The North Atlantic right whale is currently one of the rarest large whales in the world, having been drastically reduced to critically low numbers by years of exploitation (2). Its robust, somewhat rotund, body is mostly black, with a large head that measures up to one third of the total body length. Some individuals may also bear white patches on the underside, while others have a more mottled appearance. More often, the only conspicuous feature of this great whale are the irregular patches of thickened tissue, called callosites, on the head. These callosites are inhabited by many small amphipods, known as cyamids or whale lice, and form a pattern unique to each individual whale, thus providing a means of identification (2). The North Atlantic right whale lacks a dorsal fin (2), but has large, paddle-like pectoral fins used for steering (2) (5), and an enormous tail that provides propulsion with powerful vertical strokes (2) (5). The downward-curved mouth of the North Atlantic right whale contains between 200 and 270 baleen plates on each side of the upper jaw (2). These plates, each measuring around two metres long and fringed with fine hairs (2), replace teeth in Balaenidae
whales, and are central to their method of feeding (5). The North Atlantic right whale has two blowholes situated on top of its head through which it breathes, producing a distinctive, bushy, v-shaped cloud of spray when it exhales at the surface (5) (6).