He said a digger had to be brought in to dig a hole big enough to take the mauled bodies.
"We have no final tally yet but it's going to be over 40."
Several sheep were left with wounds and they would have to be assessed.
Flaxmere Police Constable Greg Andrew said another nearby farmer had also lost several sheep to a marauding dog, or dogs, about two weeks ago.
He said the maulings added to the damage being done to local farmers' flocks by poachers.
Last week offal and sheep skins were found dumped in Stock Rd near the Te Kura Kaupapa School in Flaxmere.
Mr Andrew said stock theft was a "major issue" in the region.
"So we don't need this as well."
He said the damage to several of the sheep was extensive, and some had crushed lower jaws which indicated the dog which attacked them was large and powerful.
"Others were found with torn legs and wounds to stomach areas."
He said it was hard to tell whether it was just one dog or several.
The similarity to the previous incidents indicated the same dog or dogs may be involved, and Mr Andrew said until they were found the threat to sheep in the area was high.
He said while dogs could travel some distance to prey on sheep he believed the dog, or dogs, responsible for Sunday night's attacks were likely to be local ones.
"They would have arrived home with a fair amount of blood on them and probably fibres of wool."
Several of the dead sheep were splattered with mud and the dogs too would have ended up with mud on them.
The farmer put the value of the sheep at about $105 a head which meant the loss would cost him more than $4200.
