Whale Sharks at Lingaloo, Exmouth, West Australia
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Whale Shark, Rhincodon typus, is the largest fish on earth, growing to 55 feet in length. It can be found all over the world in the temperate regions around the equatorial belt, 30 degree north and 30 degree south. Many avid divers' dream is to see and swim with these gentle giants. These keen divers and snorkelers travel the world, but some still may not have seen one in years. Stop! Wait no more! The Whale Sharks of Ningaloo, Exmouth of Western Australia, are there during the months from March to May each year. Following the mass coral spawning, this species of Sharks come to Ningaloo Reef during this time. There are about 200 species of coral doing this super biological phenomena that lures these gargantuan sharks. Despite their huge size, Whale Shark filter-feeds only on plankton and small fish (which are attracted from the food source of the spawning). Thousands of tiny teeth in about 300 rows are not used as bitting tools, instead the shark draws in large quantity of water and extracts the plankton onto its meshed gill rakers, by straining the water through the 5 gills on each side. In the regular respiration time, the whale shark opens about 8-inches of its mouth. However, when it decides to feed (by drawing in water), it can open up to 2 feet or more. It is impressive when seeing them feed. The Department of Conservation and Land Management (CALM) conserves and manages the wildlife and the lands, waters and resources in Western Australia. CALM has licensed some tour operators to help their cost of management and research activities in this region, including the commercial whale shark watching. Tour operators enforce the rules and laws set up by CALM, making sure this activity is performed safely for both the people and the whale sharks. From the revenue generated from the whale shark watching, funds are distributed back to the researches, making sure the future generations can also have the opportunity to encounter the Whale Sharks of Ningaloo Reef. The number of Whale Shark population worldwide and the ones journey to Ningaloo are unknown (estimated to be about 200 per year). How big can they become and how long do they live are questions that scientists have been trying to get answers. Preliminary studies may indicate that male whale shark does not reach sexual maturity until 30 years of age, and incidentally about 30 feet in length at this age. New born whale sharks are about 21-25 inches long and are hatched out of the eggs while still inside the body of the mother. One rather interesting thing that I read from literature is that: there "was" no report of a whale shark being caught which "ranges from 3 to 11-1/2 feet in size", until a rare and unique incident in 1993 in the Sea of Cortez, Mexico. During this period, fishing boats had observed that sharks about 10 feet long were eagerly feeding at the surface (which in turn upset the local fishermen, like banging into their boats, etc.). These turned out to be juvenile whale sharks taking in rich zooplankton in this period. The eyes of the whale shark are small and locate behind the angle of the jaw, indicating those eyes are not of much use, suggesting that the shark normally stays in deep water in darkness. The shark usually feeds by detect prey and movements by the pores (ampullae of Lorenzini) on its lower jaw. Hence, possibly the newly hatched baby whale sharks head to the deep and do not return to the lightzone till later years. However, where do they go and their migration (if there really is) patterns are some other questions that researchers tempting to understand. There may be a couple of ways to watch whale shark (under the guidelines and rules set by the authority), since I have heard that different operators may have a slightly different approach. But generally the method is more or less the same. The following is the way that our operater deployed: We go to the sea at 8am and return at about 3pm. The operator utilizes its long-bedded dive boat during this Whale Shark season. A spotter plane is hired. It will then circle the area to locate the whale sharks, and radio down to the captain of our boat. The distance to and the direction of the cruising shark will be given, and we go. Upon arrival the location, one staff of the operator ("spotter") will get into the water and swim on top of the shark. It is because most of the whale sharks swim about 5-10 feet below the surface, and its dorsal does not break the surface. Hence, seeing them is rather difficult from the boat, therefore the powerful spotter (rotation with members of the team as the day goes by) is needed to be on top of the shark. Our captain would then drive his boat passing our spotter and the shark, and drop 4 people in the path of the cruising shark. Guests would normally pop themselves out of water to check the swimming direction of our swimming colleague, and then try to line up a good pass of our questing whale shark. As the shark passes, we would stop (none of us was as strong as our spotter). The captain would drop another 4 persons in front of the spotter, then pick the original 4 snorkelers up. Of course, sometimes the shark decides to go back to its abyss, and this encounter is mostly considered over. We would get another radio message from our spotter airplane, telling us where is the second shark. On and on, the process continues for the day. There are rules and regulations set up by CALM for the protection of the Whale Shark and the people: this code of conduct must be abided. No electronic underwater flash is used - may be upsetting the animals; Must keep clear of the direct head on path of the incoming shark; Must keep a distance about 10 feet on either side of the shark and 12 feet from the tail; cannot touch shark, nor using underwater scooter to following shark. Private vessels also has a set of "exclusive contact zone" guidelines to follow. It really is a breathtaking sight, when this 30-40 foot long behemoth comes within your reaching distance. Its beady eyes roll at you and ignore your presence. Resuming its own course of direction, the Whale Shark banks onto one side and gives the largest yawn - sing huge amount of water. All the white spots on its bluish body methodically have transformed into twinkling stars, seemingly floating on a flat palette. One would not know the size of the animal, for as the shark passes, it seems like a super long 'chu-chu train', running into infinity! For an animal with such beauty and grace, I have no clue why we (the Chinese particularly), the humans, devour their flesh and fins. It is such a loss to our children, if photos are the only remnants that are left of them in the future. The climate at Exmouth for this period is around 30 degree Celsius, and water temperature is about 25 degrees C. A lycra skin suit is adequate, for there will be physical swimming, which warms your body up. For people who want to go diving in the area, bring a 3-5mm wetsuit. Sea conditions vary from flat calm to cyclones. Unfortunately, each year, cyclones do come to Exmouth during the whale shark season. At times so bad that vessels and spotter planes simply cannot go to sea. Therefore, I would suggest you go at least 7 days to do Whale Shark Watching. Visibility ranges from 12 feet to 150 feet (generally about 35-60 feet). You will have to fly to Perth, then connect flight to Learmonth (near Exmouth). Your destined operator's staff will greet you at the airport. No injection needed; bring seasick pills and casual clothes, warm jacket at night. Have fun with the "largest fish"!! Stephen Wong |