Appearance 
The Northern Rightwhale Dolphin is the most streamlined of the dolphins. Its long, slender and mostly black body, combined with the absence of a dorsal fin, make it look like a torpedo. In fact, while it is seldom mistaken for another dolphin, it is sometimes mistaken for a seal. Rightwhale Dolphins are as long or longer than Common Dolphins (ranging up to nearly 10 feet or 3 meters) but weigh slightly less; in fact, they weigh about as much as humans do (130-220 pounds, or 60-100 kilograms).