I'd say detecting your odds are less than a swimmer of a shark encounter, or a board rider looking like food. This has been a strange summer at the beach, in the over 55 weeks I've spent there I've never seen as many sharks as I seen in that week. I'm sure some of the splashes seen were blue fish and other fish feeding on the schools of bait fish but one thing for sure there were a few dorsal fins out of the water, not the small fin of a blue. I seen one while I was pier fishing scooting just behind the breaker line and it was no smaller than 6'. I've been a diver for over 32 yrs and over 200 hrs of bottom time in saltwater and I know a shark when I see one even though I never got to trust barracuda's while I was wreck diving, something about how they followed you around...lol. I think the warmer summer had a lot to do with the sharks this year, and I've notice over the last ten yrs a lack of dolphin at the beach.