Wild Tobago

Dr Anjani Ganase, marine biologist, asks us to use our sense of hearing even when exploring under the sea. The sounds of life are some of the clues that scientists can detect on healthy coral reefs.  When we snorkel and dive on coral reefs, the cues are mostly visual. We observe coral, sponges and soft corals of different shapes and sizes, and if we accidentally brush up against a fire coral we are quickly reminded what touch feels like. But have we thought about the sounds we hear from coral reefs? To our untrained ears, the sounds we hear – the cracking and the snapping – are like background radio static. This noisy discord comes from the busy underwater activity from the many reef residents. Reefs are incredibly noisy places and it may be difficult to distinguish particular noises, since some are outside the range of hearing for humans.  Coral reefs with higher coral cover tend to be noisier and have more diverse reef sounds. Turks and Caicos Islands. Photo Credit...

Anjani Ganase, marine biologist, looks into the world of coral reefs at some of the residents in these undersea cities. Down there, she says, it’s noisier than you think! When we dive along coral reefs, we glimpse moments in the lives of the fish and marine creatures bustling about on their daily routines in underwater coral cities. At first glance, movements may appear arbitrary, but as you observe for a minute or two we start to recognise the activity the fish is carrying out, whether it is foraging or simply hiding out. However, for more rare activities or seasonal movements, such as at dawn or dusk or during mating season, this would require longer, more consistent times spent looking into the secret lives of fish. Here are a few observations of some reef fish behaviours: Hunting buddies, the grouper and the moray eel Grouper ( Plectropomus pessuliferus ) and Giant Moray Eel ( Gymnothorax javanicus ) make an excellent partnership for hunting on the coral reefs. How ...