Rorquals: Balaenopteridae

Rorquals normally swim at around 10 to 20 miles per hour (16 to 32 kilometers per hour). Some species, such as the fin whale can swim at speeds of 23 miles per hour (37 kilometers per hour) for short periods. Groups, or pods, are usually made up of two to five individuals, but sometimes large groups of rorquals come together where food is abundant. Generally rorquals do not dive deeper than 300 feet (91 meters) below the surface.

Even though different rorqual species live in different parts of the world, they all follow a migration pattern. This means that they spend part of the year in a warmer area and then move, often over great distances, to a cooler area for the other part of the year. Rorquals time their reproduction with this yearly cycle by giving birth in the warmer area and feeding in the cooler area. A female rorqual is pregnant for about a year, depending on the species, before she gives birth to a single calf. When the calf is born, it measures between 9 and 23 feet (2.7 and 7 meters) long. The young nurse, feed on their mother's milk, for about a year and grow rapidly. They become mature between five and fifteen years and live, on average, fifty to eighty years.