This spring we had a follow up survey of the water vole population on the HHP site overseen by a member of Brackenhurst college (part of Nottingham Trent University). There appears to be a rapid rise in the population of water voles in the main site ponds, which supports the evidence that the habitat is very suitable, with plentiful forage and low predation. The water vole population of each pond is probably at, or near the maximum capacity that can be sustained. Further evidence to support population rise is the presence of burrows and food remains at two new ponds within the site. However there were some unusual population changes in some of the newer ponds which have resulted in plans for a more detailed study over two breeding seasons. Brackenhurst staff feel there is much merit in carrying out the work and may further the understanding of water vole ecology.