By Henrietta Appleton, GWCT Policy Officer (England)
The GWCT supports the return of native species including by reintroduction – after all we have been party to some of them! However, we are of the view that all reintroductions must follow International Union of Conservation of Nature (IUCN) Guidelines. We therefore support the recent firm line taken by Therese Coffey in her speech to the NFU Conference that Lynx and Wolf reintroductions are not needed. These species are only part of a ‘conservation’ approach that generates more questions than answers.
The IUCN Guidelines for reintroductions and other conservation translocations
Reintroductions are just one aspect of the conservation spectrum and are designed to return species or to improve their status within their indigenous range. If there is a remnant population then the technical term is reinforcement; if not then it is correctly termed a reintroduction. If the translocation is outside the indigenous range then correctly it is either an assisted colonisation (if the aim of the release is to avoid population extinction at any scale) and/or ecological replacement (where the ecological function has been lost due to extinction of a similar species).
These terms are taken from the IUCN Guidelines for Reintroductions and Other Conservation Translocations from 2013. The forerunner of these were produced in 1995 when the IUCN sought to impose some order into a conservation approach that was gathering momentum. These guidelines (and those produced by Defra) are important and, for the GWCT, a vital aspect of species reintroductions. Our concern with some of the reintroduction programmes in the UK is that these guidelines are not properly adhered to.
The reintroductions that make the headlines tend to be of mammals or birds such as beavers and red kites and often there is a strong public engagement element to the project. But there are also important projects that seek to reintroduce species lower down the ‘food chain’ – such as hoverflies – and those that involve a species that is a necessary part of the restoration of an ecosystem (the ‘ecological replacement’ mentioned above) e.g. wetland plants such as sphagnum mosses and bog asphodel which have been reintroduced as part of the Great Manchester Wetlands Project by Lancashire Wildlife Trust and others. Incidentally their website specifically mentions that they are following the strict IUCN protocol.
Whilst an ‘ecological replacement’ is arguably justified, some of the reintroductions proposed may well undermine the conservation of our existing indigenous wildlife. This becomes a matter of weighing-up priorities and requires policy to link reintroductions to existing conservation objectives and targets (such as those in the Environment Act).
For example, surely we should be focussing our efforts on conserving the remnant populations of some of our red-listed species such as Curlew and Lapwing, rather than reintroducing European Wildcat and Pine Martens to areas in the south of England where these ground-nesting waders are fast-declining in part due to high predation pressure from common predators like foxes (which can be controlled).
This seemingly contradictory outcome should be part of the project’s pre-release assessment and evaluation as well as considered in the formulation of an exit strategy and the on-going monitoring post release – IF the IUCN guidelines on reintroductions are faithfully followed. However, this is not always straightforward. Take the Pine Marten for example.
The Pine Marten Reintroduction Programme and its impact on other species
Pine martens are listed under Schedule 5 of the Wildlife & Countryside Act 1981. This protected status creates consequences for other legal trapping practices undertaken for conservation and pest control purposes such as the control of rats, grey squirrels and other mustelids in spring traps.
The tunnels in which these traps are typically set include 50mm square or core-drilled external excluders and internal baffles to minimise risk of non-target captures; yet adult pine martens are known to be able to squeeze through a 45mm gap, and juveniles will pass through smaller gaps still. So, in areas where release is targeted, tunnel trap users would need to alter excluder configurations accordingly.
But research by the GWCT has shown that the size of physical excluders used to prevent access by adult pine martens and polecats also reduces captures of grey squirrels and rats. In addition, the risk of accidental capture of pine martens in these traps lawfully set for grey squirrels and other mammalian pest species is a concern as what constitutes a ‘reckless act’ is not yet clear.
Consequently allowing further Pine Marten reintroductions in the absence of Defra-endorsed guidance for such situations could have consequences for the conservation of a wide range of at-risk species that benefit from the deployment of traps for game and wildlife management or woodland protection purposes by burdening wildlife managers with an added layer of risk management and legal uncertainty. What is also clear is that existing pine marten re-introductions have not addressed these elements sufficiently, and consequently no strategies for effective mitigation have yet been tested.
In addition, we note that some projects are using untested (at least in the UK) global models such as the Conservation Standards model with no reference to Defra’s guidelines – let alone the IUCN. The conservation standards model appears to be based on how stakeholder cooperation can achieve a desirable outcome rather than scientific assessment and evaluation and so clearly plays to the public interest agenda.
The GWCT's experience with reintroduction programmes
Many GWCT members reading this will know that we have been involved in grey partridge recovery projects involving reinforcement, water vole reintroductions and black grouse translocation to increase their range to mention just a few. In each case we followed IUCN guidelines and undertook post-release monitoring.
We are also looking to add to this list through a hedgehog project at Allerton which involves combining the implementation of IUCN Guidelines and community engagement. However, there is opposition to us moving hedgehogs from other sites. This presents a conundrum – do you rehabilitate hedgehogs and return them to where they were found injured or in poor health or do you move them to pristine habitat away from busy roads? Which is likely to optimise survival and breeding success?
My final point is that where reintroductions are successful, natural dispersal through appropriate habitat provision may be all that is required to return a native species to a previously occupied area - and not further reintroductions. Some species naturally disperse considerable distances; one reason for the need for continued monitoring as this may cause an impact well away from the original release site.
For example, of 39 pine marten released in Wales in 2015 and 2016, four undertook long-distance dispersal – one over 100km from the release location! This is an extreme case (the mean was 14km) but it indicates that for some species where there is a likely conservation conflict with other red-listed species (as identified above), natural dispersal should be regarded as sufficient. Free-living pine marten populations exist in Shropshire, Northumberland (likely due to dispersal from Southern Scotland) and the New Forest, with occasional sightings in the Lake District and the North York Moors.
So whilst we welcome Therese Coffey’s assertion that Lynx and Wolf will not be reintroduced, we remain concerned about the lack of oversight of existing projects and their adherence to IUCN and Defra guidelines (even those led by Government arm’s length bodies). The potential that some have to undermine existing conservation ambitions to restore the remaining populations of red-listed species and thereby achieve biodiversity targets, is very concerning.