How many badgers do culls really kill?

Yesterday I learned that the organisation Wild Justice is mounting a legal challenge to England’s badger cull, based on the argument that it is inhumane to badgers. I have tended to steer away from the issue of humaneness, because I am not an expert on animal welfare. When the current culling approach was piloted in 2013, actual welfare experts on the Independent Expert Panel concluded that free shooting failed to meet the criteria it had set for humaneness (because more than 5% of badgers were estimated to take more than 5 minutes to die). When subsequent culls failed to improve welfare standards, the British Veterinary Association called for an end to the practice of free shooting badgers, on welfare grounds. I don’t know the details of the Wild Justice case, but concerns about the welfare of culled badgers are definitely legitimate.

The news from Wild Justice got me thinking about the badgers which are wounded by free shooting. Every year since the culls started, Defra has published a measure first calculated for the Independent Expert Panel – the proportion of badgers which are shot at but not retrieved. Some of these badgers may be missed, some will be badly injured, and retrieval of carcasses by activists show that at least some crawl off and die where marksmen never find them. The Independent Expert Panel supplemented this measure with other measures of welfare, all of which pointed to the same conclusion – that an unacceptable proportion of badgers targeted by free shooting suffer seriously before they die. But this measure is the simplest and, as it’s the only one that Defra has continued to record, it has become the basis for Natural England’s annual evaluations of the humaneness of controlled shooting.It occurred to me that the published figures on this proportion of badgers shot at but not retrieved (which I’ll call PN), and the number of badgers shot and retrieved (which I’ll call NR), would allow me to estimate the total number of badgers shot and NOT retrieved (which I’ll call NN). (The formula is NN = (PN*NR)/(1-PN) if you want to check my workings). This failure to retrieve badgers only applies to those targeted by free shooting, not those killed in cage traps.

My calculations are shown in the table below – hyperlinks give the source of each figure quoted. Each year about 11% of the badgers that were shot at were not retrieved, with no change over time (yes the published figures for 2014 and 2015 really are identical). The numbers of shooting events monitored each year are not high, and so the confidence intervals (which you can calculate here if you want to recreate the analyses) are quite wide. But if you consider all seven years of monitoring together, the confidence interval narrows to 8.5-13.5%. These figures suggest that, over seven years of culling, between 6,036 and 10,118 badgers have been potentially wounded by free shooting but not retrieved.

Year:2013201420152016201720182019Total
Badgers reported killed        
total reported killed (NR+NT)1,8796151,46710,88619,53732,60135,034102,019
number reported killed by free shooting (NR)1,0493137435,66611,83420,63724,64564,887
Natural England observations of shooting accuracy    
shooting events observed8863631127489149638
badgers not retrieved106612991769
proportion not retrieved (PN)0.11360.09520.09520.10710.12160.10110.11410.1082
lower exact binomial confidence limit0.05590.03580.03580.05660.05710.04730.06790.0851
upper exact binomial confidence limit0.19910.19590.19590.17970.21840.18330.17640.1349
Extrapolation to annual number shot but not retrieved      
estimated number shot but not retrieved (NN)13433786801,6392,3223,1747,869
lower estimate unretrieved6212283407171,0251,7956,036
upper estimate unretrieved261761811,2413,3074,6325,27910,118
Estimated total badgers killed        
Estimated total killed (NR+NT+NN)2,0136481,54511,56621,17634,92338,208109,888
lower estimate killed1,9416271,49511,22620,25433,62636,829108,055
upper estimate killed2,1406911,64812,12722,84437,23340,313112,137

This is a lot of badgers suffering, which is cause for concern, especially when there are other TB control methodswhich are more humane, as well as being cheaper, less environmentally damaging, and more likely to contribute to TB eradication.

These “lost” badgers aren’t counted in the cull totals reported. Including them takes the number of badgers killed since the policy started from 102,019 to somewhere between 108,055 and 112,137. Repeating the calculations for individual culls suggests that these additional “lost” badgers were numerous enough for five culls (of 107 for which data were available) to exceed their maximum targets and thus potentially break their licence conditions (these were the 2016 cull in Area 6-Devon, the 2017 cull in Area 17-Somerset, the 2018 cull in Area 3-Dorset, and the 2019 culls in Areas 4-Cornwall and 36-Staffordshire). The calculation of these minimum and maximum targets is fairly arbitrary, so exceeding the maximum target does not necessarily mean that the badger population is at risk of extinction. Nevertheless, these targets are part of Natural England’s statutory licensing process, and the data which show that they may have been exceeded also come from Natural England. The fact that these datasets have not been brought together previously suggests that Natural England’s humaneness monitoring may represent more “going through the motions” than a serious concern for badger welfare. Contrast this with the Randomised Badger Culling Trial, in which evidence of trap-related injuries was used to improve trap design and hence badger welfare.

I hold three licenses to vaccinate badgers and conduct research on them, and all of these rightly require close attention to badger welfare. These licences cannot be directly compared with cull licences, because the animals are kept alive and released back to the wild so, could be suffering for a long time if my team were to injure them. Nevertheless, I wonder whether the requirements for things like timing of trap checking, dealing with bad weather, and so forth, are the same for cull licences as they are for vaccination and research licences? Perhaps Wild Justice will be checking? 

2 thoughts on “How many badgers do culls really kill?

  1. I remember some terrible weather in 2013 during the Somerset cull when Natural England did not call a halt to caging and some badgers were found close to water in flooded cages. I heard a part of a monitors report concerning a badger who took longer than 5 minutes to die while they were getting to it, it was pitiful and so distressing to listen to. I don’t know where the hearts of these people lie. In money and power I suspect because no one could allow this suffering against a clear and consistent backdrop of such cataclysmic failure.

Leave a Reply

Your email address will not be published. Required fields are marked *