It is the OV’s role to relay focused information to farmers on how best to protect their cattle from bovine TB. In the high-risk areas of Great Britain, badgers are recognised as a reservoir of bTB infection. It is important that OVs understand bTB biosecurity and are confident in explaining the current government policy to farm clients.
Measures can be taken to minimise interaction between badgers and cattle and in turn reduce the risk of transmission (through direct or indirect contact). But how do you spot signs of badger activity, and what biosecurity measures are recommended to reduce contact between the two species?
Ian Vernon is a field ecologist for the National Wildlife Management Centre at APHA, where he has worked for 12 years. He is involved in ecological and epidemiological studies of badgers and bTB infection, and he was a key speaker at the TB Farm Advice Workshops run by Improve International. Ian shared his expertise and advice with me.
Do badgers visit the farm buildings?
One way to determine whether badgers visit a farm building is to take a walk around the site and look for signs of badger presence.
OVs should consider what is in the building that badgers might be interested in: is there food, water, bedding or somewhere that could be used as harbourage? If the building is home to any of these resources, OVs should look for signs of badgers entering. Typically, badgers use the same entrance point and pathway, leaving visible signs around the perimeter. To accurately identify badger activity, you must familiarise yourself with these signs.
Footprints
Finding footprints is the best way to identify badger presence around farm buildings. They are simple signs to spot and to identify as belonging to a badger. The badger footprint is unique among British mammals: it is shaped like an oval pad with four toes spread neatly across the top. Occasionally, the fifth toe and claw marks will also be visible. Fox and dog footprints, by contrast, typically have diamond-shaped pads with toes more arced around the pads (two forward and two back).
Are there hotspots of activity around the farm land?
When looking more widely around the farm land, setts, runs and latrines tend to be the most obvious signs of badger activity. Tufts of hair on fences and claw marks on water troughs may also be useful for identifying badger presence in specific areas of the farm.
Setts
Badgers usually have one main sett and numerous outlying setts of varying sizes around the territory. Typically, there will be a lot of activity around the main sett over winter and spring. In summer and autumn, smaller, more remote setts become sites of increased activity.
Badger setts typically:
- Are dug in well-drained soil in banks and areas with some cover
- Have an entrance resembling a rotated capital ‘D’ – the bottom of the tunnel is usually flat; they’re wider than they are tall and have an arced top
- Have a deep channel that develops as the digging badgers pull soil with them from the sett
- Have a large spoil heap of soil that the badger has kicked out
- Remain wide (in contrast to rabbit holes, which tend to narrow to a smaller hole)
Active badger setts typically:
- Are free from debris
- Have disturbance near the entrance and sometimes footprints in the soil
- Have signs, or even pathways, of bedding materials, like grass and straw around the entrance
Runs
Runs are visible pathways that tend to emanate from hedgerows and often lead from one plot of land to another. They are usually visible as flattened grass or muddy trails and can be paired with other evidence such as latrines, regular access points to and from setts, or snagged badger hair on barbed wire.
Faeces and latrines
Badger latrines are quite distinctive. They are almost always in dug pits, which act as territorial marking areas so are likely to be reused.
If in pasture, the latrines are often located on a run or against a linear boundary, such as a hedgerow. Latrine activity increases when badgers emerge in spring to re-establish their territories on social-group boundaries, and in autumn to reinforce territories.
Hair
Guard hairs – the outer hairs on the top of a badger’s back – have a wavy profile along the length. Because they aren’t round, it is difficult to roll a badger guard hair between your fingers. Badger hair can be found anywhere the animal has squeezed through a gap.
Water troughs
Badgers may use water troughs. They usually find the lowest point to drink from and can leave signs such as: scratch marks (look for four parallel claw lines left by the hind-leg claws at the base of the trough), corresponding clean patches on the lip of the trough (where the badger has rubbed dirt away when leaning over to drink), and adjacent runs in hedges.
How to minimise contact between badgers and cattle
If badgers have been identified on a farm, it is advised that measures be introduced to minimise badger-cattle interaction. Which measures are recommended will depend on where the hotspots of badger activity are located on site.
Temporary fences in pasture
If signs of regular badger activity are found around pasture, temporary fencing is usually recommended.
Sett entrances should not be fenced off, but fencing can be erected around larger areas of regular activity (for example, areas with latrines or sett holes emerging on to pasture). The fencing should be used to keep cattle away from badgers rather than vice versa.
Barriers for farm buildings
Even if the food being stored in a feed-store building isn’t suitable, badgers can find other sources in buildings, like insects and mice. Badgers will eat grain and cattle cake, too. It’s important to note that you may not always see signs of badgers feeding – they may consume all spilled feed, leaving no reason to suspect their presence.
To prevent badgers from entering buildings, walls and gates should be at least 1.5m high and constructed from a smooth material.
It is recommended that doors are kept closed and gaps reduced. Reducing a gap to 7.5cm (horizontally or vertically) should be enough to keep badgers out.
Electric fencing (to keep badgers out this time, as opposed to fencing designed to limit cattle’s movements which is recommended for pasture) should have strands at 10cm, 15cm, 20cm and 30cm from the ground. This may act as an effective deterrent and could be useful for the backs of silage clamps; electric-fence systems can also be set up across clamp faces.
Water troughs
Though it has not been proven that bTB can be transmitted via shared water sources, measures can be taken to reduce any risk. Free-standing and raised troughs may discourage badgers but generally if a trough has been raised too high for badgers to use, it is likely to be too high for cattle as well. Farmers can empty any troughs that aren’t being used by cattle; this may break the pattern of a badger’s habit. Troughs can be moved away from setts and latrines and can be covered when not in use.
Further information and advice
For further information, farmers can be pointed in the direction of the TB Hub, where some TB biosecurity information sheets are now available.
