Tag Archives: Common pipistrelle

Bat girl strikes again

At last some success with bats! In fact, 3 new species (and 2 old ones) in one night!

You may have noticed that I have been struggling with identifying bats. When I go out with a bat detector without expert help I detect new species, but can’t pin down which ones. And my previous bat walk with an expert found nothing but common pipistrelles. Still, I can persevere when needed, so I went on another bat walk.

This time I headed down to Winkworth Arboretum. This National Trust site is bat heaven, including woodland and lake, and is home to seven species of bats. And they weren’t all in hiding!

About 17 people gathered just before dusk, to listen to a short talk by an expert from Surrey Bat Group. Armed with detectors we then headed into the woods.

The first species to show up were common pipistrelles, feeding over our heads, silhouetted against the still light sky. Soprano pipistrelles soon joined them. As we walked over a bridge our guide was disappointed not to see Daubenton’s bats, and I worried I wouldn’t find any new species.

We then came out of the wood, to the shore of a small lake. That’s where things really got exciting. Soprano and common pipistrelles flitted over head. Skimming the water, Daubenton’s bats scooped up insects, emitting fast clicks. Then, tuning the detector lower, we picked up serotine bats at 25khz. Finally, we picked up the deep signal of Britain’s largest (and loudest) bat, the noctule. It’s just as well we can’t hear high frequncies, as noctule bats calls can be louder than a rock concert. Imagine the complaints from neighbours!

It was amazing seeing (through occasional torch flashes) so many different bats in one place, and watching their acrobatic manoeuvres. It was particularly satisfying being able to distinguish between the species, as they had quite different call patterns and frequencies.

So, five down, 11 more to go!

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More enigmatic bats

The mad bat woman has been at it again, wondering the streets at night, waving a badly tuned radio around. This time it was a small Devon village that looked on, bemused, at my antics.

Following my recent bat walk, where only common pipistrelles came out to play, I thought I might have better luck ticking off new species from my list away from home. So I jammed my bat detector and id chart into my bag, along with a change of clothes, and jumped on a train heading west.

I was fairly confident that I would see bats, and, after dusk I was proved right, spotting my first one just a few metres from the gate of where I was staying. This time the bat detector issued a slapping, clicking sound, different to a pipistrelle. Horay, a new species to tick off my list! But what was it? My BatLib app helped to narrow the options down to three, but I really couldn’t differentiate between them, even with the help of recordings, descriptions of flight patterns and habitats. So, once again, I have seen a new species, but don’t know what it is.

A few metres round the corner I picked up some more bats. The detector made the familiar babbling, squelching sounds of common pipistrelles, but this time at a higher frequency – it was a soprano pipistrelle. Horay, a new species that I can tick off my list!
With that, I decided to call it a night. I am going to need some expert help with identifying bats. Luckily I have another bat walk with experts booked. I hope that they don’t all go into hiding like last time!

Do you have any top tips for distinguishing between bat species, using a heterodyne detector?

Bats of Nutfield Marsh

Bat detector and ID chartThose of you who’ve been following this blog for a while will know that I’ve set myself the challenge of seeing every species of British animal in the wild. One group that are proving particularly tricky at the moment are bats. There are 16 species of bat resident in the UK, 14 of which live in my home county of Surrey, so it really shouldn’t be that hard. I have a bat detector, an identification chart and an app on my phone that lets me hear recordings of different bats, as played through a heterodyne bat detector. But despite all this, I’m still not making much progress. Lots of bats sound very similar to each other, and live in similar habitats, making distinguishing them hard.

In an effort to deal with this, I thought I’d get some expert help. So Dr C and I went along to a Surrey Wildlife Trust bat walk on Nutfield Marsh, led by someone who knows their bats. It was a beautiful summers day, and the clear skies meant it didn’t get dark til late. A group of around 30 people (including lots of kids) gathered in the car park, watching flocks of ring-necked parakeets. Nutfield Marsh is a nature reserve on the site of former sand pits (not the sort kids play in). It’s now been transformed into a wonderful mix of ponds, lakes, grasslands and woods. Ideal bat habitat, and home to 5 different sorts of bats (Common and Soprano Pipistrelles, Daubenton’s, Serotine and Noctules).

A common pipistrelle bat weighs about the same as a 2p coin
A common pipistrelle bat weighs about the same as a 2p coin

 Armed with bat detectors we wandered round the reserve, and as the dusk deepened we picked up our first bats – common pipistrelles. Common pipistrelles, as their name suggests, are the most widespread and numerous of Britain’s bats. They’re also one of the smallest, weighing the same as a 2p coin.

While it’s always good to see and hear bats, I had already crossed them off my list in May, so I was really hoping to see some new species.

We headed to the largest of the lakes, and waited as the last hint of light faded, hoping to see Daubenton’s bats feeding on the insects that flitted just above the surface of the water. We did see a few more bats, but the detectors revealed them to be common pipistrelles. Eventually, the call of bed could no longer be ignored, and we headed back to the cars.

It was a little disappointing not to see some new bats, but it was very pleasant to take a stroll round Nutfield Marsh in the cool of the evening. It’s inspiring to see how an industrial landscape can be transformed into a haven for wildlife.