Southern Right and Humpback Whales

Humpback whales from Whitecrest Great Ocean Road ResortOur Precious Whales are Back

Humpback Whale

Yes, it has already started – our visitors are beginning to appear along the pristine Victorian coast after spending their summer feeding in the Antarctic and sub-Antarctic. And at this time of the year, it is difficult to know exactly what we are seeing, whether it be the Humpback, on its way to warmer waters off the Queensland coast, or the first presence of our very own, very special Southern Right Whale.

We will not see Blue Whales because these are summer time visitors, plus they are not visible from the shore as they keep away from the coast. They feed along the Bonney Upwelling where the deep and cold Antarctic waters meet with the underwater shelf associated with the Australian southern land mass – this is their perfect summer feeding ground.

From November to May, Blues are seen anywhere out from Cape Otway going west well into South Australian waters, but remember they swim off the coast, so we will not see them close to shore.

humpback whalesThe Humpback, on the other hand, is usually a passing visitor as part of its very long migration from the Antarctic feeding grounds to an unknown breeding location off the Queensland coast. The old, the young, or those females not in the cycle for breeding may dwell on the coast and that’s where we may get lucky. A Humpback might make a longer visit like when one stopped over in Port Phillip Bay just four years ago with sightings made off Mordialloc. In the same season another was seen in Western Port Bay off Stony Point.

Humpbacks are renowned for their breaching – breaking out of the water. This is possibly a communication method, possibly a display of energy and vitality; researchers are not entirely sure.

Viewings can occur any time from April to September and it can be difficult to tell whether you are seeing a Humpy or a Righty. According to the experts, you should look for the dorsal fin and a slim and smaller body to identify a humpback. The humpback sports the more uniform dark grey body and white underbelly.

Our very own Southern Right Whales are the giants of the ocean, born with a length of around 5.5 metres and weighing 1 to 1.5 tonnes. Adult females grow to 17.5 metres and weigh 85 tonnes. Males are 2 metres shorter and 30 tonnes lighter. Rights can best be identified by their smooth back, as they lack a dorsal fin. Then look for their blazoned white patches.

These creatures live to the grand old age of around 80 years. The Southern Right is a slow gentle giant, moving at around 4kmph, and has a very well ordered social behaviour. They feed in the sub-Antarctic waters, migrating to our coastline usually in solitude, with some exceptions. Mothers, for example, will keep with their young – a dependent calf or less often a yearling offspring – depending on which part of the three year breeding cycle they are in.

The Rights actually fast once they leave the sub-Antarctic, making their visit to our coastline a special social event, with breeding being the main objective.

And when we say ‘special’, this is no exaggeration. There are only an estimated 2500 to 3000 Rights in existence, down from what was thought to have been a population of 60,000 before whaling was introduced as a commercial business, producing meat and oil which was used in lamps and other industrial applications. Whaling in our waters was banned in the mid 30’s – so the nearly 80 year time span has been a very slow and very precarious period of regeneration. In contrast, the estimated current population for Humpbacks along our east coast is around 20,000.

Last year was seen as being the best year on record for the Southern Right since monitoring began in 1985.

Their nursery areas include the well known Logan’s Beach at Warrnambool with an associated play area extending from Apollo Bay to Portland. Encounter Bay off Victor Harbor in South Australia is another breading location and then the most active, but very remote, is the strip of coast along the top of the Great Australian Bight in Western Australia. It is thought that this remote location was the one safe haven from the whalers and explains why today’s larger population is there. As a general rule, the Rights will habitually return to the same breeding grounds.

Southern Right Whale

Southern Right Whale

Rights are normally solitary creatures, but sometimes will migrate as a pair. They are slow swimmers, don’t stay in the one place for too long and do come very close to shore – perhaps as a defence mechanism using the background sound created by the crashing waves on the coastline to hide their activity from the acoustically sensitive killer whales.

And the good news – in mid July two years ago a breeding group, often three males to one female, was seen for the first time off the Marengo Reef Sanctuary located just west of the Apollo Bay township. This was part of an exceptional time for mating groups with larger numbers also seen at Logan’s beach.

Whale playgrounds extend beyond the nurseries to surrounding areas as the roaming males and ‘willing’ females look to form mating groups. Others are simply migrating and being part of the wider social network – those who are too young or old for mating, or females who are simply going through their three year mating cycle. A pregnancy takes twelve months, calving and nurturing takes at least another 12 months before the mothers will again become single and prepare for migration and the next mating season.

It is during the calving/mothering period that a female can be very protective and hostile to other whales. She can also forcibly jettison the maturing calf if it becomes dependent for too long – a self imposed discipline keeping her to a three year breeding cycle.

All of this social activity translates into more sightings along our coast with some special viewings like the young calf with its white blazons seen last year playing and breaching off Wongarra, out from the Whitecrest resort which is near Apollo Bay. In fact, the Rights can be seen all along our southern shores plus the adjoining lower reaches of our eastern and western coastal strips.

Buoyed by the best year ever in 2009, our people at the Department of Sustainability and Environment are very excited about the new restriction that increases the approach distance any powered marine vessel can have between it and a whale from 100 to 200 metres. This change reflects concern about maintaining the best possible environment for whales as ‘interference’ will seriously upset them.

And the good news continues. Researchers say that the numbers of Rights are increasing by 7% per annum over at Western Australia’s Bight. This figure is biologically close to the maximum growth rate.

Simply being in the same vicinity as these giant mammals gives us a special sense of connection with nature. And August will be the big month for viewing whale groups as the mothers will be assembled after a June/July birth, nurturing their new born calves in our shallow waters. They will stay for up to four months, departing during September and October to migrate back to the sub-Antarctic for summer feeding.

Logan’s beach nursery is seeing more new born each year. On a good day of social activity, 20 or more whales can be counted there, demonstrating how the Rights form larger groups in breeding areas for mating and other ‘play’.

Our experts are hopeful that the increased numbers seen in recent years is a tipping point with much more good news to come. Remember, viewing is best when the seas are calm, when there is little wind and there are no white crests. A blue sky is not necessary and a large swell will not deter the whales from their social activity, in fact it protects them. So, when you’re out on the Great Ocean Road make sure you take time to take a look; you may just be very well rewarded!

For further detailed information:
http://www.dse.vic.gov.au/dse/index.htm
http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=40
http://www.bluewhalestudy.org/