Predation research summary for 2004 Key achievements The GCT Mink Raft was used to steer incisive mink control on two rivers in southern England. Water vole numbers built up substantially during the absence of mink. Water voles recolonised stretches from which they had been absent while mink were present. GCT Mink Raft wins award from animal welfare organisation. Jonathan Reynolds
A water vole - the reason behind our work on mink eradication using the GCT Mink Raft. (Jonathan Reynolds)
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The invention of the GCT Mink Raft in 2002 initiated two years of intensive research on how best to manage the introduced mink for the benefit of native wildlife such as water voles. Improving mink control
The mink control projects on the River Itchen in Hampshire and the River Wylye in Wiltshire, already reported in the Trust’s Review of 2003, continued in 2004. On the Wylye, Trust research staff, Mike Short and Tom Porteus, have maintained both monitoring and trapping roles. On the Itchen we reduced our involvement to a monitoring role only, in line with available funding, relying on the river keepers to provide the low level of trapping required. In both cases, mink presence was held at near-zero levels from the start of the project to the end of July 2004, allowing water vole numbers to build rapidly from initial levels (see Figure 1). Indeed, water voles have been so numerous on the Wylye that they actually hindered the discovery and trapping of mink that appeared there in late summer. The latter appeared to be a female with young which either moved in from adjacent rivers, or perhaps were missed somewhere along the river corridor. Overall, though, we were very satisfied that the GCT Mink Raft had proved itself in practical mink control, and that we had developed a near-optimal strategy for using it in these conditions. There are several aspects of mink control that we would like to improve further, but shortage of external funding prevents us undertaking the research. Our involvement on the Wylye has now ended due to lack of funding, though the Itchen project is still being funded at a modest level by the Environment Agency, which also funds mink removal projects elsewhere in the UK. In general, there is a clear shortage of money in the UK for water vole conservation, and it is understandable that - having
Review of 2004