About Southern Right Whales
Southern right whales are 18 metre long, 80 tonne baleen whales that feed by filtering tiny prey, copepods and krill just several centimetres long, from huge mouthfuls of water. They have thick layers of blubber to keep them warm in the cold Southern Ocean waters where they feed in summer, and to act as a food reserve when fasting during the winter. In winter, they come to the coasts of Australia, New Zealand, Argentina, South Africa and some oceanic islands to breed. At this time they come in close, often just behind the breakers, and can be easy to watch from the shore.
One of the interesting things about southern right whales, and the thing that makes ARWPIC possible, is that the markings on their heads (callosity patterns) are unique to every individual – like a finger print. That makes it possible to track whales through time and place, and reveals some interesting things about them…
- southern right whale females have their first calf at 6 or 7 years of age, and they then have one calf every three years. They are slow breeders, which is why we know populations take a long time to recover from impacts, like the whaling of the 1800s
- female southern right whales usually come back to the very same coastal embayment to raise each calf, often the bay where they themselves were born…but occasionally, they swap calving areas. For the Australian population, the swap is usually between locations on the Australian coast, but sometimes even between Australia and New Zealand!
- after giving birth, mothers stay in the same coastal bay for several months, surviving on their thick blubber layers, and nursing their calf, allowing it time to grow and become strong enough for a migration south to feeding grounds in the Southern Ocean
- calves are weaned by the time of the return migration – it is rare to see a mother accompanied by a year old offspring on winter breeding grounds
- southern right whales migrate into the Southern Ocean in summer, and sometimes they go as far as 60 degrees south, even in amongst the pack ice
- whales without calves can travel thousands of kilometres along the Australian coast in a single winter season – for example all the way from Hobart in Tasmania to Albany in Western Australia.
There are still plenty of mysteries – How long do southern right whales live? Where are their migration paths? Where do females go in the years between calving? By pooling large amounts of photo-identification data, and making it available in combination with other research techniques, we can help find the answers.