As with many students at the University of Glasgow Garscube campus, I have taken a lot of joy from study breaks wandering around the nearby Dawsholm Park. To me, the greatest wonder of Dawsholm is the seeming incongruity of the Highland cows living in the park within view of the surrounding city and the wild forest of the rest of the park. With a healthy dose of curiosity and information provided on placards near their field, I was inspired to do some digging. The City Council website indicates that the cattle were first placed in the park in 2007 to help manage the green space less intensively and promote the growth of native wildflowers, however that was not the entire story (1).
Via personal communication with the City Council and the Acting Assistant Livestock Supervisor at Pollok Country Park, Melissa Lurinsky, I learned about the rather complicated history of the cows in Dawsholm Park. Under current management practices, they have lived in the park for over ten years. Before that, they were present in Dawsholm during the 1990s where, at some point, grazing rights were lost. Conservation grazing was cited as a reason for reintroducing them in the early 2000s, specifically controlling scrub and Hawthorn trees growing in the field, but they were also keenly missed by locals. The main figure championing the reintroduction of cows to Dawsholm was Robert Hastie, the former manager of Pollok Country Park and resident of Dawsholm Park. Conservation grazing with the cattle has been used to great effect in other areas of the city, notably in Pollok Country Park (2).
The practice of managed grazing, or conservation grazing, has been widely used to manage habitats non-invasively. The Royal Society for the Protection of Birds (RSPB) uses the managed grazing of approximately fifty head of cattle and six hundred sheep on the island of Oronsay to maintain habitat for endangered bird species (3). The Woodland Trust is another major UK-based organization, focused primarily on restoring and rejuvenating forests. They have extensively documented their use of grazing animals to encourage the growth of native species. In forests, they have used various combinations of grazing animals, mainly cattle but also sheep, ponies, goats, and pigs, to restore them to their historic state, particularly to aid recovery from the planting of non-native conifers during the twentieth century (4).
The varied feeding practices of grazing animals result in multiple benefits, and animals are selected based on what sort of environment they are needed to maintain. Sheep are selective grazers, and they will bite fairly close to the ground, preferring to select the softer shoots and buds of plants and avoiding the parts they deem overly stemmy. They are well suited to rougher terrain, but they can compact the soil in more lowland environments. Cattle feed by wrapping their tongue around taller plants and pulling, resulting in a mixed height of the remaining plants. Due to their larger mouths, they are also less selective than sheep and will often select whatever is most abundant in an area to eat. This practice helps to select for diversity and allows plants to reseed and increase in abundance. In a field that is not overstocked with cattle, characterized by a balance between muddy bits and untouched soil, the deep footprints will create micro-environments and puddles to support invertebrates (bugs) of all kinds, as well as helping to plant seeds (5,6).
In addition to the type of species, other factors determining how grazers will affect their environment are the stocking density and the location of management infrastructure in their field. As evidenced by Barcella et al. and understood by anyone who has had to move livestock through the same area of a slightly muddy field day after day, damage to the field will be highest wherever the management infrastructure is. That could include water troughs, shelter, gates, or where supplemental feed is supplied (7). Stocking density is the other key factor determining what level of effect the grazers will have on their habitat. Ideally, in conservation grazing, there will be enough livestock to maintain the habitat by preventing succession, the growth of extra scrub and young trees. However, you also have to ensure there is enough food available so that the animals do not eat things the managers want to maintain, like mature trees, while avoiding supplemental feeding (8).
Constant monitoring of stocking density should be the most labour-intensive part of conservation grazing. The proper formula of the number and type of animals can be difficult to determine. While supplemental feeding may be necessary and is used for the Dawsholm Park cattle, (you can sometimes observe them getting fed if you make your way to the northeast corner of their field early in the mornings), ideally it will be avoided for conservation grazing to reduce the cost of additional inputs to the system (8). The cattle at Dawsholm are members of the Pollok Fold, primarily managed at Pollok Country Park, and are on-site from late July through spring of the following year. Usually, between six and eight animals of one to two years of age are required to maintain the field without overgrazing. During the spring, the cattle are moved to other pastures so that the field in Dawsholm has time to regenerate before they return in late summer (2).
While much of the evidence of the benefits of introducing livestock for conservation grazing of previously grazed land was primarily anecdotal when such schemes were being adopted in the late 20th and early 21st century, recent research has been able to provide quantifiable evidence in favour of such practices. Rupprecht et al. compared plant composition changes between grazed land and abandoned plots of land and were able to show that grazing increased numbers of endangered species. Another positive effect was a decrease in leaf litter and woody material. Importantly, the species that tended to succeed more in grazed areas were shorter, compared to those tall-growing, competitive, and often invasive species in the non-grazed areas (9). While specific studies of the changes in plant species in Dawsholm Park have not been conducted since the cattle were first introduced, it is safe to say they are having a net-positive impact on their little ecosystem, not solely through conservation grazing, but also enchanting their visitors and many admirers in the community.
1. Dawsholm Park - Glasgow City Council [Internet]. [cited 2021 Feb 28]. Available from: https://www.glasgow.gov.uk/article/16584/Dawsholm-Park
2. Lurinsky M (Pollok CP. Dawsholm Park Highland cattle research. email to Catherine Fedor. 2021.
3. Oronsay [Internet]. Royal Society for the Protection of Birds. [cited 2021 Feb 28].
4. Haw K, Aylward S, Bateman S, Cleaver M, Evans J, Jenkins J, et al. Wood Wise Woodland Conservation News: Conservation grazing in woodland management [Internet]. Grantham, Lincolnshire; 2012 [cited 2021 Feb 28].
5. Rook AJ, Dumont B, Isselstein J, Odoro K, WallisDeVries MF, Parente G, et al. Matching type of livestock to desired biodiversity outcomes in pastures - a review. Biol Conserv [Internet]. 2004 Nov 21 [cited 2021 Feb 28];119:137–50.
6. Dumont B, Rook AJ, Coran C, Röver K-U. Effects of livestock breed and grazing intensity on biodiversity and production in grazing systems. 2. Diet selection. Grass Forage Sci [Internet]. 2007 Jun 1 [cited 2021 Feb 28];62(2):159–71.
7. Barcella M, Filipponi F, Assini S. A simple model to support grazing management by direct field observation. Agriculture, Ecosystem, and Environment. 2016 Oct 16;234:107–17.
8. Gilhaus K, Hölzel N. Seasonal variations of fodder quality and availability as constraints for stocking rates in year-round grazing schemes. Agriculture, Ecosystem, and Environment. 2016 Oct 16;234:5–15.
9. Rupprecht D, Gilhaus K, Hölzel N. Effects of year-round grazing on the vegetation of nutrient-poor grass- and heathlands—Evidence from a large-scale survey. Agriculture, Ecosystem, and Environment. 2016 Oct 16;234:16–22.
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