156901 Harbour Porpoise Phocoena phocoena Length 1.4-1.9m Our smallest cetacean. Lives in groups of 3-15 animals. Playful at surface. Adult has stout, streamlined body, blunt head and no beak. Flippers are small and oval and dorsal fin is triangular with concave trailing edge. Tailstock is thick and tail fin is broad. Upperparts are mainly dark grey while underparts are whitish. Has bluish grey patch on flanks, roughly between eye and start of dorsal fin.