Right whales are amoung the most endangered of every whale species. The population of a right whale is not exactly known as there are so few, but worldwildlife.org says, "Around 400 North Atlantic right whales remain; other species vary: 10,000-90,000". They have no dorsal fin and have callosities which are lifted bumps on their skin that has unique patterns. There are two species of right whale, southern right whale and northern right whale, but it doesn't make much of a difference.
Right whales are easy to spot because of their raised markings, but here is some advice on how to treat them:
A right whale is a type of baleen whale and eats zooplankton and copepods. You may sight it feeding in heavily populated areas of plankton.