Pollen Party

Back to insects again. There are so many out enjoying the sun.

These two were enjoying themselves alongside the Basingstoke canal.

The Basingstoke Canal runs for 32 miles, from Greywell Village in Hampshire to Woodham in Surrey. We parked the car in Odiham and walked towards the Greywell tunnel.

Read on if you like bats.

Message from the board by the tunnel:

The 1,230 yard tunnel was built between 1788 and 1792 as an alternative to a longer route around Greywell Hill. The tunnel has no towpath and therefore bargemen had to 'leg it' through whilst the horses (which had pulled the barges all the way from the London Docks) were unhitched and led over the hill to the western entrance. It could often take up to 6 hours to leg it through the tunnel.

The tunnel collapsed in 1932 and there were no attempts to revive it as commercial trade to Basingstoke had already ceased by the turn of the century. After the collapse of the tunnel all canal property above Hatch was auctioned off. Canoeists could still get through the tunnel until the late 1950s, but now the blockage is total and is estimated to be about 300 yards long.

Chalk springs rise from within the tunnel and these provide die canal with much of its water. Small shafts were driven from the tunnel sides into the chalk to encourage water to percolate back into the canal.

The tunnel is now of huge ecological importance, as a haven for bats. The blockage has created a cave like environment within the tunnel, a constant temperature (around 10°c) and high humidity provide excellent conditions for hibernating bats.
During the winter months it supports the second largest hibernating population of Natterer's bat in Europe. Five bat species have been recorded in hibernation within the tunnel Natterer's (Myotis nattereri), Daubenton's (Myotis daubentonii), Brandt's (Myotis brandtii), Whiskererd (Myotis mystacinus) and Brown long-eared (Plecotus auritus).

Large congregations of bats have been recorded 'swarming' at both east and west portals of the tunnel during the autumn months. This behaviour has been observed at other important bat hibernation sites and is believed to be associated with mating. It has been found that bats come to such sites from great distances (radius of 60km or more).

The genetic mixing as a result of mating between individuals from over such a large area helps keep bat populations healthy. During swarming studies the rare Bechstein's (Myotis bechsteinii) and Barbastelle (Barbastella barbastellus) bats have been recorded visiting Greywell tunnel.