Illegal fishermen from the mainland are making daily raids into HK waters to harvest the spiky delicacy Hong Kong's sea urchin population is in danger of being decimated by illegal fishermen from the mainland who harvest thousands of the black, spiky delicacies a day. The fishermen venture into Hong Kong's waters almost daily, sending divers into restricted marine parks and reserves, and other locations on the east coast, to pillage the sea urchins from rocks and the sea bed because they have overfished their own supplies on the mainland. According to Gray Williams, the honorary director of the Swire Institute for Marine Science at Hong Kong University's ecology and biodiversity department, stocks along the east coast are being rapidly depleted. 'They are being overexploited, there is no doubt about that, but we think they're probably not in danger of disappearing,' he said, blaming mainlanders for fishing inside marine reserves. 'We've looked at the [sea urchin] population in the marine reserve in Shek O and different places in Hong Kong. Most of those places now have only babies left. 'This has been going on for some time,' he said, adding that the fishermen not only took adult urchins but also babies to stock farms on the mainland. Fishermen, unless caught red-handed in protected parks or reserves, usually have their boats confiscated and are deported to the mainland. Their boats are eventually returned. In some instances, they may be considered illegal immigrants and be dealt with by the Immigration Department. One marine policeman said the role of marine police had changed over the years, from chasing Vietnamese boatpeople, to tackling the pre-handover influx of illegal migrants from the mainland, and now hunting smugglers of trees and 'spiky little black things'. The boatyard at the Marine Police East Division headquarters in Sai Kung is full of seized boats. Twelve were returned to the mainland earlier this month, the acting divisional commander, Mark Steeple, said. 'We usually catch one or two boats a week, each manned by three crew members,' he said. Agriculture, Fisheries and Conservation Department senior marine parks officer Edward Wong Cheuk-kee said the fishermen regularly harvested sea urchins in restricted park and reserve areas. But their boats were usually powerful enough to get them back to mainland waters before they could be intercepted. 'They are organised and have scout boats to watch out for patrols. We are continuing to review the situation and talking to our counterparts on the mainland.' Mr Wong said an experienced diver could harvest up to 20kg of sea urchins in 10 to 15 minutes. 'We have no information about the distribution of sea urchins in Hong Kong, but if the activities are not curtailed, they will affect the ecology.' Mainland fishermen had told his staff that they had come to Hong Kong because 'they had depleted the stock in China'. He added: 'If we're not going to protect our own areas, the same will happen here.' Sea urchins are popular for their roe, known in Japanese cuisine as uni. Bradley White, of South Stream Seafoods which imports its sea urchins and roe from New Zealand and Australia, said the amount of roe that could be taken from individual urchins was 'miniscule', and that was why so many were being harvested.