Harbour porpoise (Phocoena phocoena) arching its back to dive just as its giant relatives do. However, these small cetaceans donÃŒt dive as deep. St. Lawrence estuary, Canada (RR)

harbour porpoise porpoise phocoena phocoena surfacing close up close ups close up close ups water one animal lone single swimming fin mammal cetacean arching back diving st lawrence estuary canada north america