Threat to bats remains (From The Oxford Times)

Threat to bats remains

7:50am Thursday 7th June 2012 in Letters

Sir – If the threat posed to the astonishing diversity of species of bats using Wolvercote Tunnel were truly lifted we could all heave a huge sigh of relief (Report, May 31).

Unfortunately, that is not the case. In 2010, Natural England rightly regarded maintaining the current speed limit of 40mph for trains through Wolvercote Tunnel was the only way to ensure the safe co-existence of this population of bats with operating train services.

In their intention to increase train speeds to 70mph through the tunnel, Deutsche Bahn — through their subsidiary Chiltern Railways — tested a novel lighting scheme to deter bats from entering or staying in the tunnel during train passes.

However, the very best result they could obtain — after increasing the number and intensity of lights — showed that 286 bats left the tunnel after the lights were switched on, while 182 either continued foraging or commuting within the tunnel or actually entered the tunnel during illumination time.

That represents, for the lighting scheme, an average 39 per cent failure rate for each train pass. That hardly represents a lifting of the threat to bats. Bats have simply not evolved the ability to consistently dodge oncoming objects at 70mph, since there is nothing in their natural world which flies at such level-flight speeds.

Yet there is a safe alternative: the trains could slow down for the tunnel in Wolvercote — just before or after stopping at the proposed Water Eaton Parkway station and just before or after slowing down to 25mph for North Oxford Junction. Of the 11 minutes saved in the proposed new journey times to-and-from Bicester, it would add no more than about 30 seconds.

Keith Dancey, Wolvercote