If you see bats flying around your house or garden in the evening before it goes dark it is a good chance they are the most common species ‘Pipistrelles’. The numbers of all species of bats in the UK have declined massively since the mid 1900s. Much of the decimation was cause by a chemical call Lindane which became widely used to treat roof timbers for protection against insect damage. The fumes from this lethal chemical would remain fatal to bats for up to thirty years after treatment. It was finally banned but not before it was almost too late. On one occasion approximately 30,000 bats were killed in one single colony when the roof of a church was treated. The bats were carried away in wheel barrows full. Because bats only produce one young each year and not every year it doesn’t take a mathematician to work out how long it would take for that particular colony to recover. Whilst bats were once common in the countryside they have declined, now because of a more recent threat, the chemical sprays used on crops. These sprays are designed to kill the very insects that bats depend on for their food. There are various myths about bats which are not true, one is that they are blind, hence the saying ‘as blind as a bat’ in fact bats have very good eyesite in daylight and after dark use their echolocation system to see equally well if not better. The other is that they get tangled in your hair which is also not something which happens regularly. It may be true that it has happened on occasion but they don’t make a habit of it. All bats belong to the ‘order’ chiroptera meaning hand wing which what the bats use to fly with such great precision and agility. The bones of the wing are actually the outstretched fingers of their hands and between them is skin which forms the wing through which air cannot pass. They also have a thumb which they use as a hook.