More on diving off the Pearl Banks-by Rex. I. De Silva

More on diving off the Pearl Banks-by Rex. I. De Silva

More on diving off the Pearl Banks

Source:Island

(Continued from last week)

Sharks

In the nineteenth century the Government employed a “shark charmer” to protect divers during the pearl fisheries. He did this by means of incantations and other “magical” rituals. There apparently were no fatalities from shark attacks while he was on duty. This is hardly surprising as during the old pearl fisheries, divers and boats arrived from as far away as Arabia, (what is now) Pakistan, and India. Hundreds of divers and boats, and the resulting noise and turmoil, would have kept even the boldest sharks away. The chank divers and we did very well without the assistance of such a virtuoso.

Nevertheless, sharks (mora) were not rare – far from it. One or two harmless white-tip reef sharks often stayed around while we were spearfishing, possibly in the expectation of stealing our catch. In fact, we speared fish every day in order to feed the chank divers, boat crew and ourselves. Nurse sharks, which are primarily nocturnal, stayed in their caves during the day where we sometimes encountered them apparently in deep sleep. A variety of requiem sharks, including the blacktail, reef blacktip, graceful shark, pig-eye shark, a dangerous looking brute, and blacktip were seen from time to time.

One morning while I was spearfishing a largish shark swam towards me. The vertical dark stripes helped to identify it as a tiger shark (koti mora), a reputedly dangerous species. It was probably attracted to the fish I had speared which were on a stringer loosely fastened to my waist. I quickly undid the stringer, deciding to let the shark have the fish if it became aggressive. I also released the safety catch of my speargun and kept a finger on the trigger, although the weapon would probably have been poor protection at best.

The shark approached slowly to within about five metres, made a wide half-circle around me and then, seemingly alarmed, swam away. I had mixed feelings at the time; anxiety, combined with admiration at the beauty and grace of the creature. In retrospect, however, this encounter was to me the highlight of our expedition. This was the only live tiger shark I saw in Sri Lanka. Later I came across others in the Maldives, but that is another story. The chank divers told us that they often saw hammerhead sharks, but disappointingly we did not see any.

I speared a jack (parawa) on one of the deeper reefs, and as I was surfacing for air a largish grey shark seized the fish, tore off the posterior half and swam away, leaving only the head and part of the thorax on my spear. I am often asked if sharks are a danger and I invariably reply that they are usually a potential rather than actual danger, in Sri Lankan waters at least.

Most of the sharks we saw were accompanied by suckerfish. These are slim fish with a sucker apparatus on their heads by which they attach themselves to sharks, and other creatures, such as turtles and rays. The suckerfish feeds off scraps from its host’s meals and also gets transportation and possibly a degree of protection from its larger companion.

Large schools of yellowfin barracuda (jeela, silava) were common. These fish have a Jekyll and Hyde reputation. They school during the day when they are usually quite harmless but disperse at dusk to hunt individually. They can then become dangerous and several divers have been attacked at night.

Rays

We encountered many large eagle rays (vavul maduwa). They are gentle giants, which appear to fly underwater like enormous birds. Eagle rays relish chanks and other shellfish and we often came upon remains of their feasts on the seabed.

I saw my first guitar fish, a strange creature which looks like a cross between a shark and ray. It is however a true ray as the gill-slits are on the ventral surface. We also encountered a few electric rays. These are sluggish bottom-dwellers which have the ability to produce a powerful electric shock that is used to stun prey and also for self-defence. I might mention that as a schoolboy I hand-speared one of these rays and received a shock which made me lose hold of my spear and also deprived me of speech for a minute or two.

Turtles

The herbivorous green turtle (gal kasbava, mas kasbava) was common on the seagrass and seaweed beds. We also occasionally met with its relatives the hawksbill (pothu kasbava, pang kasbava) and olive ridley (mada kasbava, eramudu kasbava). One morning we saw a very large loggerhead turtle (Caretta caretta), so-named because of its large head. This is the second largest turtle species in our waters. We were probably the first humans it had seen as it swam around us in apparent curiosity.

Most interesting though was the giant leatherback turtle (dhara kasbava, vavul kasbava ) in which a thick leathery covering replaces the bony carapace of the other turtles. Leatherbacks grow to almost three metres in length and although not rare on the deeper banks, are wary and difficult to approach underwater. From the boat I watched one dive. It flipped backwards, almost somersaulting to submerge.

Some giant fish

Giant groupers (kossa, gal bola, gal kossa) were rather scarce, possibly due to a relative sparseness of large caves. Nevertheless we saw a few estuary groupers, at least one of which we estimated at around 100 kg in weight.

A single, large, one and a half metre long potato cod – actually a grouper despite its name – turned up when I shot a large golden snapper, which a white-tip reef shark tried to steal off my spear. The grouper also wanted the snapper and rammed the shark, making it retreat a short distance. The grouper then made for my fish and I had to kick at it and swim for the boat. The shark lost interest, but the grouper trailed me until I threw the snapper into the vessel.

While diving in deep water Rodney pointed out two large fish which resembled the common reef sweetlips (boraluwa), except that each probably weighed around 50 kg. These were the first giant sweetlips I had seen. The species was always rare and sightings few.

Two great jacks emerged from a crevice in a sandstone reef where I was diving. One bore the normal silvery-grey coloration of the species whereas, to my great astonishment, the other was black. As I had never before observed a black jack (no pun intended) I asked Rodney if he could account for this aberration. He replied that he too had on a few occasions come across this phenomenon, but had no ready explanation. It was many years later that a research paper on Caribbean marine fishes clarified the mystery. The black coloration is apparently the courtship (or mating) livery of male jacks of several species. The fish presumably revert to their normal coloration after sometime.

Leisure in camp

On some days we would finish diving early. Rodney and I would then explore the jungles around our camp, while Trevor who did not like jungles stayed back. We would encounter grey langurs, black-naped hare, and other denizens of the forest. After a shower of rain we often saw star tortoises grazing out in the open. One purpose of these jungle outings was to shoot a few grey partridge for the pot in order to vary our otherwise monotonous fish diet. Nights in the camp were peaceful and quiet. The silence was occasionally broken by the strains of “Oh Danny Boy”, Rodney’s favourite song played on his piano accordion, or sometimes by the rather mournful chants of the divers.

The dark unpolluted skies were an astronomer’s delight, with stars shining as they never do in the city. It was here that I saw my first fireball or bolide, a very bright, slow-moving meteor or shooting-star. This one left a glowing train, which remained visible for several minutes.

Reef off Silavatturai

One morning Rodney persuaded the captain to take us to Silavatturai reef, which he (Rodney) had visited earlier. The reef is shallow and is made up of magnificent corals interspersed with sandy patches. In most of these sandy areas we would find one or two large coralheads, around and under which were a variety of fish, including schools of silver sweetlips (boraluwa) and numbers of lobsters, including the large ornate spiny lobster (pokurissa).. That day we speared our quota of fish in less than fifteen minutes, and at night dined on lobster.

Several species of gastropod molluscs, including the large tiger cowrie (kavadiya) were common on the reef. The sandy areas harboured a variety of cone shells, including the colourful but highly venomous textile cone. This mollusc has a poisonous sting capable of killing a human. Colourful angelfish (manamalaya), butterflyfish, and moorish idols were almost everywhere, giving the reef a festive atmosphere. There were no large fish, the exception being a single great barracuda ( jeela, silava, ulava). This species, unlike its congener the yellowfin, can be dangerous by day as well as at night, although attacks are rare. If harpooned it will sometimes turn on its attacker and, being large and having a fearsome set of dagger-like teeth, is well able to cause severe injury or perhaps even death.

It was on Silavaturai reef that we encountered parrotfish in some numbers. These are often brightly coloured fish in which the teeth are fused into a parrot-like “beak”, giving the group its name. Parrotfish feed primarily on algae and corals; hence their relative abundance on this reef. The males of most species occur in two phases, viz. the initial phase (sexually mature) young males which resemble the females, and the older terminal phase males (“supermales”) which are usually larger and differ considerably from the younger males.

In the past this sometimes led to confusion, with females and young males being classified as one species and “supermales” as another. Despite the fair size of many individuals, they were spared from our spears as the flesh of most parrotfish, while edible, lacks flavour. Another interesting fact about this family is that many species of parrotfish secrete a mucous cocoon around themselves before settling down to sleep at night, which they do in a crevice or cave in the reef. The exact function of the cocoon is not known, but is suspected to be protective.

It was on Silavatturai reef that I first encountered the courtship of a pair of octopuses (buvalla) in four metres of water. They stayed at arms length and the (presumed) male gently stroked the female with one of its arms. I found this behaviour touching and almost human in its gentleness. Frank Lane in his classic work “The kingdom of the octopus” states that courtship can go on for hours or even days. The female octopus however makes the ultimate sacrifice. After laying her eggs in an underwater cave she stops feeding to guard and care for them. She uses the suckers on her arms to clean them and jets water from her siphon to keep them aerated. One of her duties is to protect the eggs from predators, including other octopuses. The mother often dies soon after her babies hatch out.

It was in deeper water on the seaward side of the reef that we were spectators to a mysterious act. Two large cuttlefish (poku dhalla) had joined together head-to-head with arms entwined. In this species a blue line runs around the body at the junction of mantle and fin. In the two individuals we watched, these lines glowed and pulsated like neon lights. They remained motionless, except for the rippling movements of their fins. Whether this was courtship, mating, or aggressive behaviour between two males I did not know. Rodney and Trevor were equally mystified. None of us had seen anything like it before. I learned subsequently that this was mating behaviour.

All too soon our ten-day expedition came to an end and we regrettably had to return to “civilization”. As we packed the vehicle and said good-bye to our new friends, I promised myself that I would return to the Pearl Banks someday. I never did.

Rodney passed away in November 1989. He is sorely missed by his many friends. Trevor now lives in retirement in Melbourne. We meet occasionally but strangely never talk about the underwater adventures we once shared.

(Concluded)

(Excerpted from ‘Jungle Journeys in Sri Lanka: experiences and encounters’ compiled by CG Uragoda)

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