Just as we do not like to be disturbed in our comfort zone, whether it is day or night, it is the same in the marine world. Fish do react to people visiting their territory. Some withdraw further inside their niches on sensing the approach of a strange form. This is a reaction to the possibility of a predator on the prowl. Other fish become aggressive as a means to defend themselves and their territory. I discovered this during a night dive.
Alvin Douglas and I did this dive to close off my diving itinerary for 2012. As my dive master and buddy, Douglas helped me don my gear just beyond the breakers of Store Bay, Tobago. This is never an easy task as the huge waves tend to keep you off balance when you try to stand and put your flippers on in the darkness. You only see the white crest of the waves when they are already upon you.
The lights around the bay wavered and disappeared with the rippled surface as we sank into the deep. Darkness immediately enveloped us as the two beams of our lighting equipment became our only points of focus. There were tiny particles within the actual length of the beams as well as the occasionally appearance of jelly fish that chanced upon the light. One jelly fish seemed to do a graceful dance for us.
Our beams passed over the transition from the wave-marked, sandy sea floor to the coral-carpeted rocks of the reef.
Sea fans and sea plumes waved dramatically in the currents. Some tube sponges were really colourful with orange and yellow tinges.
Hovering over the reef, we saw that the reef was actually full of life. This turned out to be the Sunday school of the marine world, the fun-filled night life of the deep.
Those diurnal species that choose to retire early had indeed done so. I discovered that the barrel coral is an excellent place for a bedroom.
Fish actually sleep within the protective interior. During the day time, these same confines of this species of coral serve as important hiding places for small fish from large predators.
The beams of our lights highlighted colourful tube worms with spiralling crowns shaped like Christmas trees. These are known as Christmas tree worms. They withdrew their crowns into their tubes when we drew too close.
A lobster sat scratching his back against the coral. He apparently chose to ignore our presence as he continued the action. After a full two minutes, he leisurely made his way across a star coral and retreated into the privacy of an overhang.
At 30 feet deep, a large file fish came by to investigate us. The fish swam round and round. My camera followed him round and round. After some time the fish decided that enough was enough, it came directly towards the camera and lunged.
Another swimming round and I guess the fish really got tired of this game. It used the darkness outside our beams and sneaked in to charge a second time. It was more or less a harmless attack, but this behaviour signalled to us that it was time to leave this fish to pleasures that did not involve us.
There were myriads of other fish small and large, colourful and luminous that made our time spent on the reef worth every minute. There were just as many species of fish out in the night as there would have been during the daytime. Small fish nibbled on algae, larger fish prowled the reef searching for bigger chunks of food and some just slept the night away.
This night dive turned out to be another thrilling experience in our scuba life.