RELATED:White whale in Middleton
It’s always exciting when one of Victor Harbor’s favourite whales comes back to visit us again.
A southern right whale named Buttons was identified and named in 2013 when she gave birth to her calf named Bow on the Fleurieu.
That year Buttons and Bow remained in the southern right whale nursery area of Encounter Bay with other mother-calf pairs for more than three months.
In the nursery area (Bashams and Middleton beaches) whale watchers were able to observe Buttons raising her calf as it grew stronger (and bigger) every day.
In 2017 Buttons was sighted and photographed by registered whale spotters, first at Waitpinga Cliffs on June 22 by Elizabeth Steele-Collins, and again the following day by Debbie Prestwood near Freemans Knob, Port Elliot.
Buttons has been seen a number of times since and whale spotters are now eagerly waiting to see if she has come to give birth in our waters again.
Identification of returning whales
Southern Right Whales are identified by the markings or white callosities (raised rough patches of skin) that form patterns on top of their large heads.
The number, shape and position of the callosities are unique to each individual whale in the same way that fingerprints are to humans.
This enables researchers to identify individuals and gather vital life history information about this species.
The movements of individuals are able to be tracked as well as what location and how often a female gives birth.
Calving females are known to return to their favoured ‘birth spots’ at three or four-year intervals.
Ms Steele-Collins, who is involved in citizen science work of whale identification, said the re-sightings were always exciting, but to confirm a positive match often took time.
“Long hours comparing photographs of the individual whale callosities and other features are necessary to establish whether individuals here now, have been here before,” she said.
“Several individual whales have been identified here in Encounter Bay during past years and a couple of special interest whales like Milky Way and Latte have visited several years in a row.
The two whales have also been photographed and catalogued by researchers at the Head of the Bight as part of the Curtin University Great Australian Bight Right Whale Study.”
Encounter Bay is recognized as a breeding ground where whales converge each year to breed, give birth and nurture young or interact and socialize.
Ms Steele-Collins said mothers often stayed in the bay for several months after they give birth, surviving on their thick blubber layers and nursing their calves, allowing them time to grow and become strong enough for a migration south to feeding grounds in sub-Antarctic waters.
“We need to do more to protect the area and make our waters a safer and quieter place to attract more whales and cater for their needs while they are here.”
“It’s amazing to think the whales travel thousands of kilometres to our coast each year.
“Being able to identify individuals, track them and observe their behaviour can reveal some interesting things about them and makes it even more fascinating”.
Water craft must steer clear
Claire Charlton is a marine biologist from Curtin University and lead researcher of the Great Australian Bight Right Whale Study at Head of Bight, specialising in cetacean population biology and underwater noise.
“Minimising disturbance to an area is very important, and the Commonwealth Conservation Management Plan for the southern right whale lists minimising anthropogenic disturbance (caused by humans) as a priority,” Ms Charlton said.
Boat users at this time of year are asked to slow down and be watching out for whales during the whale season.
The noise generated by boats and jet skis can be deafening to a whale that rely on sound as their means of communication and navigation.
Sound travels much faster under water and boats travelling at speed has the potential to cause the whales distress or disturb their behaviour.
Already this year there have been several incidents where boats have been either travelling too fast or have gone too close to the whales.
Some incidents are under investigation.
Unfortunately there have been times when whales have left our waters as a result of being disturbed by boats.
Boat activity could potentially discourage the whales from returning.
Even more concerning, it could be putting mother/calf pairs off from staying in our waters, or worse, a pregnant female may be forced to leave the area and not make it to other safe calving grounds like Head of Bight or Logans Beach in Victoria.
This would result in her giving birth in a less ideal location, where the calf is vulnerable to predation.
The minimal approach distance for a boat to any whale is 300 metres within the Encounter Bay Restriction Area.
This same distance also applies to a whale with a calf anywhere they may be found.
For the full list of guidelines and regulations, click here.
For latest whale sightings, click here.
The public are also encouraged to report all whale sightings to the SA Whale Centre by phoning 8551 0759 or online via the SA Whale Centre website.