Orca: a two-minute wildlife lesson

Whale Week · day 5 of 7

Five facts

1. The orca is the largest dolphin. A male can reach 10 m long and weigh over 10 tonnes.
2. Orcas are nicknamed 'wolves of the sea' because, just like wolves, they hunt as a team.
3. Every orca's dorsal fin and saddle patch act like a fingerprint. Unique nicks, scratches and colour patterns let scientists identify individuals.
4. Off Argentina's Peninsula Valdes, orcas even beach themselves briefly to grab sea lions and elephant seals, then wriggle back to sea.
5. A resident pod shares a set of calls called a dialect. Individuals likely learn it through contact with pod members.

The quiz

1. What kind of animal is the orca?

• The largest dolphin (correct)
• A small whale calf
• A giant seal
• A kind of shark

A male orca can reach 10 m and over 10 t, making it the largest dolphin.

2. Why are orcas sometimes called wolves of the sea?

• They howl at night
• They hunt in groups like wolf packs (correct)
• They live on land part of the year
• They are grey

Like wolves, orcas hunt as a team.

3. What lets scientists identify individual orcas?

• The length of their tail
• Their dorsal fin and saddle patch (correct)
• Their teeth
• Their song only

Dorsal fin and saddle patch act like a fingerprint.

4. What do orcas at Peninsula Valdes do to catch sea lions?

• Dig under the sand
• Stun them with sound
• Beach temporarily to grab them (correct)
• Wait on rocks for days

They briefly beach themselves to snatch their prey, then wriggle back into the water.

5. What is the shared set of calls in a resident pod called?

• A chorus
• A signature
• A code
• A dialect (correct)

The calls shared by everyone in a resident pod are called its dialect.

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