page.
Right Whales do not have teeth, but filter feed using up to 270 plates which hang from their upper jaw. - See leaping calf next page. THEY DO NOT FEED IN AUSTRALIAN WATERS, but travel to latitudes 35 to 65 degrees S to gorge on small marine crustaceans which are abundant in the southern summer.
Today the world population estimated at about 5,000 - still considered vulnerable, but recovering slowly. We think there are about 13-15 breeding cows who raise their young at Logans Beach. They are still on the endangered species list.
Why do they migrate?
Baby whales would not survive the harsh Antarctic winter with its extreme cold and long months of darkness. Like all babies whale calves are relatively weak and the violent storms of the winery Southern Ocean are too much for them. They come into the relatively calm waters off our coast where there is little chance of being knocked about by ice flows.
Calving: No one has observed a Southern Right birth and so little is known. Cows appear at Beach Nursery without a calf and stay for several days. They then disappear and return a few days later with their calf. Presumably they have swum to deeper waters to give birth and may have met up with another female who will act as a protector for the mother.
Mating: Unlike most mammals, the bulls do not fight for the right to have access to the cows. Such huge animals would injure themselves, perhaps mortally if they displayed aggressive behavior toward each other. Fitness for fatherhood is determined by “sperm dominance” which is achieved by frequency of mating - the last to mate being the father. Bulls therefore need extremely large sex organs to assist in the process of multiple matings. Their sex organs are usually carried inside the body and therefore body size is the only guide to gender. It is very easy to mistake a sub adult with a bull. Whales displaying mating behavior have been observed at Port Fairy 20 km west of Warrnambool. In season 2009 there were several mating groups observed at Logans Beach Nursery, which was unusual. The new mothers are not ready to mate for at least another season and will drive off any amorous bulls who stray too close to their calf.
Play: Mothers have been observed playing with their young for hours at a time. The mother lies on her back. The baby launches itself onto her belly where it is held by the mother between her flippers. Wriggling off, the play is repeated over and over. Babies also drape their tales over the mother’s back and can lie like that for ages.
Socialization: We have observed over several years that most days cows come in close proximity of each other and swim around in a very small area. We can only assume that this is to socialize their calves.
Additional information regarding whales is available at the following web sites: The Whale and Dolphin Conservation Society aims to reduce and ultimately eliminate the continuing threats to whales and dolphins and their habitat. Visit www.wdcs.org.auThe Australian National Guidelines for Whale and Dolphin Watching 2005 outlines the standards that allow people to observe and interact with whales and dolphins in a way that ensures animals are not harmed. These are currently under review.