The bat man

With our bat ecologist, I am climbing the spiral staircase of Craigievar Castle, leaning outward as it narrows towards the top. I try not to think that we are about 20 metres above what would have been the courtyard and will soon emerge outside onto the platform at one of the castle’s highest points. Instead, I think about what I might do this evening. A film? At the moment, any cinema seems quite far removed from Craigievar Castle.

It seems far removed, too, from the time I was sitting down below on the lawn with the ecologist and others, swaddled in multiple jackets, on a deckchair with dusk falling around, peering up at the darkening eaves of the castle, looking to pinpoint where bats exited from the roof and walls.

What movie would I see, I wonder? Like many others, I have enjoyed the Batman films, and the latest one might be a topical choice. It makes me wonder about the representation of bats in popular culture. The bat is an enduring symbol but it seems to me it is firmly placed in the hinterland between good and bad – it’s got a bit of an image problem.

In almost all the popular horror movies I grew up with, bats featured prominently. Cinematically, they were the go-to backdrop for spooky situations. They poured out of cave entrances; in cartoons, they flapped about before flying straight at you and opening wide their fierce yellow eyes. There is the connection with Dracula of course, inspired by the vampire bat of South America (incidentally, vampire bats have a fascinating ecology, well worth looking into themselves!). And then there is the perennial cliché of a bat entangled in one’s hair.

Little wonder then, that bats get a bad deal. But their problems extend far beyond their negative cinematic image. Compared to what they once were, our woodlands are presently much diminished, and our trees are rarely left to age to the point where they accumulate fissures and cavities that suit bats for roosting. Because of this habitat loss, combined with the effect of pesticides, our insect numbers are plummeting – there is now less food for bats to eat. Our churches and halls are modernised, our buildings are insulated against heat-loss ... fewer and fewer spaces remain for bats in that crucial summer period where they seek warmth to congregate and raise their young.

There are a wide range of views held by the public, from those who are happy to co-exist with bats to those for whom the thought of sharing is anathema. Bats leave guano (poo), just like swallows and house martins do; but since bats can enter into loft spaces and wall voids, this is sometimes less desirable to the house-proud home-owner.

Of course, bats are protected by law. For those wishing to repair or improve their homes, this can present an inconvenient challenge. It may be necessary to get a bat survey done to check for their presence; if bats are found, then contractors are legally obliged to stop works. It can be an expensive business.

Things are no different for the National Trust for Scotland. And conservation repairs are rarely straightforward! This is why I am here, climbing the spiral staircase to the parapet of Craigievar Castle, waiting to stand on the balcony and check the slated roof for gaps. There is a brown long-eared bat maternity roost in an attic of the castle, something which is both an asset and a challenge. With urgent conservation work needed on the castle roof to stop water damage to the walls and rooms below, it is necessary to plan this work carefully and make arrangements so the bats are not disturbed. The repairs have now been postponed until the end of the maternity season, when we will replace the broken slates with ‘bat slates’. These are water-tight but are shaped to allow bats entry to the loft.

Earlier, we had opened the hatch to the loft to check for droppings. Brown long-eared bat droppings are longer, shinier and more knobbly than pipistrelle droppings for those in the know. Greasy marks were observed at intervals on the wall. Brown long-eared bats like the ridge beam of a room and will hang from this as well as hide in cavities. It is here they will give birth and raise their single pup each.

When we open the door to the viewing platform, a north wind carries through us and over to the top of the giant Douglas fir we are now level with. Visitors are but dots on the ground. From the parapet, we enjoy a bat’s-eye view of the countryside ... or we would, were bats viewing the countryside in daylight.

Contrary to popular belief, bats are not blind. Their vision is roughly as keen as ours. However, there is not much benefit to keen eyesight in total darkness, which is why bats developed echolocation. This allows them to navigate their surroundings and find prey by emitting an ultrasound and comprehending the returning echo.

The brown long-eared bats will set off from just below where we are now. They come out an hour or so after dusk, much later than the pipistrelles. One at a time from beneath the slates, each following the same flight path direction away from the roof. And from below, it is one of life’s experiences to be under a purple sky with bats buzz-feeding above you, as they swoop and jink, defter than any bird by virtue of those flexible wings, able to twist and turn from this insect to that, even hover. And it feels good to know they can share at least some of our houses with us.