An early lesson for any ecology student is that there are always fewer predators than prey. There are more rabbits than foxes, more zebras than lions.
Unusually, coral reefs can buck this trend and can be home to a greater weight of large predators than small fish.
This is possible because the small fish replenish their numbers quickly, so the mass of them at any moment is much less than the mass added up over a year, and also because the bigger predators, being cold-blooded, need to eat far less than a similar-sized mammal or bird.
Sadly, we don’t see this pattern on most reefs because of fishing, which culls the large, long-lived predators and leaves small fish to dominate.
But Cuba, like Palau, is one of the places where the big fish are still present in impressive numbers.
In the Jardines, each dive-site has multiple large, friendly groupers, including characterful Nassau, mean-looking black groupers and ginormous Goliath groupers.
For me, grouper are all about faces, the personality that comes through from their large eyes and botoxed lips. And the friendlier the fish, the better we will be able to capture this character.
Thankfully the Jardines has plentiful inquisitive groupers, but to get the best encounters we still need to be as quiet as possible in the water.
The best technique is close-focus wide angle, and we should set up our strobes tight to the housing before we move in, to avoid unnecessary flapping around that will spook even friendly souls.
Then we just have to wait for that moment of peak eye contact or, if we’re really lucky, a yawn.