Call for new standards for rat, mice and mole traps

Dr Baker was speaking at the International Conference on Urban Pests (ICUP) 2017, held in Birmingham, UK
9-12 July. Her paper was presented as part of the main programme as well as at the special one-day workshop for pest control practitioners, which ran alongside the main scientific event. Pest attended the workshop presentation.

Dr Sandra Baker from Oxford University is calling for more humane rodent break-back and mole traps

This would offer a clear choice for public and professionals alike and could well lead to a cascade effect whereby leading suppliers chose to only stock ‘welfare approved’ products, thus edging out the non-approved alternatives.

Double standards go back to the 50s
Dr Baker reviewed how these double standards had come about. She explained that the anomaly goes back to the 1950s and the introduction of The Pests Act 1954, which made it an offence to use a spring trap which was not approved. On the recommendation of the UK Committee on Cruelty to Wild Animals, break-back traps for rats and mice and mole traps were exempted from this legislation.

Sixty years on, Dr Baker argued that when traps used for species of similar cognitive and emotional ability do have to be approved, such double standards seem extremely difficult to justify.

She also reminded her audience of the study into the mechanical performance of rat, mouse and mole spring traps completed five years ago by her team at Oxford (see Pest issue 24: November & December 2012). The findings from that research clearly demonstrated that there is significant scope to reduce the welfare risk associated with these traps.

Impact momentum and clamping force were measured. Relative trap performance was shown to vary significantly. Some break-back traps ‘snap’ with a force that is up to eight times weaker than others and, in some, the clamping force was up to 5.5 times weaker. There was considerable overlap between the strongest mouse trap and the weakest rat trap which, given that rats are around 20 times heavier, is particularly concerning.

Mole post-mortem study
Since this work was published, the Oxford team has also conducted a further post-mortem study of moles caught in mole traps. This concluded that the primary identifiable cause of death among moles killed in traps was acute haemorrhage and not, as would be preferred from a welfare point of view, a quick kill caused by damage to the skull or upper cervical vertebrae.

The loss of strychnine means that trapping is now the preferred method of mole control and, with rodenticide stewardship encouraging pest professionals to consider other options such as trapping, before reaching for the rodenticide bucket, it seems likely that the use for break-back traps for rats and mice will also be rising.

However, despite all the evidence Dr Baker explained that there is no appetite to change the legislation. It is for this reason that she is calling for the voluntary approach.

Which traps are the most humane?
Most professional pest managers are looking for a break back or mole trap that delivers a quick, clean kill so Iain Turner from the National Pest Technicians Association (NPTA) asked the obvious question: “Tell us which brands performed the best then we can choose the most humane traps.”

Unfortunately Dr Baker was unable to let us into that secret. All she could say was that the best break-back traps from a welfare point of view were those with larger opening angles and ‘double-peg’ spring mechanisms.

A further and very valid comment from the workshop audience came from Killgerm’s Rupert Broome who pointed out that there is already a major problem of cheap, imported break-back traps, manufactured to look identical to quality branded traps, coming onto the market. Such a voluntary system of approval would do nothing to tackle this problem. Those involved would simple re-create any approval logos or certification marks.

It’s an important point but, surely it would be a step in the right direction to at least know which of the branded traps offer the best kill and the voluntary approval system proposed would deliver that. The second step would then be to make sure you purchase your branded trap from a reputable supplier such as Killgerm.

New BPCA code in production
The British Pest Control Association (BPCA) is currently producing a Code of Practice for break-back traps. We understand this will be available in October this year. Watch this space!