www.badgerland.co.uk
About how badgers live their lives across the UK
Home Blog Animals Pictures Help Seeing Badger Groups Education News Search Shop
Intro Family Food Lifestyle Size Sounds Threats Diary Latin Setts Evidence Habitat Legal FAQ
 
"The man who deliberately sends a terrier to ground to face a badger should resign from the human race."
David Stephen

Breeding

Mating

Badgers normally become sexually mature at 12 to 15 months old, although females may mature a little earlier ansd some males take as long as two years to reach maturity.

Badgers have unusual breeding patterns since mating can take place at any time of the year. The majority of matings take place between February and May, with another smaller peak of mating activity taking place between July and September. The female (sow) is receptive (i.e. in oestrous) for one to two days, during which she may mate with several males (boars).

A boar will go looking for a receptive female. Boars have been observed wandering round a sett sticking their nose into the entrance hole to scent the air for suitable sows; then making a churr noise to see if a female will come out. If there is no reply or the female remains underground; he goes to the next hole and tries again. If the sow emerges, she was then observed to be running rounds in circles. The male often pursues her making a shuffling motion with legs held stiff, his tail held vertically in the air whilst he makes a deep whinnying purr. The overall pursuit may last from 10 to 90 minutes. Encounters which are very short are possibly with inexperienced males or unreceptive females.

Note that this sequences of events may be repeated with different boars, meaning that the same litter of cubs may have the same of different fathers.

Fertilisation

The egg is fertilised normally within the uterus and the fertilized egg is now called a zygote. This now enters the blastocyst stage, where it multiplies to form a hollow ball of cells (called a blastula).

Despite the presence of the first fertilised egg, female badgers still can have further matings with different dominant healthy males.

However, female badgers exhibit what is known as delayed implantation (sometimes called embryonic diapause). Diapause is a dramatic reduction in, or a cessation of, mitosis (cell division). This allows the blastula to be suspended in the uterus for between three and 15 months (15 months is very rare). Each blastula remains in a state of "suspended development" until the female badger has the chance to release a hormone which allows the blastula to move into the womb to implant at the end of December.

The chance to release a hormone is important, because if there is no hormone release the blastula may remain in suspended development until the next year; or it may be reabsorbed by the female and not progress at all. It has been suggested that the hormone produced by the female resides in her fat reserves. When the female goes into her winter torpor (in December), she lives off her fat reserves, allowing the hormones to be gradually released into her bloodstream, thereby causing the triggering of the blastocyst being implanted in the womb. Hence, under-weight sows may not have enough of the hormone to cause the blastula to implant in the womb. Underweight sows may not produce cubs (a good idea if her body condition is not in a good enough condition to produce healthy cubs that she could feed). Hence, it tends to be the more well-fed healthy sows that are more likely to produce cubs;and these are the ones who are more likely to survive.

Once the blastocyst is implanted in the womb, gestation is usually between six and eight weeks, with cubs born anywhere from mid-January to mid-March with the bulk occurring in early February (sometimes a little later as you go further north in the UK). Cubs born as early as December or as late as March are very rare exceptions. Unlike other mammals, the gestation period can vary if female badgers slow down or speed up their metabolism during their pregnancy.

Breeding Proportions

Evidence from a large badger study by Oxford University has suggested that more than 90% of adult females are mated with each year. However, only about two-thirds of them actually progress to the gestation phase. Some of these are lost, so that only about one-third of sows actually give birth each year. A proportion of cubs die underground before they are mobile; so that perhaps only about one-fifth of female badgers produce healthy cubs which survive to weaning.

Importantly, in many clans only one female produces healthy cubs each year; although this can occasionally be two sows in beneficial conditions.

Effects on Badger Society Health

The effect of this somewhat complex method is that the female badger has more of a choice of which high-quality male(s) she can mate with, and that the date of the mating is no longer relevant to when the cubs are born. It is obviously better to have cubs born with well-fed healthy mothers so that they start being weaned when food supplies are becoming much more abundant.

When many people here about the winter torpor, they often think of it as something of a lazy time for badgers when nothing of any significance is hapnning. The truth may well be that this "quiet time" allows for sows to remain undisturbed so they can live off their fat, allowing the blastocysts to implant in the womb and gestation begin in earnest.

There is some evidence that setts which are disturbed produce fewer cubs than undisturbed ones.

Cubs

New-born badger cubs are covered in grey silky hairs and usually the dark facial stripes are already visible. New cubs are about 12cm long (plus a 3-4cm tail), weigh about 75-130g and their eyes are closed for about 5 weeks. Badger cubs are fed on their mothers milk, and often live within a special nursery chamber within the sett. Their waste products are removed from the nesting chamber by the sow, until such time as they are mobile enough to use the latrines outside the sett.

Weaning usually begins when the cubs are at least three months old. During this time they feed on some solid food, particularly earthworms, and follow the mother when she goes off to feed herself.

Sense of smell is the most important sense for badger cubs, since the first two months or more of their lives are spent in darkness below ground where smell, hearing and touch are far more useful than sight. Even at three months old, the cubs are still very short-sighted. By following the example of their parents they also learn to use the "latrines" sited near the sett.

Dry, clean bedding is of great importance for the survival of the cubs. A chamber full of hay, straw and bracken acts as an efficient heat insulator, helping the cubs conserve their body heat. The straw will prevent the cubs being too battered by cold draughts; and it will insulate their bodies from the cold soil underneath where they lie down.

Academic Note:

Journal of Zoology Journal of Zoology Volume 218 Issue 4, Pages 587 - 595

Social structure of the Eurasian badger (Meles meles): genetic evidence

P. G. H. EVANS 1 , D. W. MACDONALD 1 C. L. CHEESEMAN 2
1 Department of Zoology, Oxford University, South Parks Road, Oxford OX1 3PS
2 Ministry of Agriculture, Fisheries and Food, Worplesdon Laboratory, Guildford, Surrey GU3 3LQ

ABSTRACT

Studies of territorial, highly stable groups of wild Eurasian badger, Meles meles, revealed that more than one adult of each sex may breed within a group, and that extra-territorial movements may occur within clusters of territories. Although there is some genetic structuring within a local population and a deficiency of heterozygotes, due probably to minimal juvenile dispersal, heterogeneity of gene frequencies is reduced by: (a) adults transferring between adjacent groups, and (b) matings between males of one group and females of another. Marked changes in gene frequencies between generations indicate that a minority of males have a strong influence on the genotypes of the offspring, being either polygynous or promiscuous. Within one generation, the young of a given group may be sired by two or more males, and these males may not necessarily be members of that group.

Academic Note:

Journal of Zoology Volume 242 Issue 4, Pages 705 - 728 - Accepted 30 September 1996

The demography of a high-density badger (Meles meles) population in the west of England

L. M. Rogers 1 , C. L. Cheeseman 1 , P. J. Mallinson 1 and R. Clifton-Hadley 2 1 Central Science Laboratory, Ministry of Agriculture, Fisheries and Food, Sand Hutton, York, YO4 1LW 2 Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, KT15 3NB

Copyright 1997 The Zoological Society of London ABSTRACT

Data from the longest running capture-mark-recapture study of Eurasian badgers, in an undisturbed wild population at Woodchester Park in Gloucestershire, were used to investigate population dynamics. Twenty-one social groups of badgers occupying an area of 7.3km2 were studied from 1978-1993. The density increased steadily over the study period, reaching the highest published density known anywhere at 25.3 adults per km2 in 1993, and the average social group size increased to 8.8 adults (S.E. ± 0.85) in 1993. By 1993, 97% of the population trapped was of known age and overall the population consisted of 27% cubs and 73% adults. In addition, the results supported previous studies in that the population had an equal sex ratio as cubs, but became increasingly female biased with age. There was high juvenile mortality, nearly 50% dying in their first year. Between 58 and 90.2% of adult females did not breed each year.

Academic Note:
Journal of Reproduction and Fertility (1978) 52 55-58
Plasma progesterone levels during delayed implantation in the European badger (Meles meles)
M. Bonnin, R. Canivenc and Cl. Ribes showed that there was a biphasic pattern of progesterone secretion during the year. Delayed implantation was characterized by low concentrations from February to June, a significant increase during July, August and September, and a return to low levels in October–November. A second significant increase was observed in December and early January just before the presumed time of implantation.

Michael Clark book
This is a superb
book about badgers by
Michael
Clark.
His immense knowledge of badgers really shines through.
We really recommend this book. Click here to buy: 2017 edition
2010 edition
Badger Encounters in the Wild book
Badger Encounters in the Wild Jim Crumley [Book]Superb book which describes Jim Crumley's amazing encounters with badgers in the wilds of Scotland. The quality of the writing is superb.
Click here to buy:
Encounters in the wild
Badgered to Death
Dom Dyer's polemic on the toxic mix of farming, lobbying and politics and how fake-
science, lead to badger culls in  England. Click here to buy:
Paperback edition
Kindle edition
RSPB Spotlight on Badgers book
James Lowen explores the lives of badgers and their communal living, feeding habits, and major threats to their conservation.
Click here to buy:
Paperback edition
Kindle edition
The Fate of the Badger
Dr Richard Meyer examines the evidence on which the badger-killing programme has been based. He does so in an objective manner, defending the badger and the interests of farmers.
Click here to buy:
Fate of The Badger
A Badger's Year dvd
A Badger's Year DVDThe most complete video and audio record ever made of the life of a family of wild badgers. Rarely seen, but an amazing story!
Click here to buy:
A Badger's Year DVD
George E Pearce book
Badger Behaviour, Conservation and Rehabilitation: 70 Years of Getting to Know BadgersAmazing insight into the secret world of the badger. George was one of the UK best known badger consultants, so this is a great read.
Click here to buy:
Kindle edition
Paperback edition
Hardback edition
Badger by Tim Roper
Collins New Naturalist Library (114) - BadgerThis badger reference includes tons of detail about the badger - and is good for studious audiences. There is no better book in print.
Click here to buy:
Paperback edition
Hardback edition
Kindle edition
Perfect Badger Photos
The very best photos you have ever seen of badgers are in this remarkable book by John Darbyshire and Laurie Campbell. Perfect photos and great writing. Click here to buy:
Badgers by Darbyshire & Campbell