Sheep grazing on upland moors emit less methane and carbon dioxide than those kept on improved grassland, a major new study has found.
The findings come from research carried out in the Yorkshire Dales and show how forage type and landscape influence greenhouse gas emissions from upland sheep systems.
The research is part of Forage for CH4nge, an Innovate UK-funded project supported by the National Sheep Association (NSA), which brings together farmers and scientists to investigate the environmental impact of upland sheep farming.
This project compared commercial Texel crossbred ewes with native Swaledale ewes grazing different types of forage across the Yorkshire Dales National Park.
The results showed that sheep grazing unimproved bog forages produced significantly lower methane and carbon dioxide emissions than sheep grazing improved grasslands and herb-rich grasslands further down the valley.
NSA is working with partners including the Game & Wildlife Conservation Trust, UK Agri-Tech Centre, Scottish Rural Universities, Yorkshire Agricultural Society and local farmers to ensure we deliver practical, farm-relevant evidence.
The results showed that Swaledale ewes produced less methane overall than Texel-bred ewes, but this was mainly due to their smaller size, and the difference was minimal when emissions were adjusted for live weight.
Both breeds of sheep produced more methane per day when grazing improved grassland than when grazing herb-rich grassland or moorage forage.
A similar pattern was seen for carbon dioxide, with native Swaledales emitting lower overall emissions than crossbred ewes, even after adjusting for body weight.
For both varieties, carbon footprint was higher on the improved herb-rich grassland than on the bog forage.
The forage types studied reflected typical upland systems, ranging from fertilized and reseeded ryegrass lays, to long-established unfertilized pastures, to upland rough pastures dominated by heather and bilberry.
NSA project manager Nicola Noble said: “This study provides important evidence that helps demonstrate the current and future importance of sustainable upland sheep farming.”
She added, “After working on this project for about a year and a half, it’s great to finally be able to share these results.”
The trial involved 120 sheep, split evenly between Swaledale and Texel crossbred ewes, and grazed on one of three diets.
Methane and carbon dioxide emissions were measured using a mobile portable accumulation chamber on a farm near Leyburn, North Yorkshire, and sheep were monitored individually under controlled, low-stress conditions.
The study also addresses the role that upland landscapes play in the broader climate, highlighting how aerated wetland and upland grassland soils act as methane sinks.
NSA policy manager Michael Priestley said: “The sheep sector is committed to achieving net zero by 2040 and methane reduction will be part of this, alongside improved genetics, nutrition, herd health, efficiency and reduced dependence on fossil fuels.”
Adrian Thornton-Berry, lead farmer on the project, said: “CH4nge’s feed is about demonstrating that farmers are key to a sustainable future for Britain’s uplands.”
He added: “By working with native varieties like Swaledale, we can farm in a way that protects these delicate landscapes for future generations.”
The findings add to the evidence that upland sheep systems can reduce agricultural emissions while continuing to support biodiversity and food production.
