Body condition and ranging behaviour of blackface hill sheep in relation to lamb survival.

Published online
01 Jan 1982
Content type
Journal article
Journal title
Journal of Applied Ecology

Hewson, R. & Verkaik, A. J.

Publication language


Factors affecting the production and survival of lambs, including vulnerability to predation, were studied in a flock of about 850 Blackface hill sheep in Argyll, West Scotland. The poorer production of lambs by gimmers (sheep breeding for the first time), was not due to a lower pregnancy rate or to poorer body condition, but may have been affected by poorer maternal care. Lambing reached a peak between 4 and 10 May. Sheep withdrew from the flock to lamb and returned within 1-3 days. If the distance between sheep and their lambs is regarded as a measure of vulnerability to predation, then lambs of ewes were less vulnerable than those of gimmers. Sheep moved uphill at night, but less so in June than in February-March. The numbers of sheep within a circle of 50 m estimated diameter increased between afternoon and evening. The anti-predator value of this behaviour is discussed. Home ranges in the lambing period varied from 33 to 55 ha, with a mean of 44.4 plus or minus 1.7. These were larger than in other studies of hill sheep in Scotland.

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