Devon has long supported a rich diversity of important habitats and species. However, many of these habitats have experienced significant declines in recent years. Much of the Devon landscape has been simplified as a result of the focus on commercial agriculture, forestry, and urbanisation.
The loss of habitats and species has been considerable. Arguably Devon’s most important habitat, Culm Grassland, declined in extent by 50% between 1984 and 1990. During this period more widespread habitats such as hedges declined by 20% and alarmingly only 41% remain in good condition today.
The Met Office developed the Habitat Resilience Tool for Devon as a joint venture with the Devon Wildlife Trust (DWT) in 2012. This has been used extensively by DWT to support their nature recovery projects across Devon. Ten years since the tool was developed, some of the people who worked on it from the Met Office and DWT look back on the development process and how the Devon landscape has changed in the years that followed.
The challenge was clear: to restore habitat resilience as well as the components required to secure habitats, helping them to increase in number, become larger in size and improve in quality. In order to identify habitat resilience in Devon, the team developed five indexes to represent different components that collectively influence how robust our habitats are.
- Habitat status index – reflects the relative importance of the habitat. Habitats with higher status and better legal protection are given higher resilience values.
- Positive management index – ranks areas across Devon by how well managed the land is. Better managed land is assumed to relate to a habitat with higher resilience.
- Climate sensitivity index – the sensitivity of habitats to the effects of climate variability and climate change. More sensitive habitats are given lower resilience values; less sensitive habitats have higher resilience values.
- Habitat fragmentation index – the size, shape and distance from one wildlife rich area to another affect the resilience of that habitat. The ability for species to move between habitat fragments was also incorporated. Higher resilience areas occur in larger, connected regions with high quality matrix of land in between.
- Topographic index – a more varied landscape allows species to move and populations to change at a given site. This index links areas with greater variation in elevation, slope and aspect to those with higher habitat resilience.
According to Dr Debbie Hemming and Neil Kaye from the Met Office, who worked on developing the tool, “The Habitat resilience tool has been designed to support Devon Wildlife Trust, and other land managers, to make appropriate decisions to manage our environment, such as implementing measures for species conservation or planning land use and green infrastructure activities. The tool combines Met Office expertise in plant science and geographical web tool development with knowledge and information on our environment held by Devon Wildlife Trust and Devon Biodiversity Records Centre.”
Peter Burgess, the Director of Nature Recovery at DWT, also helped develop the tool and is the main user. He said, “The Habitat Resilience Tool has proven to be a great asset in supporting the development of large-scale nature recovery projects in Devon – from works to reconnect landscapes to threatened great horseshoe bat populations which forage over large landscapes, to targeting of focal landscapes for the restoration of internationally important Culm grasslands. The tool supports high level decisions to prioritise key landscapes for concerted conservation effort between DWT and a wide range of partners.”
The population of Greater Horseshoe Bats (GHB) has declined by 90% in the UK during the last 100 years. Similar trends are seen across northern Europe, with Devon now a stronghold for the species.
Another species which has flourished in Devon over the past decade is the wild beaver. This has been reintroduced as part of the River Otter Beaver Trial, England’s first wild beaver re-introduction project, pioneered by Devon Wildlife Trust. In 2022, Devon has thriving beaver populations on several rivers in addition to the River Otter, including growing beaver populations on the River Tamar and the River Taw.
A key area of biodiversity in North Devon is the Culm Grassland, located between Exmoor and Dartmoor, which has led to many referring to it as ‘the land between the moors’. Its name refers to the predominance of Culm Grassland, a mix of purple moor grass and rush pasture.
It is also a landscape facing enormous challenges. Many elements of modern farming do not support the financial health of the small, mixed farms that predominate in the Culm; tourism is underdeveloped and the area’s geographical isolation all means that this is a place of significant economic deprivation. The unique landscape that is so key to the economic health of the area and to people’s well-being is disappearing. 90% of the Culm’s unique habitat has been lost since 1950.
Working in partnership
Using the Habitat Resilience Tool, DWT and other land managers across Devon are able to track and study landscapes and habitats more thoroughly and pinpoint areas which are in need of more resources.
The success of the Habitat Resilience Tool for Devon for supporting DWT with the development of large-scale nature recovery projects in Devon has highlighted the potential for this tool to be replicated at other locations. This possibility is currently being explored for other wider Wildlife Trust areas across the UK.
DWT will continue to use the tool to help strategically guide new and ambitious projects alongside the Devon Nature Recovery Network Map. DWT is currently exploring the feasibility of reintroducing wildcats to the South West and the tool has already informed initial landscape appraisals.
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