Southland farmers expect to be counting further losses on Tuesday after a fourth night of very cold temperatures, snow and wind.
More than 20cm of snow has fallen in the region since Friday. Coastal areas of Southland are especially hard hit.
Some farmers say its the worst snowfall in at least 40 years, catching them in the middle of lambing.
David Rose, who farms near Winton, says it's come at the worst possible time for sheep farmers.
He says they've been work frantically since Friday to save stock.
Meanwhile, Jim MacDonald, who farms at Mount Gowrie Station at Clark's Junction, inland from Dunedin, says it's been a wake-up call, (showing) that winter is not yet over.
He says most farms in his area are on the verge of lambing and aside from losing newborn lambs, they could lose some ewes if there is further snow this week.
Mr MacDonald says the biggest effect will be if the snow lies for more than 48 hours.
Slink Skins Ltd expects lambing losses to be the worst in 40 years.
Manager Ray Watson expects that by the time the storm has cleared, lamb losses will amount to thousands in some areas
Slink Skins collects and processes the skins and carcases of dead lambs and calves.