Orcas and Gray Whales
Feeding and Survival

Facts About Gray Whales and Orcas
Gray Whales Orcas (transient types)

This gray whale is "showing off" its
baleen plates
! Made of keratin (like our fingernails), baleen filters and traps food.

Photo: Michael Smith
Orcas have tall dorsal fins that can grow to 5 feet! The fins release extra heat that builds up as orcas swim.
An orca's streamlined body enables it to swim easily. When needed, an orca can swim up to 30 miles an hour for short spurts!

Size: 35-50 feet long
Weight: 28-40 tons

Size: 23-33 feet long
Weight:
4-9 tons

Eating Habits

  • Feed mainly in Arctic summer grounds on small bottom-dwelling animals called amphipods.
  • Get food by rolling on their sides along the sea floor and swimming slowly as they scrape mouthfuls of sediment off the sea floor.
  • Take in mouthfuls of water and sediment, then push it with their tongues through baleen to trap food and filter out water. Folds in their throats expand, letting them gulp up to a ton of food a day!

Eating Habits

  • Prey on seals, porpoises, gray whales, and other large sea mammals year-round. (Other types of orcas eat fish.)
  • Hunt together in small packs.
  • Cooperate, communicate, and use complex strategies to take down large animals and share the food.
  • Do not attack humans or other non-food creatures.

Young

  • Mothers are very protective of their young.
  • Calves have an instinct to feed. They experiment, explore, and put everything in their mouths!
  • A newborn gray whale is 15 feet long and weighs from 1500 to 2000 pounds.

Young

  • Mothers are very protective of their young.
  • Mothers teach calves to hunt.
  • A newborn orca is 7 to 8 1/2 feet long and weighs about 390 pounds.

Body Parts/Senses

  • A huge mouth has a 5-foot tongue weighing up to 3,000 pounds. The baleen (see photo) filters and traps food.
  • Can make sounds, but experts have much to learn about gray whales' use of sound.
  • Can mainly hear low-pitched sounds.
  • Have good vision, but the eyes are far apart, so they can't see what's directly in front of them.
  • Giant body helps a gray whale generate and hold heat — especially in cold northern feeding grounds. Large tails help with swimming and harming attackers.
  • Dig Deeper >>

Body Parts/Senses

  • Have 46 to 50 cone-shaped teeth. The upper and lower teeth interlock, which aids in gripping and tearing.
  • Use special sense of ecolocation (SONAR) to get a picture of the size and location of objects.
  • Can make and hear many different sounds. But when hunting, they remain quiet.
  • Have excellent vision in and out of water.
  • Streamlined body makes swimming easy. (When needed, an orca can swim up to 30 miles an hour for short spurts!)

Main Threats

  • Pollution from human-made chemicals and shipping waste.
  • Collisions with large ships.
  • Entanglement in fishing gear.
  • Industrial development (e.g., oil fields) near winter nurseries and summer feeding areas.
  • Habitat damage from development in beach areas.
  • Learn more.

Main Threats

  • Human-made chemicals (e.g., PCBs). West Coast orcas are the most contaminated sea animals in the world! Pollutants build up in their bodies because orcas are at the top of the food chain. Mothers also pass pollutants to babies through their milk
  • Entanglement in fishing gear.
  • Noise disturbance from shipping (can interfere with communication).
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