This is the “badgers moving the goalposts” argument, which repeatedly comes back to haunt this debate. The important thing is to have accurate numbers, not least because we do not want to break the Bern convention, and therefore the law, in terms of taking the risk of eradicating an entire species.
On four occasions, the RBCT conducted non-simultaneous culls—this comes back to the point about the short period of time, as they went on over a prolonged period. It was found—the evidence is there—that there was an increase in the proportion of badgers infected, over and above the background norm of the increase in numbers infected by the proactive culling.
In 2010, DEFRA’s science advisory council said:
“There is little useful data on the issue of what time period should be considered as ‘simultaneous’. The Group advised that if culling was carried out in a period of up to 6 weeks (although preferably less), that is likely to reduce the adverse effects of non-simultaneous culling; this advice is based on opinion and not on evidence. The longer the period that culling is carried out in, the less confident one can be that the deleterious effects seen with non-simultaneous culling as carried out in the RBCT will be minimized.”
That is from DEFRA’s own science advisory council. It is absolutely clear that the pilot culls took a fairly significant risk in planning to meet the six-week target. The fact that they failed comprehensively to meet that target supports the claim in the independent expert panel report that the pilot culls were ineffective; they took 63 and 77 nights respectively. Remember that the randomised badger culling trial found that to maximise impact, a cull should take place over eight to 11 nights.