Cystophora

Cystophora is a monotypic genus of true seal, family Phocidae, containing the single species the hooded seal, native to the North Atlantic from Svalbard in the east to the Gulf of St. Lawrence in the west, with four distinct breeding regions and documented migratory sightings as far as Alaska and the Mediterranean. The genus name means bladder-bearer in Greek, for the inflatable nasal cavity that adult males develop around age four and use for acoustic signaling and mate attraction. Adults show strong sexual dimorphism: males average 2.6 meters and 300 to 410 kilograms, while females average about 2 meters and 145 to 300 kilograms.