Whale identification requires careful observation of an animal’s physical features, behavior, and environment. This practice allows marine enthusiasts and researchers to distinguish between the over 90 species of whales, dolphins, and porpoises found across the world’s oceans. Making a positive identification requires a systematic approach, starting with broad classifications and narrowing down to species-specific details. This guide provides a framework for amateur observers to recognize these marine mammals in the field.
The Two Suborders: Toothed Whales and Baleen Whales
The first step in identification is placing the animal into one of the two major scientific suborders: Odontocetes (toothed whales) or Mysticetes (baleen whales). This distinction is based on the feeding structure.
Odontocetes, a diverse group including sperm whales, orcas, dolphins, and porpoises, possess teeth used for catching prey like fish and squid. They also have a single blowhole.
Mysticetes, which encompass great whales such as humpbacks, blue whales, and right whales, use long, fibrous plates made of keratin called baleen. These plates hang from the upper jaw and filter vast quantities of small prey, such as krill and copepods, from the water. Baleen whales have two blowholes, often resulting in a paired or V-shaped spout, and generally tend to be much larger than toothed whales, though the sperm whale is a notable exception.
Reading the Blow and Surface Profile
The visible spout, known as the “blow,” is often the first and most useful identification clue visible from a distance. The height, shape, and angle of this blow are unique to each species. For instance, the Blue Whale produces the tallest blow, a narrow, columnar plume reaching up to 30 feet high.
The North Atlantic Right Whale is recognized by its distinct V-shaped blow, created by its two widely spaced blowholes. The Sperm Whale has a low, bushy blow that is angled conspicuously forward and to the left due to the position of its single blowhole.
Observing the whale’s surface profile is also informative, including the shape of the back and the visibility of the dorsal fin as the animal prepares to dive. Fin whales, for example, have a tall, thin column-shaped blow and rarely raise their flukes, instead arching their backs high as they dive.
Key Anatomical Features for Species Identification
Specific anatomical features allow for finer species distinction. The dorsal fin is a primary marker, varying greatly in size, shape, and position. Orcas possess a very tall, straight dorsal fin, particularly in mature males, while species like the Right Whale and Bowhead Whale lack a dorsal fin entirely.
The tail, or fluke, is important for individual identification within a species. Humpback Whales, for example, are identified by the unique black-and-white pigmentation patterns on the underside of their flukes, revealed during a deep dive. The trailing edge of the fluke may also have distinct nicks and notches, which act like a fingerprint for researchers.
Further markers include unique colorations, such as the white patch behind the eye and the gray saddle patch near the dorsal fin of an Orca. Southern Right Whales are identifiable by callosities, which are roughened patches of skin on the head colonized by whale lice and barnacles.
Behavioral Cues and Geographic Range
Observing the animal’s actions on the surface provides behavioral cues for identification. These include the method and duration of diving, the size and structure of the group, and specialized feeding techniques. Humpback Whales, for example, are famous for acrobatic surface behaviors like breaching and bubble-net feeding, a coordinated method of corralling prey.
The dive sequence is species-specific; some, like the Fin Whale, rarely show their flukes before a dive, while others, like the Humpback, almost always do.
Knowing the geographic range of a sighting is a fundamental filter in the identification process. A whale seen in Arctic waters is unlikely to be a species restricted to tropical zones, immediately narrowing the number of possible candidates. Certain species, like Gray Whales, are known for specific migratory routes, and observing the pod size, such as the highly social pods of Orcas, provides an additional piece of the puzzle.