Invasive crayfish have "almost destroyed" biodiversity of Loch Ken in Galloway A LOCH has seen its biodiversity virtually wiped out by an "invasive alien species," according to an MSP. Uncontrolled expansion of American signal crayfish has "almost completely destroyed" the biodiversity of Loch Ken in Galloway, local MSP Alex Fergusson told MSPs yesterday. Holyrood is updating its biodiversity strategy against a backdrop of a global failure to meet international targets set for 2010, with a revised target to halt biodiversity loss by 2020. "One of the EU's targets is to ensure tighter controls on invasive alien species," Mr Fergusson said. We have a lot of ground to make up on this problem. I look out on to Loch Ken in Galloway from my home, a loch within which the biodiversity has been almost completely destroyed by the rapid, unchecked and uncontrolled expansion of American signal crayfish. "An ecosystem has been virtually wiped out, ironically, within the Galloway and South Ayrshire biosphere now recognised by Unesco as "a good way to demonstrate good nature conservation." This is a slightly odd way to demonstrate it. He added: "According to the Food and Agricultural Association in 2010, 60 per cent of the world's ecosystems were either degraded or unsustainably used, 75 per cent of fish stocks were over-exploited or significantly depleted, and 75 per cent of the genetic diversity of agriculture and crops had been lost worldwide in 20 years, three-quarters of the world's genetic crop diversity lost in two decades." Labour environment spokeswoman Claire Baker said: "The Scottish Wildlife Trust highlighted the importance of marine biodiversity, an area which is suffering decline in habitat and species. We all recognise the importance of the Marine Scotland Act, but also the frustration about the lack of a network of marine protected areas and the publication of a marine plan. Rural Affairs Committee convener Rob Gibson said the committee is examining responses to the Scottish Government's consultation on the 2020 Challenge for Scotland's Biodiversity. Environment Minister Paul Wheelhouse said: "In Scotland we can take pride that we have made good progress towards the UN target, significantly slowing biodiversity loss."