A response from Gen Crisford - Engagement Officer for the National Trust on the Purbeck beaver feasibility project

Thank you for attending the Planet Purbeck meeting and for so many good questions in the breakout rooms. The below answers cover only the specific topics which were asked about in this part of the meeting. If I’ve missed anything or if you don’t find all the information you need here, please feel welcome to contact me on gen.crisford@nationaltrust.org.uk

You can also find further information at these three helpful FAQ links:

Project specific questions 

*For more information about the Purbeck project please see: [Re-introduction of beavers to Purbeck | National Trust] which contains an attached PDF [purbeck-beaver-project-hased-proposal-summary.pdf (nt.global.ssl.fastly.net)] to summarise the current proposal for a phased reintroduction project.

How can I help/get involved?

 There will be many ways that you can help over the coming years if we are able to bring beavers back, including volunteering activities. At the moment, whilst we continue to look at how this will work for everyone, there are a few ways that you can easily get involved:

  1. Learn lots about what beavers do and why they do it. Learning accurate information will help to dispel false rumours and help other people to understand. (We can help with this!)
  2. If you are feeling excited about beavers do share your excitement to inspire others. For beavers to make a comeback they will need support from the community and Planet Purbeck can be a big part of this.
  3. Talk to your friends, families and neighbours and get the conversation started - whether they are a beaver believer too or nervous about a beaver reintroduction. Remember it is all about listening to each other so that we can find ways of making this work. If they would like information, please give them my contact details.

Thank you!


Now that a project proposal has been produced and communicated, we need to receive permission from DEFRA to proceed with phase one. If/when this is achieved, we will go about confirming funding and putting any required management infrastructure in place. The timescales for a release will therefore be very dependent on the licencing process, so it is difficult to be precise with any predictions. If all goes well, it will be possible sometime in the next year.

Is Little Sea a freshwater habitat?

Although Little Sea originated as a landlocked body of seawater, this water is now fresh and is replenished by acidic, oligotrophic water draining off the adjacent heathland, which then flows through the dune slacks and into the sea. Little Sea has been classified as freshwater for over 100 years now and is a highly suitable habitat for beavers.

Will there be fencing around Little Sea and will beavers break out into Poole Harbour? 

The land around Little Sea at Studland is recommended for phase one because of the highly suitable habitats, and because it is naturally contained by sea and dry heath, both inhospitable habitats to the freshwater species. Beavers are therefore unlikely to spread easily from here until the available territories within the Little Sea catchment have been exhausted and territorial pressure has increased over time. Therefore, fencing should not be necessary to contain them. Should escapes occur beavers can be easily identified by trail signs, trapped and relocated. Should there be evidence of repeated escapes, additional mitigation measures such as targeted beaver fencing around the points they are escaping from could be installed. The policy for containing the beavers to the Little Sea catchment could also evolve if phase 2 becomes a possibility and as national policy develops.

Where will the beavers come from? 

England’s beavers are currently mostly sourced from Scotland. Despite regulations on health screenings, there are strict restrictions on importing animals from outside the UK to ensure control of foreign parasites. As a result, animals which have been trapped in conflict situations on the River Tay make good candidates for licenced projects in England.

Where will the beavers be released? Will additional animals be released later?

 If beavers are released into the Little Sea catchment, logistics allowing, they will likely be released next to the open water, in an area with plenty of willow. Up to 3 pairs of beavers could be released here under licence, but each pair would need to create a different territory to avoid fighting. Therefore, they would be released in different areas. The habitats around Little Sea have an abundance of willow trees so they/we will be spoilt for choice in finding suitable locations.

Should the project proceed to phase 2, it is likely that additional releases would be desirable, to widen the genetic diversity and to allow for a new population to begin, producing additional mates for the Little Sea beavers as they begin to disperse over time. Release sites within the wider Purbeck Heaths National Nature Reserve are yet to be confirmed in the detailed planning of a phase 2 project and a separate licence would need to be requested for permission to releases beavers here. Beyond designated project areas, it is likely that natural expansion of existing populations will be responsible for the spread of beavers throughout the countryside (again, if national policy allows for it).

Timescales for beavers migrating outside the initial project area

 It is very difficult to provide timescales for long-term migration, but it will certainly take time. Eurasian beaver dispersal is slow, especially at the beginning of a reintroduction when numbers are so low. Unlike most other rodents, beavers are monogamous, producing only one litter (ca.1-5 kits) per year. Young will disperse to find a mate and establish their own territory after 2 years, gradually expanding the population range within the catchment. Only when catchments reach capacity, will neighbouring catchments begin to see beavers migrating via wet areas or short overland stretches.

It is currently possible to use templates from previous projects such as the River Otter, where predicted dispersal can now be compared with the initial phase of reality, but different habitats and food availability will have a big impact on this too. Specialised modelling programs are now in development to help with these kinds of questions.

The proposed phased reintroduction for Purbeck is made up of several stages, each which has criteria to be able to begin, and an exit strategy at the end, to evaluate the process, so this again will work on an evolving timescale. Wider policy will also dictate how and where beavers are able to settle and in what timescales when we start to look at longer-term spread throughout the county. 

Monitoring of habitats and beavers

Ecological impacts are expected to be positive, but they will be closely monitored as a part of a reintroduction project. Detailed information on species and habitats has been regularly collected at Studland already, which will act as baseline data to monitor any changes here. Beaver welfare will also be monitored via remote trail cameras and visual observations of individual animals; with particular attention paid to body & coat condition and behavioural changes. Each released beaver will be tagged with a sub-cutaneous microchip PIT transponder to allow for identification of individual animals if they are trapped and/or handled. Coloured ear tags may be used for easy identification from a distance, but radio tracking will be unlikely due to the challenges of safely attaching transmitters.

Exit strategies

An exit strategy allows for a way of removing beavers from the landscape should the overall net impact of the reintroduction be negative. Whilst this is highly unlikely, it can help to build confidence that we are not entering into an irreversible situation. Should the exit strategy be implemented, the beavers would be trapped by experienced personnel and either used to supply other projects or otherwise re-homed. At the end of each project phase, one of three things will happen: (i) We proceed to the subsequent phase (if & when the criteria is achieved); (ii) There is no transition to the next phase, but beavers are allowed to stay within the existing area; (iii) The project comes to an end and all the beavers are captured & relocated elsewhere.


To date this project has been funded by private donors and business, as well as money left in trust for nature recovery projects such as this. The next phase of the project will be funded in the same way, with fundraising taking place once a licence has been granted to proceed.


Flooding Puddle Mill if beavers occupy the Corfe River: 

Thank you for highlighting Puddle Mill as an area of concern, which can be added to our information about potential impacts in the Upper Corfe River area. This is outside the proposed project area so beavers will not be reintroduced here but may later naturally spread here over time if the national beaver policy being developed by the government allows. We understand the importance of support being available for residents and this is recommended within the ongoing development of long-term management plans. Should a beaver reintroduction go ahead, a local management strategy will need to allow for active management of beaver impacts. For example, should localised flooding risk a negative effect on property or access, this will be a top priority for mitigating action such as lowering dams, using flow devices to control water levels, or removing dams when necessary to maintain a sufficient flow of water. It is expected that government will also clearly reflect this requirement in national policy, which we expect to see later this year.

Angling concern & fish migration

(River Corfe / River Frome): Unlike man-made obstacles and weirs, beaver dams are permeable structures, with water channels flowing over and around them. Fish are generally able to make use of these passages, continuing their migratory journeys upstream without difficulty. There is evidence at some sites however, that certain fish species may be temporarily affected, especially during periods of low flow, or in artificially contained streams, where the water is unable to spread out as it would naturally.

This issue can often be rectified by some rain, creating new bypass channels or even breaking down the dam in higher flows, and there is evidence to support that beaver dams do not hinder fish passage on a catchment scale, or for any significant length of time. But should it be determined to be causing an issue, intervention to notch or lower a dam can help to resolve this and alleviate concerns. Clear agreements may need to be in place to allow for this as part of a management strategy, as has been trialled in Devon with the “Protocol for the Assessment of Beaver Dams to Aid Fish Passage (PAD)”; and key migration routes through smaller headwaters must be proactively identified - as damming activities are limited to smaller (4th order) headwaters and streams/ditches.

Whilst the River Frome falls beyond the boundaries of a Purbeck project, we are already working together with fisheries organisations here to discuss this topic. Migration throughout the Corfe River has been identified as a more local consideration and we are investigating baseline data for monitoring fish migration here. Continued research can help us to better understand this issue, and find good management solutions, so that fish can also benefit from the habitat improvements that beavers can produce.

Conflicts with dog walking

Beavers are not an aggressive species and will avoid people and dogs, diving underwater with a slap of their tail to indicate danger. If cornered or kits threatened, beavers can effectively defend themselves and so it is advised that dogs be kept under close control when in a beaver territory. The initial areas we are looking at in Purbeck are largely already managed for nature and so there is already active engagement to promote responsible dog-walking. However, it is important to communicate effectively with visitors and local residents, both through on-site signage and educational opportunities, about how to walk dogs safely near beaver habitat. This will be developed and ongoing throughout the project period and the wider spread of information will also be important should beavers become part of our native wildlife across the country.

Compensation for productive land lost to nature

 After looking at the experiences of prior reintroductions and talking to our local stakeholders, we fully understand the importance of developing financial schemes, either to compensate in a case of productive land lost or to incentivise for making space for nature. The government is planning to trial a scheme over the next year which would compensate farmers for leaving a buffer zone around water courses. Alternatively, discussions with our partners indicate the possibility of developing a local scheme to pay for impacts with funds offset by reducing nitrogen runoff into Poole Harbour; or to pay landowners for benefits in carbon storage and biodiversity gain to incentivise buffer strips alongside rivers.

It is also anticipated that opportunities for funding will be available through the imminent Environmental Land Management Scheme (which will replace European agricultural subsidies), which is expected to offer benefits to landowners providing ecosystem services, opportunities for nature and access for people. 

Policy is also needed to assign long-term responsibility for beaver management, including the provision of advice and practical support whilst people learn how to live alongside beavers again. The government is expected to produce details of the national policy for this later this year, following a consultation into the future management of beavers in Britain. Continuing to develop local solutions, in line with national policy will form a key part of bringing beavers back to Purbeck.

What else is being done about nutrient runoff?

Whilst re-naturalising rivers to improve water filtration is a big part of future solutions, minimising excess nutrient runoff at the source is also important. In Poole harbour, many organisations and farmers have been working on this issue for some time, leading to the development of a pioneering partnership management scheme. The Poole Harbour Nutrient Management Scheme (PHNMS) has been put together by the NFU and farmers to create a solution to the issue of nutrients from agriculture causing environmental damage to the internationally designated wildlife areas in Poole Harbour. The scheme is farmer led/managed and aims to reduce the amount of nutrients going into the harbour, whilst creating opportunities for farming, new income streams and improving the environment. More information can be found here: https://www.nfuonline.com/nfu-online/south-west/news/phnms-summary-document-june-2020/  


Whilst management agreements and confirmation of the status of beaver in England are yet to be put in place, illegal poaching of wildlife is a serious offence and would be dealt with accordingly.

Lethal control: Many practical management options to mitigate any unwanted potential impacts of beavers are available and well documented. In areas where beaver impacts are unacceptable, as a last resort, they can also be easily and humanely trapped and relocated if necessary. Initially, whilst beavers are trying to re-establish in this country, there will be a strong preference for trapping and relocation, as there is widespread suitable habitat available and an urgent need for nature recovery. When countries reach a “cultural capacity”, this can be developed into a culling licensing system.

Scotland has not reached a cultural capacity of beavers but has employed lethal control. One of the problems in Scotland has been that the River Tay beavers returned to an area right next to/within an area of Prime Agricultural Land, characterised by being very productive, relatively flat and reliant on good drainage. As an accidental/unauthorised release, there was no prior consultation or planning with local farmers or authorities. Current legislation in Scotland currently bans the translocation of beavers from Tayside to suitable habitat outside the current range, and as a result, lethal control is being permitted on around 10% of the current range of beavers in Tayside. As the beaver population has naturally expanded from these areas, conflicts are much less or non-existent, benefits can be realised and where adverse impacts do occur there is much more potential for mitigation. Translocations to licenced enclosed projects in England are currently permitted, so this is where most of England’s beavers currently come from.

Eco-tourism: We recognise that tourism is an essential part of the Isle of Purbeck’s economy (not just for the National Trust), but that this also brings challenges for the landscapes we need to protect and for the locals who live here all year round. We are working closely with statutory authorities, partner NGOs, local community groups and local businesses to develop a sustainable tourism strategy for Purbeck, beginning this year with a focus on the Purbeck Heaths NNR landscape, in a project led by the Dorset AONB team. Planet Purbeck has a Sustainable Eco-tourism meeting coming up on March 16th if you would like to know more about what is going on in this area.

Giardia (Giardia lamblia): Giardia is a gut parasite already present in Britain. It can be carried by almost all mammals and is not especially associated with beavers as a species, despite some media attention in the U.S.. Regular sampling and analysis of water quality in the Scottish Beaver Trial showed no significant increase in levels of Giardia or Cryptosporidia. Norway has around 75,000 beavers and despite much of the rural population having water supplied from untreated streams the only Giardia lamblia outbreak in recent years was near Bergen, where beavers are absent. Giardia can be removed from water by normal filtration methods and there are no reported instances of European beavers causing health problems in humans from Giardia lamblia.

General Beaver Questions

Otter relations: As beavers eat vegetation and otters eat fish, they are not competitors. Otters can predate on young kits and so there is evidence of beavers chasing them away, especially when their kits are small and defenceless. However, beavers and otters often coexist, with otters making use of abandoned beaver burrows and the abundant fish found in their wetland habitats.

How much water does a beaver need? When we think of beavers, we often imagine a big river with a big dam across it. But in fact, if beavers are in a habitat where both the water is deep enough for easy travel (around 70cm or more), and there is easy access to food supplies, they won’t need to do so much to change it. They will only build dams if they wish to raise the water level, and only in smaller streams and even ditches, where the power of the water will not wash their attempts away. As so, beavers will happily occupy lakes, ponds and larger rivers, with little impact, burrowing into raised banks or lodge building by the side.

Can beavers provide eco-therapy?

Spending time in nature has been shown to help relieve stress and anxiety, improve mood, and boost feelings of happiness and wellbeing. Whether by improving our habitats, helping to recover other species or just providing by people with a new reason to get outdoors, beavers are a charismatic species and can certainly provide benefits to people.


How can we clearly communicate potential conflicts to people without scaring them? I am a big believer in a mixture of honesty, optimism and positive solutions. Concerns or passions for different topics don’t need to lead to friction between different interest groups, but they can do, if the reasons are not widely understood, or if we don’t listen properly to each other. It is therefore important to illustrate why some people may feel differently about the topic of reintroducing beavers across the whole landscape, so that people can work together towards finding good solutions, rather than arguing and ending up doing nothing. We are working hard to prepare solutions and agreements which will work well for everyone and take any worries into consideration.

It is important to have access to accurate information about both the benefits of beavers, and the impacts they can have so that false rumours do not spread and create problems that don’t exist. Please do put people in touch with us if they would like any information. It is important to remember that negative impacts are limited to very specific situations (they do not happen everywhere), and that they are manageable. It is also important to remember how beavers can help and the implications of things staying as they are. If we educate our community and enable people to be involved in the process, I am sure that we will come together and find a way of making it work.

How to involve the youth 

Young people can also get involved by learning about beavers, their habitats and the environmental issues that they may help us to improve. Why not check out some beavery activities at https://lodge.beavertrust.org/activities/

At the moment the Purbeck project is still in development, but over the coming months we will start to ask for help in developing educational materials and opportunities e.g. written communications, visual communications, events and educational activities. Anyone with a passion for the subject and a good imagination will be welcome to contribute. Start thinking up your ideas now!


I love the idea of a Purbeck Beaver Believer car sticker – are there any local companies who may like to take advantage of this budding business opportunity?


Some of the organisations we are working with
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram