I have never needed my snorkel on a dive, but I have never missed an article of gear as much as I missed that snorkel in Cocos. We cut a dive short to go to a massive baitball teeming with predators and prey--hundreds of sharks of different species, yellowfin tuna, dolphins, diving birds, etc. Truly amazing. The divemaster had us slide into the water on the fringe of this mayhem with no tanks-just masks and snorkels. I, of course, had a collapsible snorkel...somewhere. I usually clip it to my bc--nope. Under my seat on the panga? No. Pocket? No. Wherever it was supposed to be, it wasn't. So I spent the next half-hour surrounded by silky sharks eying me as if I were dessert and having to surface every minute or so to breathe. It was the best half-hour I have ever spent in the water. The only thing that could have improved it was a snorkel. So, whether you wear or not, be sure to bring it.