Tony Wu / Humpback whale (Megaptera novaeangliae) adult female at rest. The tubercles on the whale's head are clearly visible, as are the barnacles (Coronula diadema), whale lice (Cyamus boopis), and hairs on t...

Jack Dykinga / Humpback whale (Megaptera novaeangliae) fluke marked with barnacle attachments, CONANP protected area, Baja Sur, Sea of Cortez, Mexico. February.

David Fleetham / Humpback whale (Megaptera novaeangliae) pectoral fin with Whale barnacles (Coronula diadema) upon it. Whale at surface, Hawaii.

David Fleetham / Humpback whale (Megaptera novaeangliae) breaching with town of Lahaina in background. West Maui, Hawaii. February 2010.

Agustin Esmoris / Southern Right Whale (Eubalaena australis) surfacing, showing callosites covered with barnacles and lice, Chubut, Argentina

Doc White / Gray whale (Eschrichtius robustus) blow hole with barnacles and whale lice, Scammons Lagoon, Baja California, Mexico

Doc White / Humpback whale (Megaptera novaeangliae) with two kinds of barnacles, the long Gooseneck barnacle (Conchoderma aurtium) which lives on the Acorn barnacle (Coronula diadema) also whale lice, (Cyamus boo...

Tony Wu / Southern right whale (Eubalaena australis) inquisitive adult approaching to observe diver, note the callosity above the whales eye, which is populated by other organisms, including whale lice (Cyamus...

Tony Wu / Southern Humpback whale (Megaptera novaeangliae australis) dorsal fin detail with Acorn barnacles (Coronula diadema) and whale lice (Cyamus boopis) visible, South Africa

Mark Carwardine / Blue Whale (Balaenoptera musculus) dorsal fin with two remoras and barnacles, Gulf of California, Baja California, Mexico

Chris & Monique Fallows / Southern right whale (Eubalaena australis) feeding on the surface with barnacles on top of head, and baleen plates visible, De Hoop, South Africa, March.

Brent Stephenson / Humpback whale (Megaptera novaeangliae) surfacing with barnacles encrusted on its head, Wilhelmina Bay, Antarctic Peninsula, Antarctica, January.