I’ve been spending lots of time going through sound files in the last few months. We have data from acoustic loggers in four different bays on the Kona coast of Hawai’i Island. The loggers take  30 second recordings every 4 minutes (so lots of data!).   I am scrolling through the files and looking at spectrograms like the one below. The beauty of a spectrogram is that you can “see” the sound and see sound that my ear cannot perceive. When I go through the files I mark down whether any individual day has  a dolphin vocalization in it or not and when the first vocalization occurs. These vocalizations are most likely spinner dolphins but could be any of a number of things, spotted dolphins, spinner dolphins, bottlenose dolphins…. Or humpback whales! I was surprised but I hadn’t run into a humpback whale vocalization yet… Until today!

Sometimes you’re scrolling through sound files looking for dolphin vocalizations and you find a humpback whale! Check it out!

Humpback in Honaunau January 22, 2012 (put on your headphones to hear it the best!)

With time along the bottom and frequency along the side we can see dark patches along the bottom. These are the humpback vocalizations. If you look at the spectrogram as you listen, you can follow along as it plays.