Shark Page 20

  A chimaera has some elasmobranch characteristics, namely, a cartilaginous skeleton, claspers and a poisonous dorsal fin spine, but it does not have dermal denticles or spiracles. Its eggs are fertilised internally and laid in large, hard eggcases on the seabed. Its teleost characteristics are an operculum (gill covering), a jaw fused to its skull, and combined anal and urogenital openings. Three chimaera species, the ghostshark, the Pacific spookfish and the elephant fish, are found in Australasian waters.

  Spotted ratfish (Hydrolagus colliei)

  The spotted ratfish reaches nearly one metre in length and has an eastern Pacific Ocean range from southern California to far north Alaska. It lives and feeds at depths of from 30 to 1000 metres, generally in rocky and muddy habitats. The spotted ratfish has a large head described as rabbit-like and big, shiny, emerald-green eyes. Its brown, slimy body tapers markedly to a long tail and is dappled with white spots. It uses its large pectoral fins like wings to ‘fly’ unhurriedly though the water, sometimes doing barrel rolls and corkscrews. The skin is smooth with no scales or denticles. Prey includes small crabs, worms, benthic fishes, and a cannabilistic tendency—all eaten with a modest set of teeth: just two in the lower jaw and two pairs of grinding plates in the upper jaw. Reproduction is unusual:

  Following courtship rituals, the female releases a spoon-shaped egg case every 10–14 days over a period of several months. Extrusion of the egg case from the female takes 18–30 hours after which the egg case hangs freely in the water, suspended from the female by a long slender extension of the egg case called the elastic capsular filament. Each egg case eventually becomes attached to the seabed or bottom sediments by the thin tendrils of the egg case. The incubation period within the egg case is approximately 12 months.105

  Elephant fish (Callorhinchus milii) (Plate 18)

  The elephant fish is the most anatomically distinctive of the chimaeras. Growing to just over a metre in length, it has a long, flexible, forward-protruding snout appendage covered in the ampullae of Lorenzini, with which it detects prey submerged beneath the seabed. It is found in temperate waters off South America, southern Africa and Australasia. When cruising in sunlit waters, its skin shines like aluminium foil. Elephant fish mate and lay their eggs in shallow, coastal waters, and this is when they are most vulnerable. They are harvested commercially in New Zealand and they are a favourite target of southern Australian anglers:

  Elephant fish take baits like pilchard, fish fillets and fresh squid very well and are best hooked by leaving the rod in the rod holder with enough drag on the clutch of the reel to pull the rod into a good working curve to set the hook. Anglers who hold their rod, or pounce on their rod and strike at the first sign of a bite, do miss a lot of fish. This is because elephants dislike having the bait pulled away from them before they have had a chance to eat it. Elephant fish respond well to berley and can sometimes be enticed into feeding frenzy. Should the tide be running—as is usually the case in the Barwon River [Victoria] estuary—the berley should be in a container right down on the bottom and consist of minced up fish, pilchards or the like.106

  7

  ‘AN INCREDIBLY BOUNTIFUL CROP’

  Shark Exploitation

  In the 90 billion acres of ocean that girdle our crowded planet, an incredibly bountiful crop is often unharvested. That crop is fish, a food rich in protein and containing—unlike some forms of protein on land—all the amino-acids essential to the human diet. Yet, while an estimated two out of every three persons on earth are not getting even a minimum protein diet, one of nature’s finest and most readily obtained sources of protein is virtually ignored. Some one billion tons of fish—about thirty times the current world catch—could be landed each year, and not from depleted fishing grounds such as the North Sea. But the technology of fishing remains for the most part on the level of primitive hunting, not on the level of modern farming. But we are awakening, at last, to the fact that more fish must be harvested to feed a famished world. In its Freedom-from-Hunger Campaign, the Food and Agricultural Organization [FAO] of the United Nations is seeking ways to catch and use more fish. And among them is the shark.1

  Harold McCormick and Tom Allen’s book Shadows in the Sea, from which the above quote was taken, was published in 1963 and has become a classic shark book. In the same year, the World Food Congress took place in Washington, and the FAO celebrated its twentieth anniversary, vowing to eliminate poverty. Nearly half a century later, and despite the technological advances sustaining the increasingly globalised world, the ‘Make Poverty History’ campaign was stark evidence of the ongoing battle to eliminate world poverty, to use those new technologies to ‘feed the world’.

  From the 1960s onwards, however, targeting the ‘incredibly bountiful crop’ in the world’s oceans as a major food source, while ignoring the consequences of overfishing already apparent in the North Sea’s Dogger Bank, led to wholescale, unchecked commercial plunder of marine life forms. Among them were the sharks. Between 1960 and 1970 the world’s commercial shark catch increased a massive 40 per cent, continued to rise steeply and peaked in 2000 at 869 544 tonnes.2 Such a massive cull would affect any class of animals, but is particularly dangerous for sharks:

  Chondrichthyans are generally considered to be K-selected species, displaying conservative life history parameters such as relatively slow growth, late age at maturity, low fecundity and low natural mortality, resulting in limited reproductive output. These characteristics place them at risk of overexploitation and population depletion, with an inability to recover from reduced population levels once depleted.3

  FAO data for 2003 rank the top 20 shark-catching countries (in descending order) as Indonesia, Taiwan, India, Spain, the United States, Pakistan, Argentina, Mexico, Malaysia, Japan, Thailand, France, Sri Lanka, the United Kingdom, New Zealand, Portugal, Iran, Nigeria, Brazil and Korea. Indonesia takes about fourteen per cent of the world total—twice as much as Taiwan. Not surprisingly, therefore, the Pacific Ocean (particularly the Western and Central Pacific) is the major source of the global catch. What is surprising is the fact that just one African country appears in the table, given the severe malnourishment afflicting parts of that continent. Financial assistance to African countries has not extended to the development of modern fishing fleets, because that would not offer multinationals a return comparable to that of oil or mineral exploitation. Although China does not appear on the above list, in terms of total fisheries catch and production—including teleosts, molluscs, crustaceans and aquaculture—China is by far the biggest global player.

  Original exploitation: a traditional method of catching a shark. The shark is enticed through a noose with baitfish and the noose is then tightened behind the pectoral fins. (From The Shark Callers, Glenys Köhnke, Yumi Press, 1974)

  Fish farming has become a major industry, offsetting to some extent the plundering of wild marine stocks, but even so, unequal protective legislation in different parts of the world is adding to pressures on wild marine stocks. For example, Australia’s fishing fleet has decreased significantly as more areas within the Australian Exclusive Economic Zone come under protection. However, there has been no decline in Australians’ demand for seafood, which means an increase in imports, including from ‘seriously depleted fisheries’.4

  An explosion in fish farming in countries such as China, Indonesia, Vietnam and Thailand has seen the clearing of the mangroves and other intertidal areas that were important shark nurseries. This affects more than the sharks; samples of seafood imported into Australia from these farms show traces of banned antibiotics in the form of antimicrobial chemicals used in their production. One potential consequence of the continued use of antibiotics is that ‘superbugs can develop and they can remain on the animal and come across to people and cause problems’.5

  Shark farming is not practised because of the animals’ slow reproductive and growth rates, high mortality rates in captivity, generally large size (the average shark across all species is about 1.5 metres) a
nd the associated difficulty of keeping commercial quantities—many thousands—in close proximity. That being said, farming a few smaller species could conceivably be trialled, owing to their relatively fast growth rates. These might include the milk shark (Rhizoprionodon acutus), gummy shark (Mustelus antarcticus) and smooth dogfish (Mustelus canis), the latter maturing within eight years at about 150 centimetres, with litters of up to twenty pups. There is another major obstacle: ‘no investor will put a huge sum of money in shark farming, only to yield limited returns a decade later’.6

  It is difficult to determine the total damage commercial fishing is inflicting upon chondrichthyans and, therefore, on the planet’s marine biota, of which they are such an intimate, critical component. Limited data are available for species-specific catch by quantity/weight. FAO reports simply list all categories—not individual species—that are caught. These lists, however, allow the tabulation of catches of species known to be at risk. Thus, in 2003 a reported 4230 tonnes of Portuguese dogfish (Centroscymnus coelolepsis) were taken, more than double the 2000 catch of a species already listed by the International Union for the Conservation of Nature (IUCN) as ‘Near Threatened’. Catch weights of the gulper shark (Centrophorus acus), listed as ‘Vulnerable’, dropped dramatically from 3081 tonnes in 1990 to just 141 tonnes in 2000. However, by 2003 this had increased more than sixfold to 930 tonnes. Does this suggest a recovery of gulper shark numbers or an ever-greater threat to them? These statistics are not reliable, however, as FAO data are ‘reported’ data and many countries either don’t report at all or do so inaccurately.

  Batoid catches have been increasing steadily, almost doubling between 1990 and 2003 (to 207 000 tonnes). Catches of the blue shark and the shortfin mako have also doubled over the same period (to 30 000 and 5800 tonnes respectively), which suggests that they have been specifically targeted.7

  As described in earlier chapters, sharks and rays employ a range of protective strategies, evolved over millions of years, including camouflage, dermal denticles, stinging spines, electricity, size, threat display, dark, deepwater habitats and safe, shallow pupping and nursery grounds. Since 1963, or thereabouts, these have counted for little. Modern commercial fish harvesting for human consumption is overwhelmingly thorough:

  In this type of trawl [beam trawl] the mouth or opening of the net is kept open by a beam which is mounted at each end on guides or skids which travel along the seabed. The trawls are adapted and made more effective by attaching tickler chains (for sand or mud) or heavy chain matting (for rough, rocky ground) depending on the type of ground being fished. These drag along the seabed in front of the net, disturbing the fish in the path of the trawl, causing them to rise from the seabed into the oncoming net . . .

  Demersal or bottom trawl is a large, usually cone-shaped net, which is towed across the seabed. The forward part of the net—the ‘wings’—is kept open laterally by otter boards or doors. Fish are herded between the boards and along the spreader wires or sweeps, into the mouth of the trawl where they swim until exhausted. They then drift back through the funnel of the net, along the extension or lengthening piece and into the cod-end, where they are retained . . .

  Drift nets are not set or fixed in any way, are in fact ‘mobile’, and they are allowed to drift with the prevailing currents. Drift nets are used on the high seas for the capture of a wide range of fish including tuna, squid and shark . . . Despite a global moratorium on large-scale drift nets (nets exceeding 2.5 kms in length), introduced in 1992, problems still exist . . .

  Purse seining [is] the general name given to the method of encircling a school of fish with a large wall of net. The net is then drawn together underneath the fish (pursed) so that they are completely surrounded. It is one of the most aggressive methods of fishing . . . Seine netting [is] a bottom fishing method and is of particular importance in the harvesting of demersal or ground fish including cod, haddock and hake and flat-fish species such as plaice and flounder. The fish are surrounded by warps (rope) laid out on the seabed with a trawl shaped net at mid-length. As the warps are hauled in, the fish are herded into the path of the net and caught. Effectiveness is increased on soft sediment by the sand or mud cloud resulting from the warps’ movement across the seabed. This method of fishing is less fuel-intensive than trawling and produces a high quality catch, as the fish are not bumped along the bottom as with trawling.

  Long-lining is one of the most fuel-efficient catching methods . . . It involves setting out a length of line, possibly as much as 50–100 km long, to which short lengths of line, or snoods, carrying baited hooks are attached at intervals. The lines may be set vertically in the water column, or horizontally along the bottom. The size of fish and the species caught is determined by hook size and the type of bait used.

  Dynamite fishing. In some countries such as the Philippines, explosives (dynamite or blast fishing) are used on coral reefs to capture fish. Blast fishing is a particularly destructive method of fishing and is prohibited in many regions. A single explosion can destroy square metres of coral in the immediate area, whilst shock waves can kill fish in a radius of 50m or more from the blast. Reefs in some parts of South East Asia have been reduced to rubble in this way . . .

  Cyanide is used by fishermen in many areas of South East Asia, the Pacific and the Indian Ocean, to stun reef fish such as grouper and Napoleon wrasse which are then exported for the live reef fish food market or aquarium trade. Although its use is prohibited the practice continues because of the demand for certain species (e.g. Napoleon wrasse) as gourmet delicacies.8

  The FAO also records official categories of shark production, including frozen (whole) sharks, frozen, chilled or fresh shark fillets, sharks dried, salted or in brine, skates frozen, chilled or fresh, shark fins dried and salted or unsalted, and shark liver oil. This basic terminology can be flavoured another way: probably more than 150 million sharks are manufactured into these products each year.9 Despite the public’s psychological aversion to sharks, and despite the ammoniac taste of many species’ flesh if it is not treated properly, as food products they are consumed in many ways. A random online search threw up the following international offerings: mako steak marsala; teriyaki shark steaks; baked shark cheesy surprise; grilled shark with fruit salsa; broiled spicy shark; roast angel shark; Goan stingray curry; Spanish tapa of fried tope shark in oregano marinade; smoked shark jerky; grilled shark ‘to die for’; London fried skate; Cape shark in essence of fennel; Chinese baked shark; grilled shark Mexicana; shark’s fin omelette.

  Taste is relative. According to a 2006 article in the Sydney Morning Herald:

  Fear of shark attack or not, Sydney, indeed NSW, has always had a hate affair with the fish, even to the extent of declining to eat it. Maybe it is one predator’s way of telling another ‘we won’t eat you, so you don’t eat us’, but the fact remains that shark always fetches the lowest prices at the Sydney Fish Market. A Bermagui commercial fisherman, Alan Broadhurst, sends his shark to Melbourne, where it fetches up to $10 a kilogram. ‘But in Sydney, I’d be lucky to get $5 a kilo. Three bucks would probably be closer,’ he said. The managing director of the Sydney Fish Markets, Grahame Turk, said the variety of shark species caught in NSW waters—often wobbegongs—were generally not as ‘tasty’ as sharks caught in the fisheries of Bass Strait and southern Australia. ‘People in NSW by and large just do not go for it. But there’s no doubt Victorians have developed a taste for shark,’ Mr Turk said. Over the years the fishing industry has tried to rebrand shark. It was once commonly called dogfish, a name enough to put off most diners. In the early part of last century shark was renamed monkfish to cash in on the ‘fish on Fridays’ Roman Catholics trade, but evoking religion still failed to attract interest. During the Depression shark became known as blue flake and then flake, which fooled Victorians but not people in NSW. One Newcastle fisherman, who did not want to be named, said there seemed to be so many Victorians living in Sydney now that any fish and chip shop owner who renamed his busi
ness ‘Flake Are Us’ would make a fortune each Friday from homesick southerners.10

  Sharks are targeted not only for their meat but also for their oil, cartilage, fins and for the aquarium trade. All shark industries also benefit from bycatch, the taking of sharks and rays in commercial fishing operations targeting other marine species. Reliable data on bycatch are limited; there is no way of knowing exactly what happens to the vast numbers of non-targeted sharks and rays hauled aboard fishing trawlers each year, but shark bycatch can be as much as 50 per cent of a commercial catch. It is estimated that some 400 000 tonnes of sharks are killed as bycatch alone each year, which is about half of the FAO-registered targeted shark catch noted at the beginning of this chapter. To put this another way, half of the sharks taken out of the ocean each year are ‘incidental’. Shark bycatch ranks among the most economically wasteful and ecologically damaging of all human exploitation practices. The sharks are either discarded (dead or wounded) or processed (wholly or partly).

  The most wasteful and barbaric bycatch practice is finning, for shark fin soup. The valuable fins are usually carved from the animal which is then thrown back into the sea, still alive, to sink and drown. Keeping the the whole animal would use up hold space and also risk contaminating the commercial catch with ammonia-tainted shark meat.

  Shark fins are reputed to impart certain benefits—vitality, longevity and power, all attributes of the animal itself—which is one reason why shark fin soup has always had its place in Asian, particularly Chinese, cuisine. As a delicacy traditionally enjoyed by emperors and the nobility it has considerable gourmet status and today features on the menus of Chinese banquets for celebrations such as weddings and New Year festivities. In this sense, as a cultural expression as much as a commodity, it could be likened to Beluga caviar or the best foie gras. It takes weeks of careful drying and soaking to separate out the bundle of thin collagen fibres which, supported by a cartilage platelet, grow in the fin. These fibres are called fin needles and their texture, tenderness and presentation in the soup bowl are important. The most sought-after fins are those of the blue shark, giant guitarfish (Rhyncholsatus djiddensis) and hammerhead sharks and they are among the costliest food products in the world, further encouraging their harvesting.