Orcas don’t just hunt with their eyes — they see with sound. Every echolocation click bounces off the salmon in front of them, and each species sends back its own unique echo. Why? Because every salmon has a different swim bladder shape and size — like an acoustic fingerprint. This means an orca can hear whether it’s Chinook, Sockeye, or Coho long before it sees it. They also use: • Depth (some species swim deeper) • Movement patterns • Body size & shape Put together, these clues help orcas choo