This experiment evaluated the effect of stocking intensity at lambing on lamb survival. A randomised block design with three replicates compared stocking rates of 16 and 30 ewes/ha. Twin-bearing Merino ewes (N=69) that had been mated with Poll Dorset x White Suffolk rams were placed in paddocks sheltered with rows of hessian, with 8 or 15 ewes per 0.5 ha plot for the low and high stocking rates, respectively. The survival of lambs born alive at the high stocking rate (63%) was 24% less (P=0.002) than for those at the low stocking rate (83%), and was associated with a higher (P<0.05) proportion of lambs dying from starvation/mismothering/exposure. There were no differences (P>0.05) in lamb birth weight, marking weight, ewe live weight or condition, suggesting nutritional conditions between the stocking rates were similar. The results suggest caution in using lambing strategies which require high stocking rates.