Category Archives: The Cull

Defra (2011)

According to a meeting held between numerous scientific experts at the Department of Environment, Food, & Rural Affairs (Defra), in order for a badger cull to be effective:

  • Cull rate needs be at least 70%
  • Occurs for min. 4 years
  • Encompasses min. 150 square km

Predicted net benefit after a decade?

  • 16% decrease in bTB on average

However, is this net benefit enough to be able to control bTB? There are conflicting opinions among the public. Farmers from the National Farmers’ Union support the cull and argue this reduction in bTB is enough, whereas animal rights activists such as from the Badger Trust cite badger culling as ineffective.

Perturbation Effect

One reason that badger culling is thought to be ineffective is due to the perturbation effect, which results in surrounding areas outside of the culled region to have higher incidences of bTB infection.

This diagram below shows how the perturbation effect works:

Randomised Badger Culling Trials (1998-2007)

What is it?

  • Trial badger cull conducted by Independent Scientific Group on Cattle TB (ISG)
  • Assessed effectiveness of different types of culling for bTB control using the following experimental conditions:
Different experimental conditions

Major Findings?

  • Perturbation effect with proactive culling
    • Areas outside cull resulted in more bTB infections due to increased movements of badgers to escape cull, resulting in spread of disease
    • Decreased bTB inside culled area
  • Reactive culling not effective, increasing bTB by 29% (McDonald, 2014)
Effect of proactive culling during and after trial shows no overall benefit to badger culling for bTB control in cattle (Jenkins et al., 2010)


  • Culling = short term benefits in culled area, but ineffective in long term
  • Need to cull over large areas of land with natural boundaries to prevent perturbation effect
  • More efforts should be put into research instead

Impact on Government in 2008?

  • Creation of new advisory group
  • Decision not to proceed with further culls as effectiveness called into question

Krebs Report (1997)

Krebs Report

What is it?

  • Review of available information regarding bTB in cattle and potential transmission from badgers

Major findings:

  • Found correlative link between badger and cattle bTB infection
  • However, causative role unknown
  • Badger-to-cattle transmission risk still unquantified


  • Trial cull to assess impact of badgers on cattle bTB infection and to test effectiveness of badger cull

Impact on government?

  • Development of Five Point Plan focusing on:
    • Public health safety
    • Testing cattle for bTB
    • Vaccine Development
    • Research into spread of disease
    • Initial trial cull


The Krebs Report can be found here. (WARNING: It is extremely long!!)

How are Badgers Culled?

While culling in trials has been done in the past by live cage-trapping, then shooting, current government regulations now allow free shooting instead. With this policy, farmers are allowed to shoot badgers on sight. However this method of culling may result in maiming and a slow, painful death, and may also leave behind numerous orphaned badger cubs. Thus, free shooting has been called into question in terms of welfare for the badgers culled.

The Cull


What is the current situation?

  • Rapid outbreak of bovine tuberculosis in cattle in Great Britain
  • 14.3% cattle infected in Southwest Britain
  • 6.4% cattle infected on average for rest of country
  • All bTB-positive cows MUST be culled (euthanized for disease eradication)
    • Due to potential risk to humans
    • To prevent infectious spread to other cattle
  • Major losses to producers that need to cull livestock herds
  • Taxpayers -> $$
  • British government implements policies to cull badgers

Why cull badgers?

  • Badgers deemed significant wildlife vector for bTB transmission to cattle

Why is it so controversial?

  • Badgers not only bTB source
  • Scientific reports question effectiveness of current badger culls to stamp out bTB
  • Negative welfare implications to badgers from method of cull


Read on to find out more about badger culling in the UK…

Rationale Against Cull

Why shouldn’t badgers be culled?

  • Scientific reports show no clear evidence that badger culls would be effective in controlling bTB in cattle
    • Unless carried out over large areas due to perturbation effect
  • May result in animal welfare problems if badger not shot cleanly
    • Could maim, cause immense suffering in badgers
  • Negative ecosystem effects
    • Exact badger population numbers unknown
    • Could result in local extinction of badgers in Great Britain
    • Impact on ecosystem unknown
  • Badgers not only route of transmission to cattle!
    • Many other species susceptible
    • Cattle-to-cattle transmission accounts for greatest source of bTB infection
  • bTB risk to humans is very low
  • Issues of public safety from free shooting

Rationale For Cull

Why should badgers be culled?

  • Rising infection rates of bTB in cattle in Britain may be correlated with lack of badger population control
  • Badger culling in Ireland effective (Kao, 2012)
  • Acoording to Defra (Department of Environment, Food & Rural Affairs):
    • To protect public health
    • To enhance animal welfare and health
    • To meet European Union’s food safety regulations
    • To decrease costs to farmers and taxpayers