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Species Reintroduction

Special species…

Species Reintroduction

Special species

Species reintroduction is one of the most complicated and controversial subjects in conservation today, but recent initiatives in Scotland – including the reintroduction of beavers – promise to alter not only the physical landscape but also people's attitudes to biodiversity...

Beavers were at work in Scotland long before people, but disappeared in recent centuries, largely under pressure from the human invaders who hunted them down for their pelts. In the mid-1990s, Scottish Natural Heritage started serious discussions on the reintroduction of beavers, and since then a number of initiatives – including field studies in Knapdale and Tayside – have provided valuable knowledge and experience that could benefit a lot of other rare, endangered species, including plants, shellfish and insects, as well as birds and mammals.

An early programme for the re-introduction of wildlife in Scotland was one for white-tailed eagles on the island of Rum, which started in 1975. During recent years, however, work has been done for other candidates, including the freshwater pearl mussel, the pine hoverfly, vendace, water voles and woolly willow. Much of this was started during the ‘Species Action Framework’ programme of targeted management which ran from 2007 to 2012. Other projects are also underway, including translocating golden eagles to the Dumfries and Galloway area, whilst others have already been completed, such as red kites.

To be successful, species reintroductions have to satisfy a wide range of criteria, including socio-economic and ecological factors. The beavers lived in Scotland up to about the 16th Century, but land use and the countryside have changed since then, and the impact the beavers will have is not easy to model in detail. Scientists know fairly well how beavers will behave, but the trial reintroduction of beavers in 2009 was the first government-approved project of its kind in the UK, and some effects on the environment are only beginning to be understood. For example, a study by the University of Stirling has revealed new evidence of beavers’ impact on loch plant communities and standing waters. It’s well known that beavers could have a potentially damaging impact on aspen, which grow in areas such as Speyside, where very careful management would be required if there was any future reintroduction; and in Knapdale, scientists are learning more about the impact of beavers on Atlantic hazel and on the lichen communities which thrive on them. However, says Gaywood, there is clear evidence that, overall, beavers can have a very positive influence on biodiversity.

Dr Martin Gaywood, Policy & Advice Manager at Scottish Natural Heritage (SNH), has played a major role in reintroducing the beavers and edited the report Beavers in Scotland, produced for the Scottish Government. In his view, beavers are not only “ecosystem engineers,” creating habitats and enhancing habitat diversity, but in the future might also become “employees,” helping to prevent floods by improving water management upstream. Beavers can also claim to be the only species, apart from humans, that can intentionally modify their environment by building structures, but the challenge would be to target their activities in specific areas, says Gaywood, “because they don’t always do what they’re told!”

As well as potentially helping flood management, beavers can also have negative impacts on land use – for example, by causing bank collapses and damming drainage ditches. A range of different management measures, such as tree protection, pipes in beaver dams, trapping and perhaps even creating special buffer zones, will continue to be tested and adapted over the years ahead. This could pose particular challenges for the programme in some parts of Tayside, where the beaver population is based on the River Tay and the River Earn, from Kinloch Rannoch to north of Dundee. Studies in Scotland suggest there might be little negative impact on fish such as pike, roach and perch, but more work is needed on salmon and trout. Another major aspect is the impact on public health. The Knapdale and Tayside beavers were tested for a range of parasites and diseases, but no evidence was found of any pathogens that may cause an increased health risk to humans, livestock or other wildlife. Genetic studies also keep a close eye on the beavers to check for inbreeding and hybridisation amongst the Eurasian beavers released in Scotland and, so far, there is no evidence of a different and unwanted species, the North American beaver, being present.

Gaywood’s report focused on the interactions between beavers and the natural and human environments, as well as legal and management issues – what was legal and allowable, and what to do if things go wrong. It also came up with four possible future scenarios, ranging from total removal to “accelerated reintroduction,” and in the end the Government opted for the beaver populations in Knapdale (which started off with three families of beavers in 2009) and Tayside (a total of about 40 families in 2012, originating from beavers which had previously escaped or been released without authorisation) to be retained, and for the Knapdale population to be reinforced. Since their reintroduction in Scotland, plans are also being made to make beavers a protected native species under European law by early 2018.

According to Gaywood, it was important to involve all the stakeholders right from the start, because no matter how the project was managed, everyone knew there might be some significant impacts on land use, particularly forestry, farming and fisheries, plus infrastructure. “One aim was to bottom out management needs,” says Gaywood, to make it easier to plan for future projects, advise land managers and reassure stakeholders. “We also aimed to be as flexible as possible,” adds Gaywood. For example, when there’s a collapse or a flood caused by beavers, or if a tree is felled next to a road, the landowners may need to act quickly, and SNH is aiming to set up a flexible, pragmatic approach to licensing work and has set up an advisory service.

Beavers in Scotland has been described as the world’s “most comprehensive, detailed and robust” report for any species reintroduction project. It is not just ambitious in scope, but also summarises the types of practical management experience gained in Eurasia and North America, and highlights what management issues will need to be addressed in the years ahead.

“We can't ignore the fact there have been some significant problems,” says Gaywood, but according to the report, “the benefits of beaver presence on Tayside are likely to outweigh the costs,” and the development of an appropriate management strategy “will therefore be key to the successful coexistence of beavers and fisheries, agriculture, forestry and other land uses, including necessary surveillance, monitoring and research requirements.”

Other species

Gaywood, who was also Project Manager of the Species Action Framework and a lead author of The Scottish Code for Conservation Translocations, points out that no species translocation will ever be cost-free or risk-free, but also believes there are valuable lessons to learn from the beavers with regard to other future species reintroductions. Despite some speculation in the media, it is highly unlikely that wolves or bears will ever roam free in the Highlands in the foreseeable future, but wildcats – “the Scottish Tigers” – are another major focus for Gaywood, who is also the manager for the SNH contribution to Scottish Wildcat Action. There has also been a lot of discussion regarding the lynx, but Gaywood believes that a lot of work would need to be done before the case can be made for reintroduction.

Beavers are popular creatures which capture the imagination of the general public because they are so “cute”, but all stakeholders have to be given the opportunity to be involved in the discussion or reintroduction will not succeed, and that means winning over the sceptics and educating the public on the knock-on effects, says Gaywood.

The wildcat project is an excellent example of the need to get people involved at community level, since one of the problems with wildcats is hybridisation – breeding with domestic or feral cats. To address this, the project has launched a scheme to “trap, neuter, vaccinate and release” feral cats, as part of a multi-pronged programme to “see what is out there” and understand the ecology better, including what has been described as “the biggest ever camera-trapping survey in the UK.” The project has also created a “stud book,” to profile the genes of the wildcat. Ultimately, this will lead to captive breeding of wildcats which will be set free at times and places still to be decided. “Stakeholder engagement is vital,” says Gaywood. “The wildcat was once persecuted because it killed game birds, but there are things we can do to ensure its survival.”

Species-focused conservation

According to Gaywood, species reintroductions could provide a range of benefits to Scotland, including tourism as well as the environment, but they are “only one tool” in the toolbox. “Some people also think that species-focused conservation is rather old-fashioned,” he adds, “but it's useful to focus on the iconic species which have wider impact, and that includes beavers and wildcats.”

Other species, such as white-tailed eagles and red kites, may also dominate the headlines, but some translocations slip under the radar, says Gaywood, because they are less contentious or simply not so well known, such as the pine hoverfly or woolly willow. “Television programmes such as BBC Springwatch draw attention to particular species,” says Gaywood, “and that is good because the viewers also learn about the wider issues involved, and the interaction amongst different species.” Another major issue is the need to remove invasive species from the wild. Rhododendron, Japanese knotweed and giant hogweed are troublesome plants on land. In freshwater, the North American crayfish, zebra mussel and New Zealand pygmyweed have major effects on native plant and animal communities. There are also many other problems such as water voles (recently reintroduced in Loch Lomond and the Trossachs) being threatened by the American mink and earthworm populations being severely impacted by the New Zealand flatworm.

The translocation code

The Scottish Code for Conservation Translocations (see below) which Gaywood helped to develop, in partnership with academics, landowners and other stakeholders, has become the standard guide for conservationists, and is the first of its kind in the world. Gaywood describes it as “the starting point” for species translocations, including plants as well as animals. Although it was devised for the environment in Scotland, the code builds on IUCN (International Union for the Conservation of Nature) guidelines and can be treated as an international reference point for similar projects, dealing with the “overarching issues” involved. There is also a big emphasis on people, says Gaywood, and the importance of getting the science right.

Gaywood summarises the issues as legal, biological and socio-economic. This covers everything from founder populations, husbandry and welfare to genetics and financial impact on different sectors; in effect, to “walk the practitioners through” what they will need to do to make reintroductions successful. “It is all about getting things done on the ground,” says Gaywood, “looking beyond single species to the wider environment.”

Whether you are introducing hoverflies or wolves, there can be complex “cascade effects” in every project, says Gaywood, and it's hard to predict every impact in detail. The basic question, however, is could this particular species survive? And if the answer is “Yes” and conservationists can win people over because their case is strong and meets the new criteria, we may see further recoveries of nature in Scotland – which will perhaps help human beings survive.


Beavers in Scotland

The Beavers in Scotland report was designed to support a government decision on the future of beavers.

It provides assessments of the interactions beavers may have on the natural and human environments, examines legal and beaver management issues, and presents a number of future scenarios for beavers in Scotland.

The issues surrounding beaver reintroduction to Scotland have been the subject of intense investigation and discussion over the last 22 years. The report draws on the experience gained through SNH-commissioned projects, the Scottish Beaver Trial, the Tayside Beaver Study Group, the Beaver–Salmonid Working Group, the National Species Reintroduction Forum and a range of other studies from Scotland and abroad.


Population explosion?

At the beginning of the twentieth century, there were thought to be only about 1,200 European or Eurasian beavers in eight populations in Europe and Asia. Today, the population is estimated to be at least one million, in 25 countries in Europe alone.



The Scottish Code for Conservation Translocations:

> Work out whether translocation is the best option – could other conservation actions provide a lower-risk and lower-cost solution?

> Develop a clear plan to deliver a well-defined conservation benefit.

> Obtain all necessary permissions and licences.

> Maximise the chances of success by understanding the biological needs of the species.

> Take great care to protect the species being moved and the habitat it is being released into, and avoid the spread of invasive species, pests and diseases.

> Where translocations may affect people, consult with land-users and other interested groups and individuals to identify ways the translocation can provide them with benefits, and do not undertake translocations that would cause unacceptable harm to people’s welbeing, livelihoods and recreational activities.

> Monitor the translocation and respond to any issues that arise.

> Keep people informed and share information about the translocation to guide future projects.












"Species Reintroduction". Science Scotland (Issue Twenty-one)
Printed from on 03/04/20 12:02:41 PM

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