Almost two million more lambs are on farms this spring, according to Beef + Lamb New Zealand's Economic Service.
The extra lambs come after ewes were in top condition for mating, economist Rob Davison says.
However, this season's 26.9 million lamb crop is still the third-smallest since the early 1950s. Only the previous two years were lower.
This means that after replacements are kept, 20.5m lambs will be killed for export, an increase on last year's 18.9m. The average carcass weight will be 18.3kg.
Davison says slightly more ewes were mated in autumn at a time when there was plenty of feed. This lifted the country's average lambing percentage to 123 per cent from 119 per cent.
While there will be more lambs, lamb prices have plummeted this year to $5-6 a kg early in the season, compared to more than $8 a kg this time last year.
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