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Badgers are known to inhabit a wide variety of habitats in the UK, ranging from sand dunes in Devon to the Highlands of Scotland and conceivably every habitat in between. However, it is generally accepted that badgers prefer certain habitat characteristics based on underlying geology, slope, cover, food supply and altitude.
Geology
An ideal sett is one that is easy to dig, dry, warm, safe for refuge and breeding, and has structural integrity. Sandy soils are preferred to clays as they have better drainage, and where extensive root networks bind the soil the roof is less likely to collapse. Very heavy clays are avoided. Chalk and Limestone are also preferred as they give excellent drainage and the setts are protected by slabs of hard rock. These substrates aren’t as easy to excavate as sandy soils, although in many limestone areas badgers may exploit the strata of soft material sometimes found below the solid rock.
Slope
In the National Badger Survey carried out by the Mammal Society in 1963, 92% of badger setts were found dug into slopes. There are several benefits to having a sett on a slope, including the ease of removing excavated soil. Also, because rock strata are more frequently exposed on slopes this means that there is a greater likelihood of finding a particularly suitable stratum in which to dig. Sloping land is also usually well-drained, and therefore warmer, drier and in colder areas, a depth below ground is quickly attained which is frost proof.
Cover
Cover around the sett is important as it provides the badgers with an opportunity to emerge inconspicuously, and for cubs to play without being visible to people or predators. Deciduous woods, copses and mixed woodland provide good cover and more than half of all the setts investigated by the Mammal Society’s National Badger Survey in 1963, were found in these habitats. Hedgerows and scrub may also provide adequate cover for setts. Coniferous woods are usually not used because they lack good cover and suitable food is usually scarce. However, coniferous woods are used when other alternatives are not present.
Some setts are found in open conditions, but these are usually in Highland areas where disturbance is infrequent and cover becomes less important.
Food supply
Food supply is one of the most important factors influencing badger habitat use. The most significant single food item of the badger in much of England is the earthworm, which is often abundant in agricultural grasslands. However, badgers also take a wide assortment of other food items that may be found in a variety of habitat types. It is therefore not surprising that many setts are found in areas that comprise a mixture of woodland, grassland and arable. Copses, scrub and hedgerows bordering fields provide the advantages of both adequate cover and food supply.
Altitude
In Britain most setts are found at elevations between 100-200m. This is because land under 100m tends to be intensively cultivated with arable crops and has the highest densities of people. At higher altitudes, human disturbance decreases but the food supply also becomes more restricted.
Distribution in Britain
Optimal badger habitat usually has the following characteristics:
1. Soil that is well-drained, easy to dig and firm enough to prevent collapse.
2. The presence of an adequate food supply throughout the year.
3. Sufficient cover to allow the animals to emerge and leave inconspicuously.
4. Relative freedom from disturbance by people and domestic animals.
An environment in which these requirements are met is hilly, with sandy soils, containing a mosaic of habitats including deciduous forest interspersed with grassland with a high abundance of earthworms. High badger densities occur in such areas in the South West of England. |
