New research suggest that the songs of blue whales are becoming deeper. In in 1962, John Hildebrand found that the frequency of call was around 22Hz, below the range of our hearing, but last year had decreased to 15Hz. Hildebrand explains that frequency comes at a tradeoff with volume. He suggests the choice is conscious between a really loud song or one that will go really deep.
Why the change?
As their numbers have slowly increased after the devastation caused by whaling, they are having to communicate over smaller distances so their songs don’t need to be as loud and they can make them deeper.
Also of interest is that regional dialects in whale song exist. Those in the southern oceans tend to have a bit of twang and slower song, peppered with ya’ll, than there northern counterparts.
Of course all this discussion of Blues Whale got me thinking about one of my favorite all times bluesmen, John Lee Hooker. A little Tupelo below the fold.