Honest Truth Bats? Forget any hang-ups. They are amazing...and munch midges
They have been revered and reviled. Ancient Egyptians worshipped bats, but millions today are terrified by Bram Stoker’s Dracula, a vampire-cum-bat. Paul Gill, technical director at Rocket Ecology, tells Sally McDonald the Honest Truth about these iconic
How many species of bats are there in Scotland?
There are nine, or possibly 10, bat species in Scotland. There is a lot of contention about the 10th – Brandt’s bat, whose DNA was once found in Galloway. The Scottish species are: Common (or Bandit) pipistrelle, Soprano pipistrelle, Nathusius’ pipistrelle, Brown Long Eared, Noctule, Leisler’s, Daubenton’s, Natterer’s, Whiskered and, possibly, Brandt’s bat.
Which bats are the rarest?
In Scotland, the rarest bat species are the Noctule bat, Leisler’s bat, Whiskered/Brandt’s bat, and Nathusius’s pipistrelle.
Why are bats important to the natural world?
They are incredible creatures, using their “echolocations” to navigate complex structures and locate their prey. They can feed on thousands of biting insects every night – a pipistrelle can consume 3,000 midges per night. Bats are the only truly flying mammals, achieving flight with the same basic forearm and hand structure as us. One of our Scottish species holds the record for migrating at least 2,486km from Russia to the French Alps. Also, research on bats’ communication by high frequency ultrasound “echolocation” has led to the development of ultrasonic devices for the visually impaired.
Why are bats protected?
Bats are protected because they’re threatened, vulnerable and rare. Due to their small size and slow reproductive rates, they’re at an even higher risk. All bats and their roosts are legally protected in Scotland. Because bats return to the same places every year, a bat roost is protected even if there aren’t any there.
What are the main risks to bats?
Habitat loss, building and development work and climate change, are some threats faced by bats in Scotland. Domestic cats are a threat too. On average they kill about a quarter of a million bats a year in the UK. It’s an offence to deliberately or recklessly kill, injure, capture or harass a bat, or to disturb or obstruct its roost. It’s also an offence, whether or not deliberate or reckless, to damage or destroy a bat roost. So, if developers don’t act to prevent affecting bats and their roosts, they run the risk of committing an offence – with a maximum penalty of £5,000 and six months’ imprisonment.
Why do bat experts carry out surveys?
We carry out surveys, not only to catch a glimpse of our favourite animals, of which there are an incredible 1,400 species, but to understand where they live, either in roosts during the day and hibernating in the winter. We also want to know where and how they feed and travel at night. And surveys help protect bats from threats, monitoring how populations change as their roosts, the woodland and aquatic habitats bats favour for feeding, and the river valleys, hedgerows, and woodland edges they use to navigate, are eroded by land-use changes, tree-felling and insensitive development. Development surveys are also common, investigating whether bats will be affected and how roosting could be encouraged once work has been completed.
How frequently does this happen and what is involved?
Whenever a development could affect bats a survey must be completed. Bats roosting in your home is rarely a problem, and help is available from NatureScot or the Bat Conservation Trust, who can send licensed bat specialists to find a solution. Most commonly, bat detectors are used, transforming high-frequency bat calls and “echolocation” noises into sounds humans can hear. If anyone is interested, the Scottish Bat Project launched by the Bat Conservation Trust organises projects where volunteers are trained to get involved in conservation and surveys.
What should a property owner do if they want to develop a site?
When planning to build, develop, alter or demolish a property or piece of land with trees, a Preliminary Roost Assessment to determine whether bats could be affected should be undertaken. Initial surveys will check for suitable places bats could roost, with follow-up surveys to determine if bats are present. Ideally if bats are roosting, interfering with them would be avoided. If unavoidable, a licence may be granted to disturb or destroy a roost. Even then, suitable roosting features would need to be factored into the development.
What is your favourite bat?
Scotland’s largest bat – the Noctule. They come out early, fly high, and are primarily tree dwellers. Their metallic chirping sounds are so loud colonies can be heard through bat detectors up to 300m away on hot days. They “shout” four times louder than the legal limit of a nightclub, but we can’t hear it because of its high pitch. If we could hear their calls without modification, they would seriously damage our eardrums. The loudest bat in the world is the Lesser Bulldog Bat which has been recorded at 137 decibels, 17 decibels above the very loudest rock concerts!