Badger Clans
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Encounters in the wild
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Although a few badgers live alone, most live together in groups
of between 2 and 20 individuals. A group of badgers living together is called a
clan (or sometimes a cete). A clan
is usually made up of several adults and their cubs. A typical clan
may have about 6 badgers.
The clan will normally occupy a single main sett - which might be
quite large - and this will normally towards the centre of their
territory. However, the sett may also include other subsidiary
setts, which are used from time-to-time - for example by nursing
mothers, or badgers who live nearby on the periphery
of the clan society.
Dominance
Within each clan, there are usually one or more lines of hierarchy or
dominance between badgers.
The clan is usually dominated by a single adult male (boar) - normally an
older larger boar. If there are multiple females of breeding age, they may have
their own hierachy (subordinate to the males); with the most senior female being
the one which is most likely to breed successfully and produce cubs. In large
clans, sometimes two (or very rarely three) females will produce cubs, but this
is a very rare event.
Dominance may also extent to feeding behaviour. If two or more badgers come
across a food item, the more dominant animal is likely to try to seize the food
item for itself. This is why you sometimes see badger carry food off away from
the group so they can be more certain of eating it, without it being stolen away
from them.
Minor arguments may develop between badgers when feeding together; sometimes
with some shoulder barging and minor growling/aggression taking place. Serious
fights rarely seem to develop over food.
Badgers (especially males) may fight to achieve dominance over the group; or
to deter an intruding badger which is perceived to be a danger. These fights
seem to happen more frequently in areas of high badger density; and older male
badger tend to show more rump injuries than younger animals. It seems very
likely that such fights develop either in the defence of their territories or in
defence of their females or in response to other social tensions (such as
overcrowding).
These fights can be savage affairs, sometimes starting with damage to muzzles
and necks, often turning into major fights which cause significant injuries to
the rump and back (above the tail). Bite marks on the rump can be a simple as
minor puncture wounds or be as serious as large wounds which discharge infected
fluids (pus). These bite wounds can often penetrate deep into and even through
the lower layers of the skin, and provide multiple points where infection can
enter. On some occasions, these bite injuries can result in large open wounds
which look terrible to the untrained human eye. A skilled experience vet may be
able to treat such wounds if there is expert help on hand to capture the injured
badger in a suitable rescue cage. However, badgers seem to have a powerful
immune response and many badgers cope very well with wounds which may be lethal
in different animal species. Eventually, assuming the wound heals itself (or is
managed under veterinary care), the wound can turn into very thick scar tissue
which may have less dense hair growth. Apart from the badger appearing to have a
partly bare bottom; the scar tissue may then provide some additional protection
in future fights.
Dispersal
In the clan, badgers are definitely "group-living" animals, but
they do have a "pecking order" in the
hierarchy. Mostly, the clan will be dominated by a single adult male
(boar, who will try and control all the females (sows) for breeding purposes. As young boars grow bigger, they
may
try and rise up the pecking order to become the dominant boar. This
process will result in some of the younger badgers leaving or being ejected
from the clan, and they will either have to force their way into a
nearby clan, to form their own clan or to live alone. Sows also have
their own pecking order, and may also try and rise up the hierarchy to
become the senior sow. It is believed that fewer females are ejected
from the clan, but some may leave voluntarily.
When badgers leave their original (also known as natal) clan, this is known
as dispersal. The most common age at which this happens is at about 2 years of
age; and the likelihood an animal will leave is generally related to how stable
the clan is as a group. The more stable the habitat and social dynamics of the
clan, the less likely dispersal becomes. There has been a long term study of
badgers around Oxford, and scientists have discovered that males have a greater
tendency to disperse than females. They also found that 36% of individual
badgers never left their original clan. There was also some evidence that, in
some circumstances, sows may leave the clan in coalitions of two or three
animals. In terms of how far animals actually went; the overwhelming majority of
animals moved no more that two or three home ranges away. In other words; of
those badgers who disperse, more or less all of them remain within about 3km of
their birthplace.
Note that dispersal is the process by which a badger moves from one family
clan to a different family clan on a permanent basis. This is different from
when a badger temporarily goes into the territory of a different clan for short
periods of time to mate. Due to relatively low dispersal distances, it seems
clear that, at the local level, badgers may be heavily inter-bred. This may be
why there is some anecdotal evidence that people have seen examples of
erythristic (red/brown) or albino (white) badgers more commonly in certain
places.
Common Scent
Members of a clan can recognise each other by their smell. The badger
has a special opening (called the subcaudal musk gland) under its tail, which
produces a smelly liquid called musk. This musk is a soapy
cream-coloured fatty substance (a bit like margarine in colour and
texture). Each badger has its own unique combination of chemicals in
its own musk; so it will have its own unique smell. Hence, to a badger, with a highly
sophisticated sense of smell, every badger smells slightly
different. However, the different scents given off by all the
badgers within the clan seem to be more similar to one another than the scent
given off by badgers from outside the clan. The scents differ between males and
females; as well as during different seasons of the year and when each
individual badgers is receptive for mating. A keen badger will be able to tell a
lot about another badger by the scent that it gives off.
Badgers also smear their own scent on to other badgers in the clan - this
process is known as allomarking.
Most or all the members of a clan will be marked with the musk of the
dominant male badger. He does this, it is believed, because he wants to mark
those individuals as belonging to his clan. When one animal marks all the other
animals this is known as sequential allomarking (or sometimes one-way
allomarking). Whilst much more commonly done by the dominant boar, other boars
may mark females if they have just mated with them (possibly to try to deter
other males from trying to mate with her too).
There are also examples of two badgers trying to mark one another - this is
known as mutual allomarking.This appears to happen much less frequently. In some
instances it appears to occur when cubs are learning behaviour from adults. It
is not known whether a cub scent marking an adult has any real significance or
not. There is a plausible suggestion that cubs may learn to scent mark before
they produce any gland secretions. The suggestion is that they do not start
producing gland secretions until about four months old; which would tie in with
them starting to move around the territory. Observations of cubs in rescue
centre seems to suggest that cubs which are in the vicinity of a badger scent
are more relaxed. Proving cubs with badger playmates or soft toys they can scent
mark seems to make them more relaxed.
By "swapping smells" like this, each badger ends up with a
smell that is special to his or her clan. Accordingly, each badger
has their own unique smell, plus the common odour of the clan.
Importantly, though, badgers don't just use their musk to mark each other. They also
stop from time-to-time on their travels to leave scent on the
ground - especially on their badger paths. They do this by squatting
on the ground and smearing musk onto a rock, a tuft of grass or
other prominent vegetation. This helps the badgers to find their way around their
territory
using their
sense of smell. In this way, badgers find it easier to follow
regular trails to and from good feeding grounds, as well as avoiding
encroaching on territories of other neighbouring badger clans. In
the case of a dominant male, it would seem that this would be
intended to mark the territory. In the case of a female who is
receptive to breeding, it would seem likely to indicate her current
status to nearby males. The subcaudal musk gland is about 2.5 times larger in males than
in females; and contains 4 times as much musk as the same gland in
females. It is assumed that as well as using the musk to create an
overall clan odour, dominant males use this to "claim" other badgers
as being in their clan. In females, the scent provided by their
subcaudal gland may change throughout the year - probably indicating
whether they are receptive to mating. Badgers also have an
additional pair of scent glands, which produce a dark brown fatty fluid which
has a powerful and rank musky smell. This pair of glands is located just inside
the bottom (anus). They also have musk glands on their feet - and this will
help badgers follow badger paths by their scent. It is suggested that these
scent glands on the feet will also leave scent on tree trunks which badgers use
as scratching posts. The height marked by the feet could provide a useful guide
as to how tall the home badgers are, if the scratching post is visited by
neighbouring badgers. The use of scent on their badger paths and within their
territory greatly helps a badger finds it's way around where it lives. Because
it is familiar with the scent of other clan members; this can help it get back
to its home sett quickly. There is some evidence that badgers released into an
adjacent territory may have some understanding of how to get back to their home
territory (albeit after some degree of exploration). However, badgers release in
areas they have never been too or containing badgers they have never scented
before pose a great risk; as they have no scent trails to help them get home
again. Both these types of scent are used to denote membership of
the clan; and to mark the territory/range as belonging to that particular clan;
and hopefully deterring other badgers from coming in to mate with
females or steal food. Perhaps for this reason, allomarking has been observed
more commonly during the mating and cub-rearing seasons. Generally, males
perform allomarking much more frequently than females. However, both sexes
will "over-mark" scent left by other badgers on some occasions. It is possible
that this is done to try and re-claim ownership of a territory. Otherwise, it
may be done by females to raise their profile as being available for mating; or
to claim a small part of a main sett as being exclusively for her and her cubs.
Returning Badgers to the Wild
If a badger leaves the clan it quickly loses its distinctive
"clan" smell. This can be a problem for animal rescuers,
as they need to rescue an injured animal, get it treated at a vets,
repaired, recuperated and returned to the clan as soon as possible.
On return to the
clan, if the badger is missing its expected clan smell it may be
dealt with as though it is an outsider. It may be bullied
by other badgers, and possibly ejected from the
clan or attacked (or maybe even killed) by other badgers. In many
badger releases, the repaired animal will be placed in a secure cage at the
planned release point and observed to see if other badgers find it. If the wild
badgers seem to be agressive towards it, this is not a good sign; and the
release may be abandoned. If the wild badgers are interested and no agressive;
this may well suggest that they recognise it as one of their clan; in which the
cage can be opened by pulling a remotely operated release pin to open the door.
Otherwise it might be possible to "puppy-walk" the
badger around the territory, so the wild clan gets used to the
repaired badger smell once
again. This will make it a little more likely the other badgers will treat
the returning badger kindly, and not as a threatening intruder.
The other option is to place a rescued baby badger into a new
family with other cubs; and then release them into a new sett in the
autumn.
This is an enormous programme of work by the animal rescue
organisation; and it is only possible to create new badger families
with young cubs. This method is easiest where there is an existing empty sett
already, and you can
place a group of rescued badgers into it as a new clan.
Academic Note: |
Journal of Animal Behaviour - Volume 97 No 1/2 - May
1986 |
Scent Marking with Faeces and Anal Secretion in the
European Badger (Meles meles): Seasonal and Spatial Characteristics of
Latrine Use in Relation to Territoriality |
T. J. Roper, D. J. Shepherdson and J. M. Davies |
© 1986 BRILL. |
Abstract Badgers |
(Meles meles) defecate and scent mark in open pits
('dung pits') which seem to have territorial significance. We carried
out a year-round survey of badger defecation sites in order to assess
seasonal and spatial characteristics of site use. Our results show that
badgers defecate at two different types of site, which we refer to as
'latrines' and 'temporary defecation sites' (TDS's) respectively.
Latrines are relatively large aggregations of dung pits (up to 25
separate pits) that are visited year-round; they are largest in spring
(April) and autumn (October); they are more numerous around the
perimeter of a territory; they are associated with fences and roads; and
they often contain anal-gland secretion as well as faeces. TDS's, by
contrast, are single dung pits or small aggregations of pits that are
used only once or twice and are then abandoned; they are most numerous
in mid-winter (December and January); they are scattered throughout the
territory both close to and away from fences and roads; and they do not
usually contain anal secretion. Spatial and seasonal changes in
frequency of TDS's are shown to correlate with food availability and
with foraging behaviour, and we conclude that TDS's have no special
function beyond elimination of faeces. Latrines, however, do seem to
have communicatory significance, and we conclude that they are concerned
with territory defence. Since seasonal changes in latrine use correlate
more closely with mating than with food availability we suggest that
territoriality in badgers may be related more to defence of oestrus
females by resident males than to defence of food resources. |
Academic Note: |
Journal of Zoology Volume 237 Issue 2, Pages 227 -
239 |
Dispersal and philopatry in the European badger,
Meles meles |
Rosie Woodroffe* , 1 , D. W. Macdonald 1 and J. da
Silva** , 1 1 Wildlife Conservation Research Unit, Department of
Zoology, South Parks Road, Oxford OX1 3PS, UK
*Department of Zoology, Downing Street, Combridge CB 23EJ, UK
**Department of Biology, Laurentian University, Ramsey Lake Road,
Sudbury, Ontario P3E 2C6, Canada |
Copyright 1995 The Zoological Society of London
ABSTRACT |
In comparison with other carnivores, European
badgers, Meles meles L., show an unusually high degree of natal
philopatry. In this paper, we present data on temporary and permanent
movements between groups, in both male and female badgers, in a
moderately high density population. A relatively small proportion of
males dispersed, alone, to neighbouring territories. Dispersing males
were larger than those remaining in their natal groups, and following
dispersal they had higher testosterone titres and maintained testicular
activity for a greater part of the year. Circumstantial evidence
suggests that immigrants were the principal breeding males in their new
territories. Dispersal was slightly more common in females, which
dispersed away from large groups, where their chances of breeding were
relatively low. Females dispersed in coalitions of 23, over longer
distances, to territories occupied by single females. Resident females
disappeared following the arrival of the immigrants, suggesting that
territory 'takeovers' may have occurred. Members of both sexes also made
temporary 'visits' to neighbouring territories, probably to obtain
extra-group matings. Comparison with other badger populations suggests
that the frequency of male dispersal declines at high population
densities. In contrast, there is no effect of density on female
dispersal, which occurs only rarely in some other populations. We
suggest that the pattern of female/female competition is too complex to
be explained solely in terms of variation in population density. |
Academic Note: |
Mammal Review Volume 18 Issue 1, Pages 51 - 59 |
Comparison of dispersal and other movements in two
Badger (Meles meles) populations |
C. L. CHEESEMAN 1 , W. J. CRESSWELL*, S. HARRIS* ,
P. J. MALLINSON 1 1 Ministry of Agriculture, Fisheries and Food,
Worplesdon Laboratory, Tangley Place, Worplesdon, Guildford, Surrey GU3
3LQ *Department of Zoology, University of Bristol, Woodland Road,
Bristol BS81UG To whom correspondence should be addressed. |
Copyright 1988 Blackwell Publishing Ltd and The
Mammal Society |
ABSTRACT |
The dispersal and other movement patterns in two
Badger populations, one in rural Gloucestershire and the other in
suburban Bristol, are described and categorized into nine different
types of movement. Movements were less common in the high density Badger
population in Gloucestershire, but disturbance increased the likelihood
of movements occurring. In the lower density Bristol population, where
the social structure was more fluid, movements were more common.
However, in both populations truly itinerant Badgers appeared to be
rare. More male than female Badgers moved, but for each type of movement
there was no difference in the distance moved by males and females.
Movements were rare in animals less than a year old; most movements
occurred in sexually mature animals, i.e. those more than 2 years old. |
Badger Encounters in the Wild book |
|
Superb
book of Jim Crumley's encounters with badgers in the wild in Scotland. The quality of the writing is superb.
A great read. Click here to buy:
Encounters in the wild
|
|