Stranded Whales.

I heard on the news the other day, that 22 Pilot Whales had been left high and dry on the beach Nr Fife, Scotland. There were 10 same species that were able to be guided back safely into the Sea.
I did read, some time ago that possibly underwater Sonar may be a possible cause.
Any thoughts on this?.
Another thought, why do the Japanese kill Whales for so called Scientific study?.
Surely mankind knows all it does need to know about them without having to kill them?.
Jim.
Lincoln .7