In 2017-18, average production per effective hectare and production per cow were both higher in the South Island than in the North Island.
Twenty-three percent of all dairy cows were located in the Waikato region, followed by North Canterbury (14.0 per cent), Southland (11.7 per cent) and Taranaki (9.6 per cent).
There were 2 million cows in the South Island in the 2017-18 season, North Canterbury's average herd size of 803 being the largest.
Farms in the South Island were on average larger than those in the North Island, both in terms of farm area and cow numbers.
The average herd size in both islands increased this season.
Hawke's Bay's average herd size of 664 was the largest in the North Island.
The smallest average herd sizes were in Auckland (273), Taranaki (295) and Northland (319).
South and North Canterbury had the highest average cows per hectare (3.44 and 3.43 respectively).
The regions with the lowest average cows per hectare were the West Coast (2.21) and Northland (2.28 per cent).
Otago was home to 5.4 per cent of the national dairy herd population, and Southland's proportion was 11.7 per cent.
Otago had 445 herds, a total of 267,874 dairy cows, and 91,438 hectares effective.
Southland had 982 herds, a total of 583,240 cows and 221,343ha effective.
Southern Rural Life