Abstract
Culling is often considered as a tool for controlling wildlife diseases that can also
infect people or livestock. Culling European badgers Meles meles can cause both
positive and negative effects on the incidence of bovine tuberculosis (TB) in cattle.
One factor likely to influence the outcome of different badger-culling strategies for
cattle TB is the reduction in badger population density achieved. However, this
reduction is difficult to measure because badgers, being nocturnal and fossorial,
are difficult to count. Here, we use indices of badger abundance to measure the
population impacts of two culling strategies tested in Britain. The densities of
badger setts and latrines recorded before culling were correlated with the densities
of badgers captured on initial culls, suggesting that both were indices of actual
badger abundance. Widespread ‘proactive’ culling was associated with a 73%
reduction in the density of badger latrines, a 69% reduction in the density of active
burrows and a 73% reduction in the density of road-killed badgers. This
population reduction was achieved by a coordinated effort entailing widespread
and repeated trapping over several years. However, this strategy caused only
modest reductions in cattle TB incidence in culled areas and elevated incidence in
neighbouring unculled areas. Localized ‘reactive’ culling caused a 26% reduction
in latrine density, a 32% reduction in active burrow density and a 10% reduction
in the density of road-killed badgers, but apparently increased the incidence of
cattle TB. These results indicate that the relationship between badger population
reduction and TB transmission to cattle is strongly non-linear, probably because
culling prompts changes in badger behaviour that influence transmission rates.
These findings raise serious questions about the capacity of badger culling to
contribute to the control of cattle TB in Britain.
infect people or livestock. Culling European badgers Meles meles can cause both
positive and negative effects on the incidence of bovine tuberculosis (TB) in cattle.
One factor likely to influence the outcome of different badger-culling strategies for
cattle TB is the reduction in badger population density achieved. However, this
reduction is difficult to measure because badgers, being nocturnal and fossorial,
are difficult to count. Here, we use indices of badger abundance to measure the
population impacts of two culling strategies tested in Britain. The densities of
badger setts and latrines recorded before culling were correlated with the densities
of badgers captured on initial culls, suggesting that both were indices of actual
badger abundance. Widespread ‘proactive’ culling was associated with a 73%
reduction in the density of badger latrines, a 69% reduction in the density of active
burrows and a 73% reduction in the density of road-killed badgers. This
population reduction was achieved by a coordinated effort entailing widespread
and repeated trapping over several years. However, this strategy caused only
modest reductions in cattle TB incidence in culled areas and elevated incidence in
neighbouring unculled areas. Localized ‘reactive’ culling caused a 26% reduction
in latrine density, a 32% reduction in active burrow density and a 10% reduction
in the density of road-killed badgers, but apparently increased the incidence of
cattle TB. These results indicate that the relationship between badger population
reduction and TB transmission to cattle is strongly non-linear, probably because
culling prompts changes in badger behaviour that influence transmission rates.
These findings raise serious questions about the capacity of badger culling to
contribute to the control of cattle TB in Britain.
| Original language | English |
|---|---|
| Pages (from-to) | 28-37 |
| Number of pages | 10 |
| Journal | Journal of zoology |
| DOIs | |
| Publication status | Accepted/In press - 14 May 2007 |