Orca (Killer Whale)

IUCN

Scientific Name：Orcinus orca

Basic Information

Scientific classification

name：Orca (Killer Whale)
Scientific Name：Orcinus orca
Outline：Giant Fish
Family：Delphinidae Orcinus

Vital signs

length：Males 6–8 m; females 5–7 m (larger possible)
Weight：Males 4–6 t; females 2–4 t
lifetime：Females 60–80+ yrs; males 30–50 yrs

Feature

Apex predator; highly social; distinct ecotypes and dialects; cooperative hunting; strong cultural transmission.

Distribution and Habitat

Cosmopolitan—temperate to polar coasts, fjords, seamounts and upwelling zones; movements vary by ecotype.

Appearance

Black‑and‑white with pale saddle patch; adult males with tall triangular dorsal fin; curved fin in females/subadults.

Details

Orca (killer whale; Orcinus orca) is the largest delphinid and a cosmopolitan apex predator. Striking black‑and‑white coloration, males’ towering dorsal fin (up to ~1.8 m) and a pale saddle patch make it unmistakable. Multiple ecotypes differ in diet (fish‑eating vs. mammal‑eating), vocal “dialects,” hunting strategies and movement.

Ecology & Behaviour

Diets range from salmon/herring to seals, sea lions and even calves of baleen whales. Pods are matrilineal with cooperative hunting and cultural transmission (e.g., intentional stranding to grab seals, carousel feeding). Complex, stable repertoires of calls form group‑specific dialects.

Identification

Males 6–8 m (larger possible), females 5–7 m; males 4–6 t, females 2–4 t. Adult males have a tall, erect triangular dorsal fin, whereas females/subadults show a more curved fin. White eye patch and grey‑white saddle patch behind the fin.

Range & Habitat

Global oceans from polar to tropical, most common in temperate to high‑latitude coastal systems; also frequent over seamounts, upwellings and fjords. Ranging and seasonal movements vary by ecotype and prey.

Threats & Conservation

Prey depletion & fisheries interactions (specialist fish‑eating pods sensitive to target‑stock declines; entanglement/competition risks).
Noise & contaminants (shipping, sonar; bioaccumulating PCBs and other POPs).
Vessel strikes & disturbance in busy coastal waters and whale‑watching hotspots.

Actions: dynamic protection of key feeding/nursery areas, vessel‑speed management and quieter‑ship programs, pollutant reduction, and bycatch‑mitigation with fisheries.