Sheltering behaviour at lambing by Welsh Mountain ewes

Abstract

SUMMARYFrom observations made over 3 years on a flock of Welsh Mountain sheep kept at 210 to 330m above sea level there was no indication that ewes especially sought shelter for lambing when wind speed was under 8 km/hr or the Kata cooling power was below 20 millical/cm2 per sec. When wind speed or cooling power rose, lambing sites chosen by the ewes were progressively more sheltered. Average wind speed and Kata cooling power at sheep height at lambing sites were about 14 km/hr and 35 millical/cm2 per sec.Variability in wind speed and cooling power at an unsheltered site accounted for only 24% and 18% of the variability in these measures at the lambing sites, thus the lambing sites chosen depended to a considerable extent upon other factors, which are discussed.The environment at lambing sites chosen by ewes cannot be taken as the optimum. No attempt was made to correlate lambing site environment with ewe or lamb performance.