Artificial Setts
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An artificial sett (sometimes known as a badger bunker)
is a sett constructed by humans to be suitable for badgers to move into.
In a few rare cases people may build setts with the hope that some badgers turn
up and occupy the sett. This is what the well-known countryman Phil
Drabble did on his land as back back as the 1970s. Realistically, there is often an element of
"force" on our part to compel the badgers to use their new home.
The two main reasons why people would want to force badgers
into using an artificial sett are because:
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people propose to destroy their existing sett to make
way for a road or a property development, or
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their existing sett is at serious risk of collapse
or attack by badger baiters; and they need a safe,
secure home
However, badgers and their setts are protected by the
law; and before any badger sett can be damaged or destroyed a badger
licence needs to be issued to define precisely what is allowed and at what
times of year. Without the grant of a satisfactory licence, destroying a
badger sett is illegal.
If a main badger sett is threatened, there may be
serious problems as
the badgers will be extremely reluctant to move elsewhere. The chances of
success may be enhanced if there is large alternative sett nearby. However,
generally outlying or subsidiary setts are too small for permanent
occupation by a group of badgers, and may be in a situation where it would
be difficult for them to be enlarged.
When it is a main sett that is being threatened, an artificial sett
(or a badger bunker) will have to be provided, rather than just trust to luck that the badgers
will take up permanent residence in a another sett within their territory. Provided that the artificial sett is well
constructed and in a suitable location, it is likely to be adopted
by the badgers, eventually. Many natural setts are
excavated in man-made features such as railway embankments or old quarries
anyway, and artificial fox earths are often taken over by badgers. The
advantage of taking over or enlarging existing tunnels can be very useful,
as those tunnels may already have "proven" themselves as having
enough ventilation, safety from predators and interference; and,
importantly, being unlikely to flood.
If an artificial sett is constructed, the badgers are
normally phased into it over several days. As well as being left to
explore it on their own for a few days, they may be lured into exploring
it with food so they see the new tunnels as a friendly, safe area. At some
stage, the badgers may then be excluded from their own sett (by the use of
one-way gates; and be forced into the new sett. Volunteers may then pen
the badgers in to the new sett, and provide feeding and watering them for a few
days, whilst the penned area is gradually enlarged. Hopefully, after a few
days of acclimatisation, the badgers will have got used to the new sett
and will be content to remain there. That said, it is not uncommon for the
badgers to begin enlarging the artificial sett almost immediately; and the
appearance of new tunnels and exit holes may need to be monitored closely
if the new sett is still in the vicinity of the building works. As soon as
the badgers are installed in their new home, the old sett will need to be
thoroughly destroyed or securely stopped up (e.g. with high-strength
concrete). This phase can be critical, and the badger consultant will
normally be very keen to stop the old sett as soon as the badgers are in
their new sett. As badgers have such superb digging skills, no-one will be
certain that the badgers are truly confined in their new sett; and they
may suddenly appear out of a newly dug exit tunnel; and return to their
old sett before it has been destroyed.
As for how to construct an artificial badger sett, the
most common arrangement will be for a couple of nesting chambers to be
excavated in a sloping woodland, and for these to be connected together;
and have at least a couple of tunnels (made from concrete pipes) which
connect the chambers to the outside world. Some of the underground tunnels
ought to have diggable gaps, to allow the badgers to expand the sett in
due course. Joints in the tunnels should be overlaid with very thick
water-proof plywood (to prevent soil trickling down into the tunnels as
the soil is re-laid). The chambers should also be capped with thick
water-proof plywood.
The nesting chambers can be made from water-proof plywood
or breeze blocks cemented in position; and should be big enough to allow
badgers to sleep in a "big-hug" arrangement, in a deep layer of
bedding materials.
The tunnels should slope to prevent water logging, and
there should be suitable soakaways at low points in the tunnels system,
and beneath pipe joints. It is also a good idea to ensure that the two
entrances are at different horizontal levels; as this may well encourage
fresh air-flow through the sett in a "chimney" effect. Depending
on the concrete pipes actually used and the ground conditions, it of often
an advantage to lay some pipes with unsealed ends, to allow badgers to dig
into the surrounding woodland. Remember that if the badgers can not expend
their sett, it will be unlikely they will be able to cope with
"bonus" years when lots of cubs survive, due to their being lots
of year-round food and good water supplies.
Importantly, though, the construction of a new badger
sett may become well-known; with the risk that the sett will become a
target for attack by badger baiters. For this reason, it is customary to
seal the top of the badger sett (i.e. tunnels and nesting chambers), with
large areas of 8mm weld mesh and/or a very rough concrete cap. Once set,
the concrete cap can then be overlaid with a thick layer of soil and
vegetation cover to make the new sett blend into its surroundings.
The construction of a new badger sett is one of the most
valuable things done by Badger Groups
in the UK; and most will be well able to do the work themselves - either
alone or in conjunction with any retained badger Consultant.
However, the work can be very difficult in certain ground conditions; and
we would urge all construction companies to use their considerable
resources to help badger groups. Making donations of "skills" to
registered charities (like badger groups) is a very public-spirited thing
to do; and it ca result in good local publicity, which will have a
beneficial effect when it comes to selling the houses.
We would also urge members of badger groups to
"spread-the-word" to the pro-badger community. Children and
Students are increasingly being given credits for charitable and community
work; and we'd like to think that many young people would be keen to
"do something" for the natural world, that their parents (and
grandparents) have often treated badly.
Graveyards and Churches
On rare occasions badgers have caused problems in
graveyards and with churches; when their digging can risk the collapse of
walls and monuments; and possibly result in the distressing exhumation of
human bones.
In those serious circumstances, an artificial sett is a
possibility; although great care needs to be taken to exclude badgers from
the church environment thereafter. Issues with Fencing
will become very important - especially if church visitors have a tendency
to leave gates open.
Railways
Railway embankments can become common places for badgers
to dig setts.
If the badgers are digging into a cutting, all that it
needed might be suitable badger-proof fencing to keep them off the
permanent way (especially the track).
If they are digging under the tracks or into an
embankment on which the track stands, this is more serious; and it may be
necessary to exclude the badgers from the whole embankment. Apart from the
fencing issue; the badgers may simply be tempted to simply re-dig another
sett right next to the one which was closed. If it is believed that the
badgers will do this, it might be possible to cover the whole embankment
with a strong galvanised wire netting which will prevent the badgers
digging any tunnels.
Railways are controlled environments, so there is
necessarily a whole raft of health and safety guidelines and work
practices which can make badger management more difficult on the railways
than many other places.
Roads
The situation with roads is sometimes easier than with
railways.
Whilst the public nuisance of closing a road for road
works may be very great, and rules and regulations concerning works may be
less onerous.
At one time it was almost route that any badger sett or
tunnel which went under a road would be destroyed. However, in recent
years, other options are being thought about.
If, for example, a badger tunnel goes under a road, that
tunnel might be at risk of collapse if it undermines the road which
carries the heavy traffic above. A more modern solution might be to
convert the tunnel into a secure concrete wildlife tunnel, which will
allow badgers to pass under the road in safety; whilst the heavy traffic
thunders overhead in equal safety.
If part of a badger sett is under a road or in an
embankment, it might be possible to cover the top of the sett with a
series of reinforced concrete lintels, and allow the badgers to live under
the road.
Whilst this might appear strange at first, you have got
to consider that wild badgers live where they are happy living; and if you
exclude them from their home; they often just dig another one immediately
next door. You are often better to try and leave badgers in situ, rather
than have to deal with repeated badger tunnels and digging attempts along
a short stretch of road.
Levees and Flood Barriers
The risk with badgers digging into levees is that the
tunnels may so weaken the earth barrier that it collapses in the event of
a flood; or that it allows such rapid water seepage that the levee leaks
too quickly
In such situations, the situation can become very
difficult; and experts from many different agencies may need to consult on
the matter; before any satisfactory solution can be thought through and a
badger licence obtained.
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