Mixed grazing systems benefit both upland biodiversity and livestock production

10 Feb 2015

Take home message: Mixed upland grazing systems improve livestock production and benefit biodiversity, suggesting a ‘win-win’ solution for farmers and conservationists. The economic and environmental sustainability of upland sheep farms could be improved by using farming systems which include a combination of cattle and rough grazing. Scientists at Aberystwith University and University of Hull found that a beef and sheep system could reduce methane emissions and improve bird diversity compared with sheep-only enterprises. The findings could have implications in helping the livestock industry find ways to tackle greenhouse gas emissions whilst improving production and conserving biodiversity. In the study researchers conducted field experiments consisting of five management systems to test the effects of progressively altering elements of an upland farming system. The experiments included incorporating cattle grazing into an upland sheep system, integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, and altering the stocking ratio within a mixed grazing system. The final experiment compared the effects of grazing belted galloways with limousin-cross cattle. The impacts on livestock productivity, the numbers of birds and butterflies and the estimated methane emissions were measured over four years. The study found that management systems which incorporated mixed grazing with cattle improved livestock productivity and reduced methane emissions, compared to sheep-only systems. Systems which also included semi-natural rough grazing supported more species of birds and butterflies, and it was possible to incorporate bouts of summer grazing of these pastures by cattle without compromising cattle performance. The researchers did not find an improvement in bird and butterfly diversity when they compared grazing the belted galloways with  limousine-cross cattle. In addition, methane emissions from the belted galloways were predicted to be higher than the grazing limousins. Fraser, M. D., Moorby, J. M., Vale, J. E., & Evans, D. M. (2014). Mixed grazing systems benefit both upland biodiversity and livestock production. PloS One, 9(2), e89054.