J’s and L’s between Williamson Rock and Lawson Reef, southbound around 1600, July 7. This is the most active part of the recording, with some strong echolocation clicks and whistles. The predominant noise (low-rev “clanking”) is from a tanker in the shipping lanes, about 3 miles away.
Listen here (1.4MB)
Posted in Research
Tagged echolocation, frequency response, recording, whale calls
The field season is rolling, with all three southern resident killer whale pods “in the area,” and whale watchers packing all of our favorite boats. I’ve been hanging out with these animals for five years now, and for the first time I’m trying my hand at research. Here is the full text of my research proposal. Keep in mind, this is undergraduate work…don’t expect doctoral quality stuff here. 
The quick and dirty: If the SRKWs calls are being masked by boat (or other) noise, they have three avenues to increase their ability to be heard. They could increase the duration of their calls (Foote, 2004), increase the amplitude of their calls(Scheifele, et al, 2005), or “shift” (using the term loosely) the frequency of their calls. Thomas (1999) showed that antarctic killer whales avoid competition for acoustic space by shifting the bulk of their calls to frequency bands outside of those used by leopard seals. Could SRKWs be responding the same way to boat noise? Hopefully we’ll find out.
Joe Olson at Cetacean Research Technology hooked me up with a calibrated C54XRS flat-response hydrophone that runs through a 20Hz high-pass filter to a FR-2LE field recorder (96kHz sample rate). I’ll be analyzing the calls using RAVEN, once my advisor hooks me up with a PC laptop.
All of my recordings will be made from aboard M/V Glacier Spirit and M/V Olympus of Puget Sound Express.