tailieunhanh - bbc wildlife magazine october 2010 phần 6

Mỗi vấn đề của Bloomberg BusinessWeek tính năng trong quan điểm về thị trường tài chính, công nghiệp, xu hướng, công nghệ và những người hướng dẫn nền kinh tế. Vẽ theo Bloomberg Businessweeks phân tích sắc bén kịp thời để giúp bạn đưa ra quyết định tốt hơn về sự nghiệp của bạn, kinh doanh của bạn, và đầu tư cá nhân của bạn. | WorldMa Red crabs have evolved particularly large rounded carapaces to house their lungs - blood-rich tissue lining their gill chambers that enable them to live for long periods away from water. Christmas Island pipistrelle bat has suffered a catastrophic -and unexplained - dedine over the past two decades and is feared extinct. It was last recorded in 2009. TRUCKS TRAINS AND CRAZY ANTS But the crabs don t have it all their own way. On their treks between feeding and breeding grounds they run a gauntlet of roads servicing the island s phosphate-quarrying industry. A million crabs were crushed by cars trucks and trains each year in the 1980s the railway is no longer operational . When I arrived here in 1992 no one worried about running over crabs says National Park project officer Max Orchard. The mining trucks carried on as if they were not there - the camage was horrific. Since then Max has worked to reduce the roadkill installing fences that funnel the crabs towards purpose-built bridges and underpasses. It s wonderful to see the change in local attitudes to the migration over the time I have been on the island Max says. Now truck drivers call to tell me about high crab numbers and request road closures. Recent surveys suggest that the fatalities are down to about 300 000 crabs a year. A more serious threat comes from insects introduced from Malaysia or Singapore in the early 20th century which are wreaking havoc on not only the red crabs but also the Christmas Island also hosts the world s largest population of robber crabs which sometimes eat their smaller red cousins. structure of the island s forests. Yellow crazy ants - named for their colour and seemingly random movements when disturbed - were not a problem at first. But in the 1990s they started to form multi-queen super-colonies that occupied 25 per cent of the forest. These marauding opportunists don t bite or sting but are able to subdue their prey by spraying formic acid en masse. Their attacks have .