Bat Hibernation Survey – South Lancashire Bat Group

All week the weather forecasts had ended with a comment about a wet and windy Sunday. Wet and windy: Two words that you don’t want to hear associated with a day you plan to spend outside or in a cave.

This time last year it was cold and dry and still. The survey then had been physically challenging, heaving yourself in and out and around unusually shaped and composed environments. My arms and legs had got tired in new ways. I hadn’t taken quite enough food to stay at the optimum level of cheerful for the whole day. But it had been great and I had been looking forward to doing it again this year.

The hibernations are a treat because they come at a time when you haven’t seen any bats for a while. In our group you get invited to attend one if you have been particularly active in the group that year and if there is space in the limited number that these surveys are suitable for. So if you get an invite, you want to go, wet and windy or not.

I kitted myself up. Sunday was my first outing in my new thermal underwear. Like a secret mime artist I thermalled up, then wore a t-shirt, trousers, a fleece, waterproof trousers and a fat, high-viz waterproof jacket. I had woolly gloves and waterproof gardening gloves over the top. I had spare gloves, spare hoodie, spare long sleeved top, spare jumper. I had hiking boots and wellies, and a cag.

What would later occur to me was that wet days tend to be warmer than dry winter days and I would spend some time either being way to hot, or faffing about in the dark trying to get rid of a layer or two.

Baptiste picked me up at 09:30 in his Ford KA. Ever notice how many ecologists/conservationists drive Ford KAs? We picked up Andrea from Salford Quays and drove through the morning rain to the first site near Chorley.

As we drove up the narrow country path to the meeting point, a large 4-wheel drive met us coming the other way and refused to pull over and let us pass. So Baptiste had to carefully reverse his KA back down the length of the path. The driver of the other car said thanks on his way past as though we’d had a choice.

There were 8 of us on the survey: Steve, Fi, John, Brian, Leanne, Andrea, Baptiste and me. We suited up and strode off into the woods to the remains of some industrial buildings that have been a hibernation roost for many recorded years.

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The woodland was soaked with rain and rich in mosses and broom everywhere you looked, all taking advantage of the nutrients and growing on top of one another. Even the buildings we surveyed had stands of saplings growing from their roofs like bad hair.

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We split up into two groups. My group took the main building, gated off to protect the hibernating bats from inquisitive people. It was wet inside too, the rain finding its way through the old stones and dripping down our necks and in our eyes as we peered into every crack and crevice.

The technique for finding a hibernating bat comes more from practice than anything. You shine your torch into a space and peer in. You move the torch to illuminate the space from all angles and you try to focus and unfocus your eyes to take in every detail of what generally all looks like variations of the surface of whatever the structure is made of.

It’s hard. When you’re first shown a bat in these circumstances you may struggle to see it at all. “Look at the back past the sticking out bit of stone” someone will say. You can’t see it. “Move your head up a bit, you need to get right in as far as you can. See it now?” You still can’t. You don’t believe there is a bat in there. Someone else has a go and they see it. You try again. After a while you see it. A bit of leg and a slither of fur, 6ft away in a dark crack that you seem unable to keep your torch light on for more than a split second. “I see it!” You say. “Great!” They say. “So what do you think it is?”

The idea that you could ID a bat in those circumstances seems ridiculous at that point. You suspect they’re taking the piss. But they aren’t. What you discover is that if you over come the overwhelming appearance that it wouldn’t be possible to ID the bat, and think instead of the ID features (fur colour and shagginess, face colour and shape, ear shape and texture etc) you can make positive IDs to species in these conditions.

There were no hibernating bats in this building, or in the other structures that the other half of the team were checking. There were however, as I stuck my head up a hole and wriggled round to investigate a space with my torch, several herald moths and loads of mosquitoes which began dancing excitedly as they sensed the CO2 in my breath.

#herald #moth

But no bats. Not even in Simon’s Crack (there is a tradition in the group of name the locations of first bat finds after the person who found them), a rare and disappointing result. But our fortunes would improve later…

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We squelched back through the woods to the cars. The stream near by was hurling up water over the rapids. Quick snack then back on the road. The drive to the second site at Edgeworth, over undulating roads, through the pouring rain was a soporific one and I watched rivers of water running in the gutters on the road side as we drove. One drain had rain water fountaining up out of it.

It made me think of the SuDS (Sustainable Drainage Systems) training session I’d had at work on Thursday and I tried to imagine what mitigation you could put into place here to make more of the rain stay where it landed.

We all met up again at Edgeworth and stood eating our lunch. I had a cheese, pickle and rain sandwich and pocketed a flap jack and a bottle of squash in my giant high-vis for later. We donned our caving helmets and got our trudge on along the path to the mouth of the cave. The entrance is set in a gully that to a fan of fantasy fiction strikes you as being the perfect place for an ambush. But there were no bandits, orks or mountain trolls, justs 8 bat workers in a variety of coloured caving helmets and a mish-mash of waterproof coats and overalls.

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Last year the cave entrance had a beautiful façade of icicles hanging above it, today it was running water and we descended through a beaded curtain of water into the gloom. One look back at daylight then off we trekked into the cave.

#icicle(above: last year)

 

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The cave network is a spacious one. Not much crawling around needed here. They have clearly seen some action too. There are the remains of parties gone by in the form of spent candles, discarded beer cans the brands and colours of which you don’t recognise, and extensive graffiti which looks like its been produced with a tin of paint and a brush rather than a can. The caves themselves remind me more than anything of the 2p machines you get in arcades where you attempt to push many 2ps over the edge by inserting one 2p, creating shelves of over hanging coins. The whole cave is like a giant 3D version of this with giant square coins that teeter, dead still and silent above you in the dark, and litter the floor, the result of past jackpots.

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#Lancashire #cave

#graffiti #cave #Lancashire #advice

The piles of fallen rock shift and slide about under your feet as you scramble as carefully as you can over the mounds, mindful that nothing you see is reliably secure. Your mind wants to reach out and pluck this or that stone splinter from where it juts between layers but your inner monologue repeatedly refuses it, imagining the ruinous domino run it could initiate.

#Edgeworth #cave #Lancashire

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We began the painstaking process of investigating every crack with our torches. You get into a rhythm, moving along a wall, crouching and stretching to see in as much as possible. Occasionally you look up and see 7 other torch lights moving around in the large, dark space. It looks absurdly surreal and strangely beautiful. There’s something satisfying about being somewhere like that with a specific job to do.

As time goes on you all start to develop what I refer to in my head as drunk legs and the sound of someone landing on their bum isn’t uncommon and is always followed by: “I’m alright!” Your arms get tired too as you push yourself up or balance on a boulder.

We found 18 bats, an excellent result. There were 13 Whiskered Brandt’s and 5 Daubentons. With each bat that is found, everyone has a look and tells Steve what they think it is and why. Then he tells you what it is and why. Impressively we were all right more than we were wrong. It’s so useful having this many of these similar looking bats together. Being told a Whiskered Brandt’s has a darker face than a Daubenton’s is nothing compared to seeing one, then the other, then other etc…

Steve has a habit of acting as though you might have got it wrong when you give your answer, forcing you to be bold and confident in your ID’ing. One example was where there were two bats hanging out in the open. I identified them both as Whiskered Brandt’s and he replied: “Really? Because one looks very different to the other”. “Dammit” I thought. Other people suggested one Whiskered Brandt’s and one Daubenton. “I did think they looked different” I chastised myself. But they were, as it turns out both Whiskered Brandt’s and I smiled satisfied in the dark.

#whiskeredBrandt #myotis #bat #Lancashire #cave #hibernation

#Edgeworth #cave #Lancashire

About an hour from the end I found my first hibernating bat. I hadn’t had any firsts the last year so it was an ace moment when I saw that clawed foot and wing between the rock. You get used to seeing rocks that look like bats. There are rocks in those caves that look more like bats than the bats you’re shown. I double checked. I was sure and called Steve over. This was an especially exciting find as it took our total for the day over the existing record and we successfully high-fived (no mean feat in the dark) in celebration.

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When we left the caves it was getting dark. We retraced our steps back to the car, torch lights bobbing along in a line and headed to the local pub for a celebratory drink then home. A excellent day, a productive survey, and a fantastic lesson in Whiskered Brandt and Daubenton’s bat ID.

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