Humpback whales are known for their acrobatic displays and complex vocalizations. Their unique approach to consuming vast amounts of food reveals a fascinating adaptation perfectly suited to their aquatic environment.
No Teeth for Humpback Whales
Humpback whales do not possess teeth in their mouths. Instead, these whales have evolved a specialized filtering system known as baleen. This adaptation allows them to efficiently consume their preferred diet of small prey, such as krill and small schooling fish, which do not require chewing. The absence of teeth is a defining characteristic for humpback whales.
What is Baleen?
Baleen consists of numerous plates that hang from the upper jaw of the whale, resembling long, flexible bristles. These plates are composed of keratin, the same fibrous protein found in human fingernails and hair. Varying in color from black to yellow or white depending on the species, the outer edge of each baleen plate is smooth, while the inner edge is frayed, forming a mat of fine, hair-like fringes. This arrangement allows the baleen to function as an effective sieve, trapping small food particles while allowing water to pass through. A humpback whale can have between 270 and 400 baleen plates on each side of its upper jaw, with individual plates reaching up to 20 inches in length.
How Humpback Whales Feed
Humpback whales are filter feeders that primarily use lunge feeding to capture their prey. When a humpback whale encounters a dense school of krill or small fish, it accelerates and opens its mouth to an almost 90-degree angle, engulfing a tremendous volume of water and prey. This rapid intake is accommodated by expandable throat pleats, which are long grooves running along their underside that stretch like an accordion, allowing their mouth and throat to balloon out. Once the mouth is full, the whale begins to close its mouth partially and uses its large, muscular tongue to press the water out through the baleen plates. The fine fringes of the baleen act as a strainer, trapping the small prey inside while the excess water is expelled. After filtering, the concentrated food is swallowed. Humpbacks are also known for innovative feeding behaviors, sometimes employing techniques like bubble-net feeding, where they blow curtains of bubbles to corral prey before lunging through the concentrated group.
Toothed Whales and Baleen Whales
Whales are broadly categorized into two suborders: Mysticeti, or baleen whales, and Odontoceti, or toothed whales. Humpback whales belong to the Mysticeti group, alongside other large species like blue, fin, and right whales, all characterized by their baleen plates. In contrast, Odontoceti whales possess teeth for grasping prey. This group includes dolphins, porpoises, sperm whales, and killer whales, which use their teeth to catch fish, squid, or other marine animals.