The Guardian Singing is what you do when you want to make a noise but haven't got anything much to say.
Animals also sing.
Whale song is a particularly good effort, especially when you consider they're doing it under water. Just because you can't sing doesn't mean you can't sing. There's just as much fun to be had belting out I Will Survive with every note wrong, because if you can't sing the right notes it's unlikely that you'll hear the right notes. Others will notice, however, and You May Not Survive. If challenged, you can always say it's the jazz version, because there are two things you can't argue with in life - jazz and hedges.