Brown diving beetle
Most small water beetles are black, so the brown diving beetle Agabus brunneus stands out.
These elusive insects have been recorded from a few New Forest heathland streams including Widden Bottom (otherwise they are restricted to west Cornwall and Dorset heathlands). Peak time is about September but in theory the beetles can be found all year round, although there are only five records in the Forest from 2001-2011. Even some specialists have failed to locate specimens year after year!
The ideal habitat is a stream surrounded by gorse and heather, with long marginal vegetation trailing into the water combined with water which is intermediate in flow between a riffle and a pool. Partial shade might be beneficial. The streams dry up at times and in these conditions, these beetles burrow deep into the gravel, making them even more difficult to locate. When there is water, the beetles occasionally sit on pebbles in the water but are more likely underneath pebbles.
Conservation status: RDB2 – Red list, vulnerable (just about holding on in Britain!)
Photo: Paul D. Brock