As guides go, you can't do much better than a trumpetfish. It's not a shark or a grouper or a 'cuda, not a tiptop predator, but this slender hunter has evolved into one of the reef's wiliest. Trumpets live throughout Bonaire's waters, but the most fascinating show comes from observing one that's actively working the seaward side of the reef crest – the start of the drop-off that's a short swim across calm water from any westside shoreline or resort dock. As you fin over the reef, you may not see any trumpetfish at first, but they're there, using both color and motion as camouflage. As you stare at a soft coral's long, vertical lines, you notice that one of the branches sways just a bit slower than the rest. That's the trumpetfish, close relative of the seahorse, waiting in ambush for an unsuspecting fish. If nothing comes along, the trumpet glides out from among the frilly stems and changes from the coral-like shade to a cruising color, a brown or orange. When it spots a herbivorous fish – often an algae-crunching parrotfish – the trumpet drafts along, molding its body to the shape of the parrot and changing its color to a similar hue. Small fish don't shy away when a parrot approaches to graze on living rock, so it must be a shock to them when suddenly it splits in two and opens a large, trumpetlike mouth to vacuum up one of their schoolmates.