Saturday, October 26, 2013

10-26-13 Just How Far Can You Hear Their Sounds?

After the nighttime recording a humpback whale in Haro Strait 10-13-13
after I found out the next day 10-14-13 that my friends had heard some of those same sounds while out walking their dog,
Scott of Beam Reach sent me a question.

Here's what he said:
re: the humpback
"In AK humpback feeding sounds have broadband source levels of 162 dB (low freq grunts) through 175 (moan) and 180 (blow hole shrieks and trumpet-like blasts) to 192 dB (surface impacts). Did your friends hear all of those (and/or other) types of sounds?"
My friends replied with:
"They heard grunts and moans, and a trumpet-like (elephant-like they said). They did not hear any high pitched sounds. On the audio clip they did not hear the loud trumpet-like sound toward the end of the recording.

re: the SRKWs
That's about the intensity of SRKW calls (155 dB) and NRKW clicks (205 dB) which are often heard in air. At what range would you say one can typically hear SRKW sounds in air, Jeanne?

I haven't ever watched the whales with that question in mind, so I went back to an early morning video I took of Ks and Ls.

The video clip:
-summer of 2011
-early morning
-flat calm seas
-quiet environment
-from 15 feet above sea level
-from Lime Kiln Pt. State Park
-whales' distance: 3/4 to 1 mile

Sorry it's so shaky...
Little did I know the zooming might come in handy some day.

Sometimes their percussive sounds can be heard for over a mile, and I imagine their blows too.
I now have something else added to my questions whenever I am watching the whales.  Thanks Scott!  It will be interesting to explore this!

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