In reply to malk:
The point I tried to make is that the shallow bits of the North Sea are a death trap for any sperm whale pod that, for whatever reason, happens to enter the area, as the animals get disoriented from ground reflections alone, cannot feed, etc.
One does therefore not need to invoke any special events if any whales that happen to enter the shallow areas of the North Sea eventually die. There is a reason that sperm whales are not normally found in these seas.
What went wrong is that the whales went east, either entering the Channel or going round Scotland. In either case, this would be nothing to do with increased military activity in the Baltic and North Sea.
This situation to me seems to be totally different from cases where mass strandings of whales, in areas where they are also normally found, coincide with military exercises, especially sub hunting.
CB