EX CR EN EW Coelacanth Latimeria chalumnae Until the late 1930s it was thought that the coelacanth had been extinct for 70 million years Closely related to the ancestors of land vertebrates and so called living fossils the coelacanths alive today are primitive deep sea bony fish The name refers to the fish’s hollow fin spines the Greek koilos means hollow and akantha means spine VU NT LC O in 1938 a fishing boat was trawling at a depth of about 240 feet 70 m off the coast of South Africa near Port Elizabeth when the crew spotted an unusual fish in the catch none of them had ever seen one like it before On returning to port they informed Marjorie Courtenay Latimer curator of the local natural history museum She could not identify it Marjorie Courtenay Latimer measured examined and photographed the fish and then had it stuffed She also wrote to James Leonard Brierly Smith an ichthyologist fish specialist in Grahamstown in South Africa enclosing a sketch DATA PANEL Breeding Livebearer gives birth to living young Up to 20 large eggs each measuring 3 5 in 9 cm in diameter and weighing 10 6 12 4 oz 300 350 g are released from ovaries into oviduct Developing embryos reach a length of at least 12 in 30 cm before birth Life span at least 11 years Related endangered species Sulawesi coelacanth VU Status IUCN CR Coelacanth Latimeria chalumnae Family Latimeriidae World population Unknown Distribution Comoro Islands Indian Ocean between Madagascar and southeastern Africa Sulawesi coelacanth Latimeria menadoensis lives only in oceans around Sulawesi Indonesia Habitat Cold waters in deep ocean at 240 ft 70 m Size Length up to 5 9 ft 1 8 m Weight 210 lb 95 kg Form Primitive fish with limblike pectoral fins Bluish base color with light pinkish white patches Diet Fish 8 The fish measured about 5 feet 1 5 m in length and was mauvish blue with iridescent silver markings Its odd looking fins were perhaps its most unusual feature The caudal tail fin had an extra portion sticking out at the end like an additional fin lobe There were also two dorsal back fins instead of one The paired fins were even more strange in that they had stems that looked like limbs with fin rays fanning out at the edges Fossil Record The rest as they say is history The fish was a coelacanth a primitive marine bony fish of the genus Latimeria Fish of the genus Coelacanthus had been found as fossils in rocks from the end of the Permian period 225 million years ago and at the end of the Jurassic period 136 million years ago The coelacanths were believed to have become extinct about 70 million years ago so the find was a rare creature a living fossil As such it provoked much public interest The modern coelacanth was larger than most fossil fish and had a powerful body Reports of other catches of coelacanths have been recorded in more recent years However none of the TANZANIA COMOROS MADAGASCAR MOZAMBIQUE catches has occurred in South Africa until the latest finds in Sodurana Bay Until the late 1990s the 200 or so finds all came from the waters around Comoros a small group of islands between southeastern Africa and Madagascar in the Indian Ocean However in September 1997 Mark
COELACANTH Erdman a scientist visiting the Indonesian island of Sulawesi saw an unusual looking fish being taken into the local market he immediately identified it as a coelacanth In 1998 a further specimen was found near Sulawesi questioning the long held belief that coelacanths inhabited a limited range in the Indian Ocean Sulawesi is separated from the Comoro Islands by more than 6,000 miles 10,000 km The Sulawesi coelacanths are similar apart from their coloration they are brown with golden flecks Analysis of genetic structures however indicated that the fish is a separate species with a population thought to be fewer than 10,000 mature adults Keeping the Past Alive Although it is not possible to gauge exactly how many coelacanths there are there is no doubt that they are very rare In recognition of its rarity CITES has listed the coelacanth under Appendix I thus making trade in the fish illegal Another protective measure involves the safe release of any specimens accidentally caught by fishermen The coelacanth favors cold waters at depths of about 240 feet 70 m A deep release kit first suggested by Raymond Walner a visitor to one of the coelacanth websites allows specimens to be lowered rapidly in a sack to a depth where the water is sufficiently cold and where the fish can release itself safely So far the method has proved to be the most effective way of returning coelacanths to the wild Coelacanths found today have changed little from their ancestors although they are larger than most fossil fish They have powerful bodies and limblike fins which they use to move themselves around on the sea bottom when they are looking for prey 9
EX EW CR EN VU NT LC Great White Shark Carcharodon carcharias The great white shark is a hunter par excellence It frequents a wide range of habitats and within its domain its success is matched only by that other major predator the orca or killer whale O the great white shark is magnificently designed Torpedo-shaped and armed with multiple rows of replaceable saw-edged triangular teeth it also has a battery of receptors that almost defy human comprehension It can sense its prey from distances of over 1 mile 1 6 km low-frequency sound waves can be picked up from this distance by the shark’s ears while low-frequency vibrations in the water are detected by its hypersensitive lateral line system a system of sensory organs that detect even the slightest DATA PANEL Diet Mainly bony fish but also cartilaginous fish including other sharks marine mammals including cetaceans whales and dolphins and pinnipeds seals and sea lions Breeding Gives birth to 5 10 live young probably more after a gestation period that could last as long as 1 year Related endangered species Whale shark Rhincodon typus VU Status IUCN VU Great white shark Carcharodon carcharias Family Lamnidae World population About 10,000 Distribution Worldwide but predominantly in warm-temperate and subtropical waters may also be found in warmer areas Only infrequently encountered in cold northern regions Habitat Wide range of habitats from surf line to offshore rarely in mid ocean Found between the surface and depths of 820 ft 250 m or more Size Unconfirmed reports refer to specimens in excess of 23 ft 7 m Confirmed data however indicates a maximum size of 18 20 ft 5 5 6 m Form Torpedo-shaped fish with saw edged triangular teeth System of sensory organs for detecting prey light sensitive membrane below retina for tracking movement in dim light 10 pressure changes and vibrations In addition to its long-distance senses the shark has an acute ability to detect weak electrical fields such as those emitted by fish and other prey The tiny pulses of electricity are picked up by the ends of ducts ampullae of Lorenzini located on the shark’s snout Such is the sensitivity of the ampullae that some sharks can locate prey such as flatfish even if it is buried in the sand Sharks can also sense blood the unmistakable signal sent out by injured prey at extremely weak dilutions In experiments to find out more about the shark’s capacity to detect weak solutions lemon sharks were shown to sense tuna remnants or juice at an incredibly weak dilution of one part juice to 25 million parts of water The shark’s ability to detect movement in dim light is aided by a membranous reflecting layer of cells located under the retina in the eye It acts as a mirror reflecting rays back through the retina reactivating the light-sensitive cells in the process and thus optimizing the eye’s ability to detect movement in even minimal levels of illumination This exceptional
sensory system combined with the other attributes possessed by sharks has ensured their survival for over 200 million years Pressure from Humans Exploitation by humans has taken its toll over the years Direct killing for the entertainment of professional anglers or to obtain shark products for the souvenir trade has caused significant decline Passive killing with great white sharks being caught in nets set out for other target species has also exerted pressure on populations as have shark nets installed to protect bathers along shark-threatened coastlines The combined effects of these and other threats have led to a significant decline in great white shark numbers The actual extent of this decline and the total number of great whites that remain in the wild are difficult to quantify There are several reasons for this including the diversity of nomadic and homing habits exhibited by the species Some specimens for The great white shark is an aggressive sea predator with a finely tuned sensory system However hunting and accidental killings by humans have taken their toll on population numbers instance tend to frequent relatively localized territories while others are known to roam over large distances Another complicating factor is that worldwide the species is relatively scarce As a result although a figure of 10,000 has been cited as a global total it can only be approximate Concerned by the decline several countries have implemented protection programs Measures range from banning all great white shark products to prohibiting activities such as fishing or underwater viewing by tourists Further action is being urged by conservation bodies who fear that the current IUCN listing as Vulnerable may be incorrect and that the great white shark may already be Endangered 11
