Fisheries officials are considering banning dredgers which plough up sections of the seabed to harvest clams. Senior fisheries officer Joseph Sham Chun-hung said the Agriculture and Fisheries Department was weighing up whether to license or ban dredging and vacuum suction devices, used in Hong Kong waters for the first time this year. While trawlers are dredging, commercial and recreational fishermen are believed to be using hand-held instruments to 'Hoover up' the clams which inhabit the muddy seabed. Under the Fisheries Protection Ordinance, only toxic or explosive substances are prohibited for fishing. Alarms were raised in May when up to 30 trawlers dragging dredging devices attached to nets appeared in Wong Chuk Kok Hoi, close to Double Haven. The department wants the Fisheries Protection Ordinance's maximum fine of $10,000 increased to $200,000. It is also looking to outlaw any device deemed detrimental to the marine environment. 'By dredging quite deep into the mud you are damaging the habitat and its living organisms,' Mr Sham said. 'The kind of intensity we observed in May, it would be quite safe to say, was not sustainable.' Trawlers were feeding a market in China and Taiwan for the paphia undulata clam, which Mr Sham said was not usually eaten in Hong Kong. The new practice has sparked a row among the fishing community itself. Some have demanded clam dredging be outlawed but Mr Sham said the technique was legal in other countries such as China, the United States, Britain and Korea. 'We have to strike a balance between exploiting fisheries resources and doing it in a sustainable manner,' he said. Hong Kong Marine Conservation Society chairman Dr Brian Darvell said unregulated fishing was at fault and, as with the harvesting of sea urchins a few years ago, the supply would soon be exhausted. 'It has got to be stopped. It is crazy,' Dr Darvell said. 'Every living thing is going to get shredded in the process.'