Biodiversity

Peatlands form the UK’s largest extent of semi-natural habitat and play an important role in conserving a wide range of species. Many of these species are rare and/or declining and are priorities for conservation action.  

Showcasing peatland biodiversity 

The twin crises of climate change and biodiversity loss are two of the biggest threats facing humanity and the many species with which we share our planet, and on which we depend. These two crises are inextricably linked, and restoring peatlands provides a nature-based solution which addresses both. The valuation of biodiversity alongside other ecosystem services such as carbon storage is critical to ensuring peatlands are valued in a way which further incentivises restoration and helps provide the economic support needed.  

Introducing fascinating and diverse species is a key tool for increasing nature connectedness, engaging people with peatlands and advocating for their restoration and protection. Throughout 2024, the Peatland Programme is celebrating peatland biodiversity through a series of monthly showcases featuring a particular peatland species or species group. 

The first of our showcases introduces the Sphagnum mosses and their role in ecosystem function, informing restoration practice and inspiring creative collective action.  

The second of our showcases looks at testate amoebae and their role in peatland ecosystems and the science of palaeoecology – how understanding the past of our peatland habitats can inform their restoration today.

The third of our showcases explores the importance of dunlin as an indicator species for peatland health, and the threats facing them, including forestry plantations on peatlands. 

The fourth of our showcases focuses on the iconic cottongrasses, their key role in peatlands including as indicator species, and how citizen scientists are helping return them to areas where they have become scarce. 

The fifth of our showcases celebrates the large heath butterfly and the peatland restoration and reintroduction efforts that are bringing back this priority species to areas of its former range.

The sixth of our showcases features Atlantic salmon and the importance of good water quality, such as that provided by healthy peatlands, for this economically important species.

The seventh of our showcases features desmid algae, microorganisms that are key to the ecological function of peatlands, but about which we still have much to discover.

The eighth our showcases features the water vole, the UK's fastest declining mammal, and discusses how peatlands can be an important habitat for this much-loved species.

If you have a peatland story you’d like to share through one of our showcases, please get in touch at info@iucn.org.uk.  

Peatland habitats 

Peatlands include many different habitat types with varying environmental conditions and associated ecological communities. Rainfed peatlands such as blanket bogs and raised bogs are acidic and nutrient-poor, supporting specialist species adapted to these challenging conditions. Despite covering only 0.2% of the world's land mass, the UK is home to 13% of the world's blanket bog, a globally rare habitat with unique biodiversity. 

Fen peatlands have developed under a wide range of wet conditions in all parts of the UK, from low-nutrient, acidic and bog-like through to high-nutrient and base-rich. This diversity of environmental conditions and associated habitats means a great number of species are found in the fens, many of which are now geographically restricted and rare. Large fen complexes provide some of the only habitat in the UK for many threatened species, including common crane (Grus grus) and spotted crake (Porzana porzana). The British race of swallowtails (Papilio machaon britannicus), one of the UK's rarest and most spectacular butterflies, is currently only found in the fens of the Norfolk Broads¹. 

Peatland specialists 

The acidic, low-nutrient conditions found in many peatlands have led to unique adaptations in species that are not found anywhere else. For example, all 13 species of carnivorous plant recorded in the UK are found in bog habitats: sundews (Drosera spp.), butterworts (Pinguicula spp.) and bladderworts (Utricularia spp.) all have special adaptations which enable them to capture and absorb nutrients from their invertebrate prey.  

Sphagnum mosses, key peat-forming organisms in many peatlands, grow best in comparatively low-nutrient, acidic conditions, and can manipulate their environment to further promote these conditions. These mosses provide a complex and diverse substrate on which other organisms can thrive, and play a critical role in flood and drought resilience and carbon sequestration. 

Fen peatlands are extremely important for biodiversity, supporting over a third of the UK’s true flies and large numbers of beetles, moths, spiders and plants. Fen specialists cover a wide range of taxonomic groups, particularly invertebrates and flowering plants².   

Many aquatic peatland invertebrates are habitat generalists adapted to low levels of dissolved oxygen in the water. Some, like the bog hoverfly (Eristalis cryptarum), are peatland specialists. This species, despite having a wide distribution across Europe, Siberia and Mongolia, is now critically endangered in the UK and known only from a few sites on Dartmoor. The white-faced darter (Leucorrhinia dubia), a small but distinctive dragonfly species, has declined significantly in the UK due to the loss of the lowland bog pools in which it breeds, but reintroductions to restored peatlands are supporting its recovery³. 

Peatlands are associated with certain parts of the lifecycles of many birds and mammals, such as the breeding season or during migration. Golden plover chicks (Pluvialis apricaria) are perfectly camouflaged to blend in with the open mossy habitats where their nests are found. Invertebrates such as craneflies provide an important source of food for the chicks of these birds and other peatland breeding species such as red and black grouse (Lagopus lagopus and Tetrao tetrix) and dunlin (Calidris alpina).  

Protecting peatland biodiversity 

The loss of global biodiversity is occurring at an unprecedented rate, with an average decline of 69% in species populations since 1970. Individual species are being lost 10 to 1,000 times faster than the normal ‘background’ rate of extinction. A number of international and national policies are in place to address this crisis, but as yet have largely failed to prevent these declines. Many peatlands in the UK are designated as protected sites for their national and international importance for biodiversity, but in many cases, the condition of these sites is unfavourable, and many other peatland habitats are undesignated⁴.

There are now many policies which recognise peatlands for their often highly specialised biodiversity, including the Ramsar Convention on Wetlands and the United Nations Convention on Biodiversity. During the International Union for Conservation of Nature’s World Conservation Congress in 2016, the IUCN adopted Resolution 043: Securing the future for global peatlands. Since that time, many countries, including the UK, have adopted peatland-specific strategies, and the Peatland Programme plays an important role in monitoring and advocating for peatland restoration in the UK.   

The IUCN’s National Committee UK, of which the Peatland Programme is a part, includes a number of expert Working Groups supporting the various IUCN Commissions. The Protected Areas Working Group (PAWG) provides analysis and advice in support of the UK Government’s aspiration to protect 30% of the UK’s land and 30% of its seas by 2030. PAWG recently published a review of 23 land and sea designation types for biodiversity conservation against IUCN definitions of ‘protected area’ and ‘other effective area-based conservation measures’, presenting evidence on the effectiveness of the current management of these areas for biodiversity.  

References: 

1. Collins N.M., Barkham P.J., Blencowe M., Brazil A., Kelly A., Oldfield S., et al. Ecology and conservation of the British Swallowtail butterfly, Papilio machaon britannicus: old questions, new challenges and potential opportunities. Insect Conservation and Diversity. 2020;13(1): 1-9. https://doi.org/10.1111/icad.12371. 

2. Mossman H.L., Panter C.J., Dolman P.M.. Fen Biodiversity Audit. University of East Anglia; 2012. Available from: https://www.cperc.org.uk/downloads/5_Fens_Biodiversity_Audit_FINAL_Report_24-10-2012.pdf.  

3. Meredith C. Reintroduction of Leucorrhinian dubia (Vander Linden) (White-faced Darter) to Delamare Forest, Cheshire. J. Br. Dragonfly Society. 2017;33(1): 50-72. 

4. Lindsay R.A., Clough J. In Joosten H, Tanneberger F, Moen A, editors. Mires and Peatlands of Europe. Stuttgart: Schweizerbart Science Publishers; 2017: 705-720.