August 7, 2009

Echolocation

Our sunset trip was amazing last night. We traveled around the south end of San Juan Island toward the Lime Kiln State Park. K-pod had been sighted near the light house. As soon as we arrived we were able to identify K-11.

We shut off our engine and put our hydrophone in the water. The next couple of minutes were astounding. K-pod was being particularly vocal. It is currently understood that orcas use echolocation for communication, navigation and hunting.

The process of echolocation is fascinating. Orcas do not have vocal cords in their larynx, but are able to create sounds by moving in air sacs by the blowhole. The orcas send out these high pitched clicking sounds through their melon (fatty area on their head); these sounds then are thought to hit objects. The sound then “echo’s back”, sends vibrations through the lower jaw. It is believed that these animals are able to determine the distance, size, speed, shape and even direction of objects. It is also thought that an orca’s clicks can be heard up to five miles away by other orcas.

It’s always a great adventure with San Juan Safaris!

Naturalist Jeannette Miller
Orca Whales and Wildlife Are Our Only Business. ©