Project code: S-11-05

Duration 4 years

Team and Leader Jim McAdam (APSD), Lynne Dawson and Alistair Caron (ARINI)

Organisations Involved Animal Plant and Science Division and Agriculture Research Institute of Northern Ireland

Background and Summary

Current research evaluating the potential of crossbred ewes to improve lamb output and carcass quality in the hill sector has demonstrated significant improvements in prolificacy and lamb output at weaning through the use of Lleyn X Blackface, Swaledale X Blackface and Texel X Blackface ewes relative to purebred Blackface ewes. 

However the vegetation present in the hill environment in which the crossbred ewes are maintained must be able to support this extra performance without detrimental effects on the environment or the welfare of the animals.  In Northern Ireland, over 7,000 farmers participated in voluntary agri environmental schemes covering approximately 22% of the farmland area.  The schemes, which have been developed under the EU Rural Development Regulation (EC99/1257) focus on maintaining and improving biodiversity through the positive management of wildlife habitats, improving water quality of rivers and lakes by nutrient management planning and the adoption of the Codes of Good Agricultural Practice.

These agri-environmental schemes can comprise a significant proportion of producers income on many hill farms and the continued success of the scheme relies on maximising the benefits of sheep grazing for plant and animal biodiversity.  It is therefore important to ascertain if crossbreds can undertake this role as efficiently as the traditional Blackface breed and thus secure the substantial income from environmental schemes.

While grazing behaviour of sheep has been evaluated in some studies (Tomlinson, 1997), there is a scarcity of information on the effect of ewe genotype on grazing behaviour and the implications of differences in grazing behaviour / vegetation selection on flora and fauna biodiversity.  Also, in view of decoupling and associated cross compliance regulations which state that producers must manage the land in such a way to prevent both over and under grazing, research is required to establish the optimum stocking rate to maximise vegetation development on the hill.  While the effect of under grazing, particularly in heather based vegetation.  It is also important to establish a baseline to evaluate the impact of potentially radical changes in the industry which may occur due to the decoupling of subsides from agriculture production.

On the basis of this background information, this proposal aims to:

A.     To investigate the effect of crossbred ewe genotype on grazing behaviour and vegetation development
B.     To establish optimum grazing strategies in the hill to maintain plant biodiversity.


i)    Landscape monitor six hill farms (summer 2005 & 2006)
ii)   Monitor grazing behaviour of crossbred ewes (2006 to 2008)
iii)   Evaluate effect of grazing pressure on vegetation development (2006 to 2008)

Final report to be submitted to AgriSearch in December 2008


Related documents: Development of beef and sheep systems for improved sustainability, biodiversity and delivery of ecosystem services within hill areas of Northern Ireland (Project 12/4/08) - Technical Report