Monday, 12 February 2018

Daubenton's on ice!

From BCT's Scottish Officer, Liz Ferrell, comes a fascinating story of winter bat behaviour:

Graham White, a nature enthusiast, had never seen a Daubenton’s bat before and certainly not during daylight hours! He therefore felt very lucky to see one (on two separate occasions) over the festive period where he lives in Coldstream, the Scottish Borders. Graham told us he had been walking along a section of the River Tweed on the 4th December. It was south facing and the bank was getting a lot of warmth - even on a very cold day. The old mill weir also meant the river was slow flowing and about a metre deep. The result was like a mirror with not even a ripple on the water. The only movement came from insects which dotted the surface. And then there it was, a Daubenton’s bat flying over the water at one o’clock in the afternoon!
 
By pure chance, on the 7th January, Graham saw another Daubenton’s. This time 1.5 miles from the River Tweed flying over Hirsel Lake along with the geese, swans and goldeneye he had been watching. The bat flew right next to Graham and for a further two minutes he watched and photographed the bat before it disappeared into the waterside trees. Graham mentions that the most astonishing thing this time around was that the lake was 95% covered in thin ice! The bat of course had found the other 5% unfrozen water (all thanks to some very clumsy geese after they had landed on the lake).
 
It led Graham to ask what exactly the bats were doing – were they drinking, actively foraging, both, or neither! In truth, it is hard to say. It was certainly a very surprising encounter with this little hunter. I think this story just goes to show that we have so much to learn about bats' activities through the winter and perhaps climate change is also going to have its effects. We all hope that these two bats were able to survive the winter.
 
Thank you Graham White for sharing your story and photos!


Have any readers seen anything similar? I'd love to hear about it!


Monday, 15 January 2018

Mysteries of the night

Mysteries of the night by Helen Hayes MP (species champion for the common pipistrelle)


Everyone finds different ways of coping with the shorter days and colder winter weather but some British wildlife have come up with enviable methods of getting through the worst of this season. As species champion for the common pipistrelle bat I have been discovering more about how this tiny creature, which weighs less than a pound coin, copes with the harshest of winters. Their tactic is to sleep, or rather hibernate, through the worst of the weather and start afresh when the warm weather returns. I am sure many people would quite like to spend winter that way!

Helen Hayes MP at the start of her bat walk
A lot of my knowledge about this tiny flying mammal comes from a bat walk I took part in last October. The bat walk was in West Norwood Cemetery where I was lucky enough to be accompanied by Jo Ferguson who is the Built Environment Officer for the Bat Conservation Trust (BCT) and Ian Boulton, who is the Environmental Compliance Officer for the London Borough of Lambeth. Both of these ecologists provided me with an array of interesting facts about these fascinating and important animals.  All 18 UK resident bat species eat insects and in winter these are just too scarce to be a reliable source of food so all of our bats spend the winter hibernating. Once the weather warms up enough they awake to restart their nightly chase of flying insects again.

The common pipistrelle, a species I am very proud to champion, is found right across the UK including in my London constituency of Dulwich and West Norwood. It is by far the most common bat species in the UK although its numbers are thought to have declined dramatically throughout the 20th century. I am happy to report that the work of the National Bat Monitoring Programme run by BCT shows that there are some promising signs of recovery in the common pipistrelle bat and some of the other 10 bat species they are able to monitor. Bats are a great indicator of the quality of our environment, so these signs of improvement should be welcomed by all of us.

Despite being the most common bat species, it remains a mystery as to where most common pipistrelle bats hibernate. This mystery is not restricted to the UK and researchers in the Netherlands were surprised to find that large numbers of pipistrelles were hibernating in the expansion gaps in the balconies of tower blocks.  Could some of Londons pipistrelles be hibernating in tall modern buildings? I am sure with the ongoing dedication of all the passionate volunteers involved in bat conservation we may eventually find out their secret but for now much about their lives remains a mystery.

On my bat walk I learned that there are steps we can all take to make cities more welcoming for bats and other wildlife. There is growing evidence that taking this approach is not just good for them but good for us too. Do take a look at the BCT website (www.bats.org.uk) to find out more about bats and how to get involved in their conservation. There are local bat groups right across the UK including the London Bat Group.

This year I will not only be looking forward to the warmer spring weather but will also be keeping an eye on the night skies so I can spot a different sign of spring, the acrobatic flights of the common pipistrelle bat.

Helen Hayes MP receiving her common pipistrelle poster from Kit Stoner (Joint CEO)

To find out more about the Species Champion Project go to: https://www.buglife.org.uk/specieschampions/champions