It's definitely not a good idea to swim in the ocean at dusk or dark! I live on the Gulf and we see sharks all the time. I almost stepped on a two and a half foot bull shark walking back to shore in the water in NW Florida. Scared the CRAP out of me! A second I saw it, a wave hit me and I jumped and luckily it carried me far away....to the shore! LOL! Of course, what do I do? I yell out, "Shark!" and a bunch of guys (my husband included!) started to follow it. When he finally came back, I had to ask him what the heck he was thinking to follow a SHARK. So truthfully, I trust the Jamaican waters more than I do here at home.