A range of environmental concerns have been raised about land intensively managed for driven grouse shooting and RSPB is calling for a licensing system to promote accountability and good practice. A recent incident has also highlighted concerns about the use of spring traps for predator control.

On 12 July this year, a fell runner was out on a large driven grouse moor in Northumberland when he came across this trap containing a crushed merlin. These traps are commonly referred to as a rail or bridge trap. They typically consists of a log or pole across a small burn on which a spring trap is set and covered with a mesh cage. These traps are routinely used to kill rats, stoats and weasels. However, the images he took and sent to us (along with a precise ten figure grid reference - very helpful, thank you!) painted an unpleasantly graphic picture of the problems that rail traps can bring.

A juvenile male merlin killed in an illegally set spring trap on a Northumbrian grouse moor

This image of a dead juvenile male merlin firmly clamped in the jaws of the trap drew the attention of everybody in our office. What was abundantly clear was that there was no restriction at either end of the mesh cage to exclude any non-target animals. By chance I was due to visit a friend that evening in Northumberland, so decided I could visit the site the following morning. Coincidentally, as I cycled into Bedford to collect my hire car I came across a family of three stoats on the cycle path. I came to a halt and stood mesmerised as they bounced around like only stoats can and came within a few metres of me. It is understandable that the use of spring traps, whilst lawful, to kill such enigmatic animals on grouse moors is unacceptable to many.

Location of the merlin caught in the rail trap


The following morning I walked across a large area of intensively managed grouse moor and recovered the pitiful body of the merlin. The measurements taken show an unrestricted cage tunnel around 20cm wide and 15 cm high.

Both ends of the mesh cage covering the spring trap had unrestricted access

Going downstream I found another set rail trap, but in contrast this had two nails used to impose some access restriction. The merlin was sent off for a post mortem examination, and whilst there were signs of internal bleeding, it was not possible to assess just how quickly the bird died after being caught. Hopefully the end was quick.

I reported the matter to Northumbria Police, and the Wildlife Crime Officer allocated to the case quickly arranged to visit the site with my colleague Howard to recover the trap. There was an intention to consider testing the trap for human DNA but fortuitously the trap operator, an experienced gamekeeper, was met nearby and accompanied them to the site. The rail trap had now been reset and a further rail trap upstream had access restriction in place, again highlighting the obvious deficiency with the trap which had killed the merlin. The gamekeeper was formally interviewed a few days later and accepted responsibility for the rail trap stating he had been running it for a few months and that his failure to restrict access was a mistake.

The police elected to deal with this by way of adult caution. Many people will be aware of the furore in 2016 when North Yorkshire Police mistakenly cautioned a young gamekeeper for setting three pole traps. This case is clearly less serious, with no intention to trap a bird of prey, however this rail trap had been set by an experienced gamekeeper in grossly negligent manner with obvious and serious risks to non-target wildlife. The police gravity matrix for wildlife offences does allow adult cautions for first offences. However, we felt there were some significant aggravating factors that justified this matter going to court and wrote to Northumbria Police about this decision. In fairness, an Inspector has promptly reviewed the matter, sought further guidance, and clearly set out their reasoning why they took this course of action. Whilst we may ultimately agree to differ on the final disposal of the case, we are grateful for the work of the officers involved.

Rail traps – fit for purpose?

Whilst the trap which killed this merlin had clearly been set in an unlawful manner, I feel there are some significant questions that need to be answered in relation to rail traps in general. There seems no doubt there has been an explosion of the use of rail traps on grouse moors in the last ten years or so and it is a very commonly used method to target small mammals. Many have insufficient access restriction with birds as large as red grouse being caught. Even when set with 'acceptable' access restriction – there appears to be a regular reported bycatch of birds – a range of terrestrial species includes thrushes, wagtails, dippers, starlings, skylarks have all been reported as caught and killed in such traps. We have received numerous photographs and many others have appeared on social media.

Red grouse, pied wagtail, ring ouzel and song thrush are some of the species which have been killed by rail traps

The effectively transparent nature of the mesh cage covering the spring trap means that birds are simply hopping or walking along the log or pole on which it is set. It appears a 2 by 4 inch hole in some covering mesh (or in some cases a couple of six inch nails) is presenting little real deterrent for birds up to the size of a thrush. Of particular concern to me are ring ouzels, a declining red-listed bird with a population range of 6,200 to 7,500 pairs and in significant decline over the last 40 years. We have had several reports of ring ouzels killed in these traps, including one this month about a bird killed in the Peak District. I once had to shoo one away which looked like it was about to hop through a rail trap tunnel. Disturbingly, I was told on one grouse moor in the north of England they were annually catching 4-5 a year as bycatch. In view of the fragile conservation status of this species, any additional mortality of this nature, particularly if adult birds, raises concern whether rail traps could potentially have a negative conservation impact.

Several ring ouzels have been confirmed as killed in rail traps

What the law says

The current law says two interesting things. That where a spring trap is approved for use against a particular mammal species then
1. ‘so far as is practicable without unreasonably compromising its use for killing or taking target species, the trap must be used in a manner that minimises the likelihood of its killing, taking or injuring non-target species’.
2. Furthermore for the spring traps commonly used for rail traps that ‘The trap must be set in a natural or artificial tunnel which is, in either case, suitable for the purpose’.

In relation to the first part, there is a question whether this is in conflict with Section 11 Wildlife and Countryside Act 1981 which states that it is an offence ‘if any person sets in position any of the following articles, being an article which is of such a nature and so placed as to be calculated (Scotland uses term ‘likely’) to cause bodily injury to any wild animal included in Schedule 6 which comes into contact therewith’.

Schedule 6 includes red squirrels, polecats and pine martins which could be all be vulnerable to rail traps, particularly those with sub-standard access restrictions. There are similar potential conflicts with the illegal trapping of birds under Section 5 of the Act.  So how does not ‘unreasonably compromising’ the capture of a stoat fit with being a trap being 'likely' to catch a polecat,a red squirrel or a bird? I am not aware of any binding legal decisions, but the potential for confusion is clear and probably not helpful for legitimate trap users or the courts.

In relation to the second part, in writing this blog I did a bit of further research as I was aware that under the Agreement on International Humane Trapping Standards (AIHTS) significant changes are in the pipeline relating to stoats. I spoke with a couple of very helpful people at GWCT and Defra about the complexities of these changes. Following long delays, a Defra consultation took place in March this year with results announced in July. New spring traps to kill stoats more humanely will be required in the future, though there are delays in implementation. The new traps for stoats will probably cost about twice as much, whilst the ones currently in use will still be legal for weasels and rats – so what do we think will happen with rail traps? Will they be upgraded to the new spring traps or will some simply say they are not targeting stoats and that any stoats caught are now non-target by-catch? The opportunities for mischief and poor practice could be considerable. It will be fascinating to see how the industry responds.

In 2020 more humane spring traps will be legally required to kill stoats

Whilst approved traps have to be tested, strangely there appears to be no prescribed or recommended access sizes for different target mammals. More worryingly, there appears to be no agreed standard of what is an ‘acceptable’ level of non-target by-catch for any particular trap. So if for every 100 target animals killed, one non-target bird or animal was caught – then I expect some people might accept that was a sufficiently low level. But what if it was 5, 10, 15 or even higher? As far as I can see, nobody actually knows what the level of non-target by-catch even with ‘properly restricted’ rail traps. There appears to have been no studies to check the efficacy of these traps, and no monitoring program on the actual level of by-catch. So who actually has the data to say that the artificial tunnels used for rail traps actually comply with the law and are ‘suitable for the purpose’ and ‘minimise the likelihood of killing, taking or injuring non-target species’. I think there is a fair question as to whether rail traps are legally fit for purpose.

I have no doubt the photographs of birds caught in rail traps will keep coming in. Gamekeepers and other rail trap users must be seeing these problems first hand far more often than members of the public. When you consider the size of the shooting industry and the resources available to it – then one wonders why proper research hasn’t already been done on this issue?

In the meantime, I would encourage anyone who comes across these rail traps, not to interfere if they appear reasonably set, but if the access restriction seems insufficient then take photographs (with something for scale), accurately record the location and report this to the police on 101. Please let the RSPB know about any rail traps with caught birds – again good photos, and the size of the access point are invaluable.

More eyes and ears on this matter will hopefully lead to more accountability and help promote better practice leading to far less of these unwanted images.