Lifeguards or Whistle Blowers?

Took the kids to the local swimming pool today. Had a bit of a lay in so missed the family session and went to the general swim session.
It's not the best pool we've ever been too but it's local and cheap. There were a four bigger boys there, probably aged about 16yr old ish. Anyway these boys had no consideration for any one else in the pool. All they were doing were chasing each other and play fighting but quite aggressively.

Anyway the reason I'm writing this is because of the lifeguards. There were two of them on duty, who as far as I could tell could not speak! They only had the capacity to blow a whistle. Every time these boys would do something they shouldn't all these voiceless lifeguards would do is blow their stupid whistle at them!
Now, is this a deterrent? I seriously think not! Was it working? No! After the first few times of trying, surely it would have made sense to pull these lads aside and have a few words. The words being, behave or you're out! Simples!

But no! They carried on with the whistle blowing. I could see that the voiceless lifeguards were getting annoyed with them, but surely common sense would prevail. Well it didn't. As I have learnt over the years common sense is something very few people have! All in all we were there for about an hour and a half and the boys left not long after us! Typical!

Whilst we were there as well part of the pool was closed as there was a lifeguard training course going on. I do hope that these trainees can speak. It also makes me wonder if they get taught how to blow a whistle.........