In August I wrote a blog following the illegal killing of a merlin in a spring trap set on a driven grouse moor in Northumberland. I also raised some wider concerns about the use of spring traps and whether they were actually legal when set as a ‘rail trap’; furthermore about possible impacts on ring ouzels, a declining 'red-listed' species, following several reports of birds being killed in these traps.

Ring ouzel killed in a rail trap in the Peak District National Park earlier this year (Kim Leyland)

Interestingly, a research colleague very recently blogged ‘Super-ouzel returns…’ There is no doubt that super-ouzel, which hatched in 2008, is a special bird. In addition to having clocked up tens of thousands of miles on migration, surviving all the other perils of the natural world, he has made at least 16 successful breeding attempts rearing an amazing 58 chicks. However, even super-ouzel would have no chance if it hopped along a log over a stream being used as a rail trap.

The study at the site in Scotland shows that survival, especially of  first-year birds, has a major influence on the ring ouzel population trend. So, any additional 'unnatural' mortality is clearly undesirable. Whether rail traps are having any impact on the overall conservation status of ring ouzels is unknown. However, we believe there are enough concerns about bycatch and the actual legality of these traps that some proper research should be undertaken. As a result, we have written to Department for Environment, Food and Rural Affairs (Defra), as set out below. I will update in due course on any response we receive.


'Enquiry to Defra - RSPB concerns re use of rail traps and non-selective capture and killing of wild birds

Dear Sir

I am writing to raise our increasing concerns in relation to the use of spring traps when configured in a manner commonly referred to as a ‘rail trap’ or ‘bridge trap’. These typically consist of a Fenn Mark IV spring trap, or equivalent, set on a log or pole across a small stream and covered with a mesh cage. These are normally found in association with land managed for driven grouse shooting. In light of the ongoing AIHTS review in relation to stoats, and the proposed Spring Traps Approval Order 2018, this seemed an appropriate time to raise our concerns.

Over the last ten years there appears to have been a significant increase in the use of rail traps, with the traps intended to kill small mammals, especially mustelids. We have received reports of illegally set rail traps (e.g. set with insufficient access restriction), and birds as large as red grouse, being caught. However, what is of more concern are the increasing reports of bird bycatch in rail traps where access restrictions are in place are which are generally considered as lawfully set. We have received reports and photographs, along with numerous others appearing on social media, of a range of terrestrial species including ring ouzels, blackbirds, song and mistle thrushes, pied wagtails, dippers, starlings, skylarks as being caught and killed in such traps.

It appears 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. The access restrictions being used, typically a 2 x 4 inch hole in the covering mesh, or in other cases just a couple of six inch nails, seems to be presenting little real obstacle for birds up to the size of a thrush. Of particular concern are ring ouzels, a red-listed bird with a population range of 6,200 to 7,500 pairs and in significant decline over the last 40 years. There is published work about the impact of poor adult and first-year bird survival in ring ouzel populations. We have had at least seven confirmed reports, backed up by photographs, of ring ouzels caught and killed in rail traps1. In at least four cases there was a fairly typical access restriction in place. We have also received anecdotal information of one upland estate apparently catching four to five ring ouzels per annum.

Regulation 2 of the draft Spring Traps Approval (England) Order 2018 is the same as the current 2012 Regulations, and includes: -
(2)(b) 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;

Within the draft SI Schedule, for the Fenn Mark IV and equivalent spring traps it continues to use the 2012 wording and states ‘The trap must be set in a natural or artificial tunnel which is, in either case, suitable for the purpose’.

Whilst the spring traps themselves are tested to ensure they are suitable for the humane dispatch of target mammals, there is no guidance on access sizes or tunnel design for different target mammals – this is currently left to the operator to decide. Whilst rail traps have been widely adopted, we are unaware of any trials or other work to test whether this type of configuration is actually ‘suitable for the purpose’. For example, has there been any monitoring program on the actual level of bycatch of rail traps? More generally, we would be interested to know if there are any guidelines on what is considered an ‘acceptable’ level of bycatch for any approved trap.

In contrast, with some of the other approved spring traps there are prescriptive conditions on the types of tunnels used, for example some must be used within a housing provided by the manufacturer. We note for the DOC traps listed within the draft SI Schedule that there is a proposed change in the conditions of use. The current 2012 SI states ‘The trap must be set in an artificial tunnel constructed to the design specified by the Department of Conservation’.

However, the draft 2018 SI now differentiates between baited and run-through configurations, and in the latter case reverts to the less prescriptive condition of ‘in a natural or artificial tunnel which is, in either case, suitable for the purpose’. Understandably, we are concerned if DOC traps are used in a run-through trap by setting them in a rail trap configuration, that there will be problems with bird bycatch for these traps as well.

In relation to the potential lack of selectivity of rail traps, we would draw attention to the Birds Directive and the Wildlife and Countryside Act 1981. Article 8(1) of Directive 2009/147/EC states: -
‘In respect of the hunting, capture or killing of birds under this Directive, Member States shall prohibit the use of all means, arrangements or methods used for the large-scale or non-selective capture or killing of birds or capable of causing the local disappearance of a species, in particular the use of those listed in Annex IV, point (a)’.

Consequently, there is a general prohibition on the non-selective capture or killing of birds. Member States may potentially derogate from the provisions of Article 8, where there is no other satisfactory solution. In this case, the obvious satisfactory solution would seem to be using spring traps in a manner which effectively eliminates or minimises bird bycatch.

Section 5(1)(a) of the Wildlife and Countryside Act 1981 (England and Wales) states: -
‘if any person sets in position any of the following articles, being an article which is of such a nature and is so placed as to be calculated to cause bodily injury to any wild bird coming into contact therewith, that is to say, any springe, trap, gin, snare, hook and line, any electrical device for killing, stunning or frightening or any poisonous, poisoned or stupefying substance;’

Section 11(2) has similar provisions for protection of animals included on Schedule 6 of the Act, and we have also received reports of red squirrels caught in rail traps. We believe other Schedule 6 species like polecats, and potentially pine martens, are also vulnerable to such traps.

The CPS have previously provided advice that ‘calculated’ effectively equates to ‘likely’ and indeed in Scotland the legislation has been amended to use the word ‘likely’ in both these sections of the Act.

In view of the bird bycatch reported to us, surely a very small percentage of that actually taking place, we believe that there is a good argument that the rail traps being widely used in their current configurations are ‘likely’ to catch wild birds and therefore potentially illegal. In the absence of any apparent information on the efficacy of rail traps, we believe there are genuine grounds for concern that these devices are simply not sufficiently selective and do not conform to the requirements of the Birds Directive.

In relation to rail traps we believe a proper assessment of their suitability needs to be made. We believe it may be appropriate for consideration to be given to developing either a bespoke tunnel housing, or perhaps prescriptive information in relation to the design of these, in line with the conditions for certain other approved spring traps. We believe this would help ensure that rail traps are selective for target mammals and properly minimise bird (and protected mammal) bycatch.

We would welcome your thoughts on these issues.'

Update  26 November 2018

Following the above blog, I received further photographs of bird bycatch in rail traps involving ring ouzels.  As a result I sent the following update to Defra.  

'Further to my email of the 5 November expressing concerns about bird bycatch in rail traps, I also produced a blog in relation to this matter.  Following this blog, I have been supplied with photographs by a very reliable observer of decomposed thrushes caught in four different rail traps on grouse moors in the North York Moors National Park during 2018. All the traps had the usual access restrictions in place. Two of the birds caught are very probably ring ouzels, and two possibly ring ouzels or another thrush species.  This further demonstrates that, even when these traps are set with what is considered acceptable access restrictions in place, they are still likely to catch non-target birds. We believe this raises further questions about whether spring traps used in this manner are actually lawful.'