Shark Focus

MEMBER’S pagesArtisanal Shark Fishing in Tofu Beach, MozambiqueCarpet Shark Research Down UnderI am a PhD student studying their biologyand ecology. Based at the Universityof Queensland, Australia and I amstudying three species of carpet shark:the Brownbanded Bambooshark, andthe Spotted and Dwarf Banded (Ornate)Wobbegongs. All three of these speciesoccur locally, so the majority of myfieldwork is conducted in and aroundMoreton Bay, just off Brisbane.Wobbegongs are a benthic shark found aroundAustralia and South East Asia. There are currentlyseven described species of wobbegong and they allhave attractive camouflage spot patterns on theirback and fleshy lobes, known as ‘barbels’, aroundtheir mouth. Apparently, they get their name fromthese barbels as wobbegong means ‘bearded fish’ ina southern aboriginal dialect.Although wobbegong sharks are not activelytargeted by fisheries in Queensland they arefrequently caught as bycatch. There is a targetedfishery for them in New South Wales and this hasexperienced significant declines in catch rates overthe past decade. Spotted and Ornate Wobbegongshave both been classed by the World ConservationUnion (IUCN) as ‘Vulnerable’ in NSW and ‘NearThreatened’ throughout the rest of their range.The Brownbanded Bambooshark is a speciesof long tailed carpet shark. It has a large rangethat extends from the northern coast of Australiathrough South East Asia to the east coast of India.Throughout this range it is collected for aquaria andin Southeast Asia it is actively targeted by artisanalfisheries. Although not targeted in Australia it isfrequently taken as bycatch. Globally, BrownbandedBamboosharks are classed by the IUCN as ‘NearThreatened’Snorkelling with a wobbegongAll three species are important species forboth fisheries and the aquaria trade. Yet,despite their commercial importance, verylittle is actually known about their biology.The successful management andconservation of any species can only beimplemented once a sound knowledge ofits biology has been attained. Thereforethe aim of this research is to determine asmuch as possible about their biology andecology in the hope that this informationwill be applied to their sustainablemanagement and conservation.The main emphasis of my research ison the Brownbanded Bamboosharks, but Iam working in collaboration with Dr CharlieHuveneers, who recently completed astudy on wobbegong biology in NSW, withthe aim of filling any gaps of informationon wobbegong biology. Wobbegongsand bamboo sharks are frequentlyfound/caught together and it is interestingecologically to investigate how these twoapparently similar sharks co-exist.One of the study sites is the rock wall at Amity,North Stradbroke Island. This has been the siteof a tag and release study to determine spottedwobbegong growth rates. Each wobbegong is caughtby hand net while free diving and is subsequentlymeasured, weighed, tagged and then released. Thewobbegongs seem to remain in this area and ithas been possible to recapture many of them anddetermine their growth rates in the wild.A similar tag and release study of bamboo sharksis being conducted throughout Moreton Bay with thehelp of local fishers. As well as trying to determinegrowth rates other aspects of their biology is beinginvestigated including their diet, reproductive andfeeding behaviour, and their habitat use by a taggingand tracking study.The habitat an animal uses in a normal24hr cycle is often referred to as its homerange. Information regarding an animal’shome range is particularly important forthe creation of effective protection zones.To date two successful tracks havebeen conducted and provisional resultsindicate that bamboo sharks have smallhome ranges and feed on the incominghigh tide in the mangroves.Joanna SteadJo releasing a taggedcarpetshark.Fundraising for the Shark TrustAs we are going to press, long time sharkenthusiast Kosh Kelly intends to cycle fromWhitehaven, North Yorkshire to SunderlandTyne and Wear – a journey of around 100miles – in just 24 hours!Using the C2C cycle route Kosh will betaking on the challenge on the 9th Novemberand donating all of his sponsorship moneyto the Shark Trust.Asked about this epic test Kosh notes that“I’ve been training for this ride since March2007, but I don’t think any physical trainingwill help with the mental side of riding fortwenty four hours”.Our thoughts are with you Kosh and wewish you every success. If anyone wouldlike to sponsor Kosh in his challenge pleaseemail enquiries@sharktrust.org and wewill gladly pass on your details.Beside the Indian Ocean Mozambique is host toapproximately 114 species of elasmobranch fishes.I have witnessed the extirpation of four of thesespecies due to the small fleet of artisan fishermenbased nearby. The artisanal sector is widespreadalong the length of the Mozambique coastline, withan estimated 15,000 boats operating throughout.These boats provide employment for around 58,000people, but the impact on the local shark populationis devastating.There are four active shark fishers who, instead ofutilizing boats, actually swim out from the headlandsto set longlines with approximately 20 hooks to beretrieved the following day.Several elasmobranch species are caught fromTofo Beach including mantas, devil rays, whiprays,stingrays, white spotted eagle rays and zebrasharks which are targeted mainly by spear-fishers.Line fishers have been seen to land guitarfish,hammerheads, tiger and various other carcharhinidsharks during normal fishing activities, indeed severallarge ray and shark species are caught each week.Local populations of white-spotted guitarfish andbow-mouth guitarfish have been reduced to very lowlevels.I’m at Tofo Beach, Inhambane province, Mozambique,to my left is a female blacktip shark, pregnant with two pups,beside her is a juvenile tiger shark under a metre in length.In normal circumstances this would be a joyous occasion with two such beautifulanimals in close proximity. However, these sharks are dead, the fishermen who havecaught them are removing their fins to sell and the two pups are cast aside.Although shark meat is utilized, sharks are oftentargeted for their fins which are sold directly to buyersin the Mozambique capital of Maputo. There is onemain fin buyer in Inhambane. According to one spearfisher,sharks and guitarfish are target species dueto their relative large size, fins are apparently beingon-sold to Chinese buyers in Maputo.In Mozambique, catch restrictions are in place, two“tubaroes” per fisher per day is allowed with theexception of “Tubarao branco”, the white shark,the only protected shark in Mozambique (1). Thelegislation seems encouraging on paperwork, but ashark is a shark to the local fisherman on his boat,exact species identification or conservation status isirrelevant.Representatives from Eyes On The Horizon (EOTH)and local government officials joined forces toinvestigate the illegal fisheries operating from TofoBeach. This operation confiscated eight illegal longlinesrigged for sharks. Given that the large hooks,swivels and steel traces are difficult to source inMozambique, it appears likely that fishermen arebeing supplied from non-local sources.Drew Corma(1) “Colectanea de Legislacao do Ambiente” (2ndedition) Lei de Pescas:Anexo 2:page, 371.8 Send in your stories to enquiries@ www.sharktrust.org Shark Focus 30 Shark Focus 30 Send in your stories to enquiries@ www.sharktrust.org 9