Southern right whales are large marine mammals found in the Southern Hemisphere. These whales earned their common name from historical whalers, who considered them the “right” whales to hunt due to their slow swimming speed, coastal proximity, and their buoyancy after death, which made them easy to process for oil and baleen. This historical exploitation led to a significant decline in their populations, making them a focus of global conservation efforts today.
Distinctive Features and Behavior
Southern right whales are easily recognized by their massive size, dark coloration, and the absence of a dorsal fin on their broad backs. Adults can reach lengths of up to 18 meters and weigh around 80 tonnes. Their large heads can account for roughly one-quarter of their total body length.
Southern right whales have callosities, roughened patches of thickened skin found on their heads. These are not parasites, but appear white or yellowish due to colonies of tiny crustaceans, known as cyamids or whale lice, and barnacles that live on them. The pattern of these callosities is distinct to each whale, serving as a natural “fingerprint” that allows researchers to identify and track individuals throughout their lives.
Southern right whales are baleen whales, using flexible plates in their mouths to filter small prey from the water. They are primarily “skim feeders,” swimming slowly with their mouths open at or just below the surface to strain plankton, such as copepods and krill, through their baleen plates. This feeding method allows them to consume large quantities of these tiny organisms, sometimes over a ton of copepods per day.
These whales engage in various surface behaviors, showcasing their social and playful nature. Breaching involves the whale propelling a significant portion of its body out of the water before crashing back down. Lobtailing is another common behavior where they lift their large tail flukes out of the water and slap them forcefully onto the surface, creating a loud sound that may be a form of communication or a warning. Spy-hopping allows the whale to lift its head vertically out of the water, sometimes rotating to observe its surroundings above the surface. Southern right whales have also been observed “sailing,” where they use their elevated flukes to catch the wind.
Where They Live and How They Are Protected
Southern right whales are found exclusively in the Southern Hemisphere, in temperate and sub-polar waters between 20° and 65° South latitude. Their annual migration involves moving from colder, high-latitude feeding grounds in the Southern Ocean in summer to warmer, shallower coastal waters for breeding and calving in winter and spring. Key breeding areas include coastal waters off southern South America, South Africa, Australia, and New Zealand. Females often show strong fidelity to specific calving sites, returning to the same bays every two to five years to give birth.
Historically, southern right whales faced severe exploitation during the whaling era. Commercial hunting was banned in 1935, but illegal whaling continued in some areas until the 1970s. Despite this past, many populations have shown signs of recovery due to international and national protection efforts. The species is now protected by law throughout its range.
Despite their protected status and population recovery, southern right whales still face ongoing threats. Entanglement in fishing gear and collisions with vessels are significant concerns. Other challenges include habitat degradation from coastal and marine industrialization, increased ocean noise, and changes in prey availability due to climate change. Ongoing conservation efforts involve monitoring populations, protecting their migratory routes and breeding grounds, and developing strategies to mitigate human-related impacts.