TEK-ING THE TEMPERATURE

RASDHOO MADIVARU is one of the Maldives’ most famous dive sites. Why? For its hammerheads, and for many divers, seeing these extraordinary sharks is their number one priority. I have guided countless divers at Rasdhoo Madivaru, and sometimes we have been lucky, but many times we weren’t, and not seeing them is always hugely disappointing.

Ever since I was a child, I have been interested in marine life, so I started to wonder about the reasons why sometimes the sharks could be found at Rasdhoo Madivaru, and sometimes they could not. I spent long periods of time in the area, diving to see these sharks. I dived the site many times, observing Nature, and comparing the conditions on each different dive. One thing I noticed was consistent in the shark sightings was the temperature; whenever I hit the thermocline, with temperatures between 28 degrees and 25 degrees Celsius, I saw several hammerheads, no matter the depth – from as little as 15 down to 40 metres.

I suggested my theory of seeing the hammerhead sharks whenever I hit the cold thermoclines to the scientists working for IUCN Maldives and they said that it might just be right. Since I am a tek diver, capable of doing deep dives, I suggested that I could place some temperature loggers (see box) in the Madivaru Channel. We placed five loggers from five metres to a depth of 60 metres.

I was the only one who was able to place the deepest logger at 60 metres,

Tek diving gives us access to rare and remote places, places not only inhabited by majestic hammerhead sharks, but that could also yield vital scientific data