The North Atlantic and North Pacific right whales are among the most endangered of all whales. Only around 400-500 individuals currently exist with fewer than 100 North Pacific right whales remaining. 

The North-Atlantic right whale is mostly found along the Atlantic coast of North America, where it is threatened by entanglement in fishing gear and ship collisions. Some scientists believe these whales have already been extirpated from the eastern North Atlantic and now survive only on the east coast of the U.S. and Canada. Despite seven decades of protection efforts, no population growth has been observed.

Whereas groups of North Atlantic right whales once numbered in the hundreds in feeding grounds, nowadays they usually travel alone or in groups of 2-3 (sometimes up to about 12).

As with other mammals, right whale mothers and their calves display strong attachments, with the calf keeping in close contact with its mother by swimming up on her back or butting her with its head. Sometimes the mother may roll over to hold her calf with her flippers. Mating pairs are reported not to maintain long-term bonds. 

Females breed about once every three to five years. Gestation is about one year and the single calf is nursed for nine to 12 months. Pregnant females migrate to an area off the coast of Georgia and Florida to give birth between December and March and then migrate north to their feeding grounds in the Bay of Fundy. Scientists are confident there is at least one other nursery area but have yet to discover it. Where these whales mate is also a mystery.