Your Subwoofer Will Love Them!
Fin whales were spotted a couple of weeks before my arrival, but when I arrived, the whale watching activity had stopped for a while because of the very bad weather conditions. Once the weather cleared up a bit, we lost track of those whales, and the swell was still too high to spot them visually. Actually, the swell was too high to navigate comfortably too, but we did... What an experience! This was in autumn 2014, during my sampling session in Ireland. I used underwater microphones called hydrophones, ten meters below the surface
The whales’ signals were totally inaudible during the recording − they are very low in frequency, almost out of our hearing range − and were totally masked by the sounds of the waves around our boat (the boat engine was completely stopped, of course). So, you can imagine my surprise when I came back home thinking that the mission had failed, but then discovered those signals I didn't hear. Low frequency sounds can travel over very large distances in water. The whales I recorded were probably a few kilometers away from our embarkation!
Almost every fin whale recordings available on the Internet uses pitch transposition in order to increase the audibility of these sounds, and makes them playable through regular speakers in the middle of our hearing range. Here, I decided to remain faithful to the original recordings. This means that either big subwoofers or good headphones are required if you want to have a chance to hear something related to those whales.
During that trip, I learned that not all whales sing: only humpback whales do. Fin whales - the second largest whale after the blue whale - produces signaling tones instead of songs. That's what you'll hear here.
I am now still looking for an opportunity to record humpback whales’ songs. If anyone is able to help me, please contact me.