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Badger Setts
Sett
Badgers are common over most of Britain, living in a wide variety of
habitats (though they remain very secretive and elusive mammals).
The badger lives an underground home called a sett. Their setts are
usually situated in small clearings in woodland or copses. The sett will
be obvious to those who know what to look for, as the ground around the
used entrances will probably be free of vegetation, and may be muddy and
may show evidence of badger prints. There may also be evidence of
latrines (holes in the ground) nearby, into which badgers do their poo.
A simple sett is made up of a single tunnel, with a sleeping chamber
at the end. However, most setts have several entrance holes, and lots of
tunnels which link up with each other. The tunnels also link up with
sleeping and nursery chambers. The tunnels may have several interlinking
passages underground; and may also be arranged so as to provide a
constant supply of clean fresh air through the sett in most weathers.
Accordingly, entrances may sometimes be on different levels to help
stale air rise through the sett and be dissipated into the surrounding
woodland.
Well-established setts normally have several entrances which are much
larger than rabbit holes, and which have large piles of earth outside.
The sett consists of large chambers for sleeping and breeding and small
ones used as latrines, interlinked by a maze of tunnels.
A really big sett can have from 50 to 100 or more entrance holes. A
sett this big will have been dug out by lots of badgers, over many
years. There are some setts which are known to be over a hundred years
old. Many generations of badgers have lived in these setts.
One study found a well-established sett in the Cotswolds with
twelve entrances had tunnels totalling 310 metres. It was estimated
that the badgers had excavated 25 tonnes of soil throughout the years
to create this complex. Tunnels can be four metres deep, though most
are less than one metre underground and often follow surface contours.
This helps with air circulation, while ventilation holes sometimes
connect a tunnel to the surface.
Badgers like to dig their setts where the ground is easy to dig.
Sandy soil is a favourite, because it is easy to dig, and it stays drier
than other soils. Chalk and broken limestone is also popular. Badgers do not
like digging into clay, as this is wet and sticky. Even so,
badgers will sometimes make setts in clay, if they can't find anywhere
else.
Badgers also like to dig where there is a good slope, such as on the
side of a hill, or in a bank. Water drains away better on a slope, and
this means that the sett stays dry.
Badgers dig their setts in many different habitats. Woodlands and
hedgerows are good places to find badger setts, but badgers will also
dig their setts in open fields, moorland, sand dunes, old quarries,
abandoned mine workings and
even sea cliffs!
Sett Types
The following sett categories are recognised:
- Main setts
- Annex setts
- Subsidiary setts
- Outlying setts
Main Setts
These usually have a large number of holes with large spoil
heaps, and the sett generally looks well used. They usually have
well used paths to and from the sett and between sett entrances.
Although normally the breeding sett is in continual use, it is
possible to find a main sett that has become disused because of
excessive digging or for some other reason, in which case it is
recorded as a disused main sett. Annex Setts
These are always close to a main sett, usually less than 150 m
away, and are usually connected to the main sett by one or more
obvious, well worn paths. They consist of several holes, but are not
necessarily in use all the time, even if the main sett is very
active. Subsidiary Setts
These often these have only a few holes, are usually at least 50
m from a main sett, and do not have an obvious path connecting them
with another sett. They are not continuously active.
Outlying Setts
These usually only have one or two holes, often have little spoil
outside the hole, have no obvious path connecting them with another
sett, and are only used sporadically. When not in use by badgers,
they are often taken over by foxes or even rabbits. However, they
can still be recognised as badger setts by the shape of the tunnel
(not the entrance hole), which is at least 250 mm in diameter and
rounded or flattened oval in shape.
NOTE Whilst these categories look clear cut, classification might
be difficult in the field. In areas of low badger density, main
setts may be relatively small, with only a few holes, and in
moorland and hill areas, main setts may consist of only one or two
entrances in a rocky cairn. One should not necessarily expect to
find examples of all sett types in a particular area. Many badger
social groups do not have an annex sett, whilst in poor badger
habitat, large areas may be searched without finding a main sett.
These factors must be taken into account when classifying a sett,
and it is important to have an overall view of all the setts in an
area before making a decision on the status of each sett. Other Residents
Badger setts are often used by other animals as well as badgers.
Rabbits often live in badger setts.
Foxes will also rear their young in
setts. These animals live in small setts, or parts of larger setts,
which are not being used by badgers at the time.

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Academic Notes: |
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Mammal Review Volume 22 Issue 1, Pages 43 -
53 |
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Badger Meles meles setts–architecture,
internal environment and function |
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T. J. ROPER 1 1 School of Biological
Sciences, University of Sussex, Brighton BN1 9QG, U.K. |
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Copyright 1992 Blackwell Publishing Ltd and
The Mammal Society |
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ABSTRACT |
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Badger setts vary considerably in size,
ranging from simple single-entrance burrows to complex tunnel
systems hundreds of metres long with multiple entrances and
underground chambers. Data from 19 excavated setts show that
main setts are larger than other setts in terms of area and
volume, and contain more chambers, nests and latrines; but setts
of different sizes and types are built according to the same
basic architectural principles. Little is known about the
environmental conditions within setts, other than that
temperature and humidity are constant in parts of a sett that
are at least 7 m from the nearest entrance. Setts are used for
breeding and as sleeping places and refuges, but a question
remains as to the functional value of large setts. It is
suggested that large main setts allow members of a social group
to avoid one another underground, especially when breeding.
Little is known about the use of other types of sett. |
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