Orcinus

Orcinus is a genus of cetaceans in the family Delphinidae. The only living member is Orcinus orca, commonly known as the killer whale or orca. The genus also includes several extinct species known from fossil remains. Orcinus orca is a large, highly social predator reaching 5–9 meters in length, with a distinctive black-and-white coloration and a tall dorsal fin in males. They inhabit oceans worldwide, from Arctic seas to tropical regions, favoring cold, productive coastal waters but also found offshore. They form stable social groups called pods, often matrilineal, and use complex vocalizations to communicate and coordinate hunting. Diet is highly varied; some populations specialize in marine mammals like seals, while others hunt fish or squid. They are apex predators, capable of strategic hunting and cooperative social behavior.

Reproduction is slow, with sexual maturity around 10–15 years, and gestation about 17 months. Calves stay with their mothers for several years. Orcinus orca exhibits notable ecological and behavioral diversity, with recognized ecotypes differing in prey, habitat, and vocalizations.

Threats include chemical pollution (notably persistent organic pollutants), prey depletion due to overfishing, bycatch, habitat disturbance, and the effects of climate change. Because threats and population dynamics vary by region, conservation status is assessed per population by regional authorities and the IUCN.