North Atlantic and North Pacific right whale

Right whales were named by whalers who thought they were the "right" whales to hunt because they are big, slow, and float when killed. Until the last century, humans hunted right whales commercially for oil, meat, and baleen. Despite a ban on hunting them, they are still at risk from a number of other threats. The North Atlantic right whale (Eubalaena glacialis) in particular is at risk of extinction.

Right whales are large, rotund, black whales with large heads. They are easily identified because they have no dorsal fin, a highly arched jaw, and a series of growths on their head called callosities. You can even identify individual whales through these callosities.

Where are they found?
Right whales prefer coastlines and large bays, but can spend a lot of time on the open sea. They are believed to have excellent hearing, especially at low frequencies, which is valuable in the dark ocean environment where vision is less useful.

What do they eat?
Right whales, like most great whales, are baleen whales. They strain and filter their food through baleen plates, eating mostly small crustaceans, including copepods and small shrimp-like animals called euphausiids.

How long do they live?
Right whales mate at around eight-years-old. Females are pregnant for about 13 months and give birth every three to five years. The calf spends most of its time swimming close to its mother and is carried in the mother's 'slip stream', the wake that develops as the mother swims. From tissue analysis, scientists believe that right whales live at least 50 years.

Right whales and hunting
Hunting has been the biggest factor in creating unstable right whale populations. There has been an international ban on hunting them since 1935.

Conservation concerns
Right whales are particularly susceptible to being hit and killed by ships, in part because they spend so much time on the surface of the ocean and because they migrate close to the coast, where vessel traffic is heavy. For some reason, they do not seem aware of approaching ships or the danger posed by them. Measures are being devised to reduce the risk posed to the whales by ship traffic, such as relocating shipping lanes and carrying out aerial and ship-based surveys to let ships know if there are whales in the area.

Right whales can also be harmed by habitat degradation, pollution and entanglement in fishing gear. With fewer than 350 individuals left, North Atlantic right whales are at a high risk of extinction.