THE ANIMAL FILES

Orca

Orcinus orca

Different orca communities can share an ocean without sharing a menu.

Orcas use sound while travelling, feeding and maintaining social contact. Across their range, populations differ in the prey they specialise on and in social organisation. Recognising that variation prevents one well-studied community from becoming a description of every orca on Earth.[1]

Follow the evidence ↓
Orca
Image: Robert Pittman · Commons · Public domain
Food
Specialisation differs among populations[1]
Sound types
Clicks, whistles and pulsed calls[1]
Daily activities
Foraging, travelling, resting and socialising[1]

A population’s menu

The species as a whole eats a wide range of animals, but particular populations or ecotypes may specialise. Fish-eating communities and mammal-eating communities should therefore not be treated as interchangeable hunters. Occasional deep dives also depend on the prey being pursued. Knowing the species name is a starting point; identifying the population adds important ecological information.[1]

An underwater sound repertoire

Orcas produce clicks, whistles and pulsed calls. Clicks are associated especially with orientation and distinguishing nearby objects, although they also occur socially. In resident groups, shared call patterns form dialects. Dialect learning through contact is considered likely; this does not mean every call has a known translation.[1]

Surface movement needs context

Breaching and tail-slapping occur alongside feeding, travel and rest. Proposed functions include play and communication, among others, so a single leap cannot automatically be assigned one intention. Social contact can also include coordinated surfacing and physical association between particular individuals, giving researchers repeated patterns to study rather than just spectacular isolated moments.[1]

A COMMON MIX-UP

Do all orcas specialise in the same prey?

No. Feeding specialisation differs among populations and ecotypes.[1]

TRY A LITTLE REASONING

Could a recording of shared call patterns help study group relationships?

Reveal the explanation

Yes. Dialects in studied resident groups provide recurring acoustic patterns that can be compared alongside observed social associations.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Orcinus orca (adapted and translated; exact revision)
  2. NCBI Taxonomy — Orcinus orca (identity and game lineage)

Last fact check:

One discovery leads to another

Common bottlenose dolphinAn echo helps find an object; a whistle helps keep contact.Tursiops truncatus ↗Harbour porpoiseA small coastal hunter follows fish through the water column.Phocoena phocoena ↗Beluga whaleA beluga can turn its head without turning its whole body.Delphinapterus leucas ↗