Conservation grazing - a management method

Conservation grazing is a management technique that can be used in a variety of habitats, from heathland and grassland to woodland. Different species of grazers are appropriate for different sites, depending on the existing habitat and conservation aims. The desired outcome of conservation grazing is typically to increase plant diversity and shift the plant community from grasses to herbs and wildflowers. Grazing species and breeds should be chosen considering their feeding preferences, physiology and behaviour. Typically, the grazers chosen are native breeds, as they are usually hardy and can tolerate a varied diet which is sometimes low in nutrients. Multiple species are often used together as their selective eating creates a varied habitat structure. The effect of conservation grazing on the environment mimics the grazing of ancient animals including bison, tarpan (Eurasian wild horse) and auroch (wild cattle). Wild extant species such as beavers and red and roe deer can also be used in conservation projects alongside livestock. 

Cattle can be used in open areas and woodland. They are not particularly selective when grazing so will eat vegetation avoided by other livestock, including sedges and rushes. Cows eat by wrapping their tongue around vegetation and pulling it up, which creates varied heights in the sward. Due to their large size, cattle can be used on sites with dense vegetation such as bracken, as they can push through and trample it. Their trampling can be beneficial to reptiles and invertebrates, as it creates open spots for sunbathing. On the other hand, grazing by cattle may have negative impacts on some reptile species - populations of smooth snakes in heathland have been shown to increase when grazing is stopped.

Cattle dung can be valuable in ecosystems - over 250 invertebrate species can be found on cow pats. Most conservation projects minimise inputs, meaning cattle are only wormed when necessary, so the wildlife value of their poo is maintained. 


At sites with public access, livestock breeds must be chosen carefully. The cattle seen here on a pubic footpath are British Whites, known to have a generally docile nature.


British White and Sussex cattle grazing on a nature reserve, Hampshire

Sheep are more selective grazers than cattle, and snip the vegetation using their lower front teeth against a dental pad. This creates a uniform, short sward. If sheep are kept at too high stocking densities they can create soil compaction problems. Sheep are unsuitable for sites where the aim is natural regeneration of woodland, as they browse on saplings and strip bark. Sheep may also be unsuitable for some grassland sites, as they will select flower heads, however, this can be managed by adjusting the timing of grazing. Due to their small size, sheep can be a positive asset at sites inaccessible to larger animals, and are typically easier to handle. 


Sheep being used in a conservation grazing scheme, Hampshire

Ponies can also be used for conservation grazing - they graze grasses very short and typically leave flower heads, and will also browse scrub and trees. Like other species, they can cause trampling problems if kept at inappropriate densities. An example of the use of ponies is on saltmarsh managed by the Scottish Wildlife Trust in Angus, where they maintain open areas which benefits wading birds. 


Ponies grazing at Bowthorpe Marshes, Norwich

Conservation grazing has some benefits over potential alternative management methods. Burning or mowing grassland and heathland causes dramatic and sudden habitat change, and leaves behind a uniform structure with less wildlife value than the mosaic created by varied grazing. Many nature conservation sites are difficult to access with large machinery due to waterlogged ground or steep topography, and even where machinery can be brought in, it may damage the ground. Using grazing animals can be cheaper, more convenient and less labour intensive than using machinery. Some projects are also able to make profits from selling beef, lamb and venison from their grazing animals. 


A sign to educate passers by about the conservation grazing on university fen at UEA.

When managing land for nature, conservation grazing has the potential to be a sustainable strategy to increase biodiversity, but careful considerations should be taken when deciding on species, stocking density, timing and the ultimate aim for the land.

More information can be found in these websites, papers and publications:

https://www.nationaltrust.org.uk/woolbeding-countryside/features/conservation-grazing
https://scottishwildlifetrust.org.uk/our-work/our-wildlife-reserves/conservation-grazing/
https://www.hiwwt.org.uk/conservation-grazing

Woodland Trust - Conservation grazing in woodland management
Habitat use by smooth snakes on lowland heath managed using 'conservation grazing'

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