I have mentioned before that I do Daubenton Bat Surveys for the Bat Conservation Trust. We do two a year during August along a beautiful stretch of the River Test incorporating two separate beats (fishing areas). Access between the two beats is over two ancient, narrow and very wobbly single planks laid above the fiercely bubbling waters. There are no rails to these make-shift bridges, just whimsical branches that droop close-ish and provide the ephemeral illusion of something to grab on to in the event of slippage. There is also an insouciant sign declaring 'no entry' that hangs at a rakish angle across the chain at the start of the first 'bridge' which we merrily ignore as we clamber over it (having got both landowner's permission).
The nature of the surveys means that we cross these planks in the pitch black. Twice on each survey. I don't know how old they are, but I do know that they are nearing the end of their lives, judging from the way one of them dropped suddenly as M trod on it this week. He wobbled alarmingly, grabbed a flimsy branch and managed to remain upright (and dry) and I scuttled across after him on a wing and a prayer and made it to the other side safely. Just.
I'm generally rather scornful of Health and Safety, but there are times when even the briefest nod towards it would be a good idea.
It is quite an overhead doing the survey- you begin 40 mins after dark, stop at 10 marked points along the mile or so route and count the number of bat passes during 4 mins at each stop. It takes us two hours. As lovely as it is to see the bats and associated wildlife down by the river after dark, I think this will be the last year I do the surveys. There is so much else I need to have time for and I much prefer to be asleep at night these days instead of trampsing about the countryside :o) I am not very bat-like in that regard. When I was younger I was certainly a night-owl, but Old Age has crept up over the last few years and now I need my sleep!
Last night I attended a Bat Ecology course run by the Wildlife Trust and Very Interesting it was too. The chap doing the talk was very knowledgeable but Goodness could he talk! I thought you might like some of the info (in condensed form), so here are Twenty Useful Things To Know About Bats.
1. There are 17 breeding species of Bat in the UK and one immigrant who doesn't breed.
2. There are 1500 species of bat worldwide.
3. There are no bats in Antarctica.
4. Recent DNA tests have shown that Bats are more closely related to chimps than mice (as was previously thought).
5. Their eyesight is as good as human eyesight. Most see in black and white but Fruit bats see in colour.
6. They live for up to 30 years (depending on the species. Pips live 6-9 years).
7. They have suffered widespread population decline in the last 50 years years due to habitat loss and poisoning (timber treatments are particularly bad for bats and houses are now built without the cracks and crevices they need. Woods have been chopped down and hedgerows - used for navigating- removed. Hay meadows are no more (and the loss of associated insects) and wetlands have been built on).
8. Bats are important pollinators and hoover up insect pest species such a mozzies and those that can wreck havoc on plants (I use the term 'pest' lightly because basically, it gets applied to anything that people find annoying). It has been estimated that bats save the US economy over $6 billion a year by cleaning up crop-destroying insects. Pipistrelles eat 3000 midges every night. We have two Pips who live in our house. Perhaps we have them to thank for the low incidence of mosquito bites we get?
9. All UK bats and their roosts are protected by law. If you have bats in your roof and go up there to get a suitcase down you are technically infringing the law and could be prosecuted. To me that is where wildlife laws don't help themselves. Bats and humans have been living together for thousands of years- I don't believe that one person spending 5 mins in their loft is going to upset the resident sleepy bats so much that they all take fright and leave.
10. Bats are most active in the hour after sunset and again around sunrise, with some small activity to feed in the middle of the night.
11. Bats hibernate from November through to April (ish). They can and do wake on warm days to fly, drink and feed. Dehydration can be a big problem for them during hibernation. Babies are born in June.
12. Noctule bats (quite large) can fly at 40 mph. Serotines (bit smaller) fly at 28 mph.
13. You can id a bat from the frequency it calls at (with practice and a bat detector). Different species sound different- for eg Daubs rattle like a machine gun while Pips run up and down the scale. They also sound different when they catch an insect. In Daubs, this sounds a bit like a burp. You get your ear attuned to this when you go out regularly and listen to them.
14. Bats do not fly into people's faces/ hair/ rooms. This may very occasionally happen when they are babies and not used to flying (I've never had a bat fly into me once, despite being out among them more times than I can remember over many many years and having had them come extremely close to me on numerous occasions to check me out).
15. The Soprano Pipistrelle is the UKs commonest bat but it was only separated as a different species from Common Pips 20 years ago.
16. The single biggest predator of bats is cats- they take a 1/4 million bats every year (can't tell you the total UK bat population because no one knows).
17. Bats in the UK are rabies free, although some carry a European lyssavirus which is similar to rabies. This is why bat handlers use gloves when holding bats and are vaccinated against it.
18. It's estimated that there were 10 million Pipistrelles in the UK 40 years ago. Now there are thought to be 3 million.
19. Bats sleep inside small cracks in trees, between roof tiles, under branches. Anywhere that has two surfaces so they can get between them and feel safe and secure. Horseshoe bats sleep hanging upside down with their wings folded around them.
20. If you wake to find a bat in your room sleeping on the curtains it is most probably a juvenile. Leave it there (you need a licence from Natural England to handle even a dead bat). Leave the window open and it will find its way out again once darkness draws in.
21. (an extra one because I though it was Interesting). Some bats have learnt to fly from house to house setting off security lights and returning 5 mins later to hoover up the insects attracted to the light. Clever. Very clever. I have watched ours do this when the Moth Box is out- they usually hunt in the front of the house (their roost hole is by the front door, I've watched them crawl back into it before and swoop out as well) and out across the lake (fairly sure they are Sopranos who like water), but when the box is out they swap to the back garden and take turns to swoop over the light collecting whatever is there.
Here's a pic of a Serotin from last night. Sorry he's upside down. My mobile is doing strange things with photos at the moment. He was lovely. Had been injured so was unable to live Wild and Free but seemed content enough and was chattering away. He also had a good groom of his face and fur.
If you're interested, you could have a look tonight as it starts to get dark- there are Pipistrelles (Sopranos) all round the UK so in all likelihood you'll have a roost not far from you. They are less common in towns but if there's a river with a bridge over it it's worth hanging about there for an hour around dark and seeing what appears. You could see Sopranos, Common Pips, Noctules, Long-Eared Bats and Daubentons to name a few :o)
Hope all are well,