Mr Hancock didn't find anything amiss when he checked out the paddock but saw a shrub move as he was returning to the car. Looking closely, he saw a Pakeha man in his 60s trying to keep out of sight. He was lying on top of two dead pigs, one boar and a sow pregnant with up to a dozen young.
The man got up and started walking away while Mr Hancock fired a barrage of questions and dialled 111.
Mr Hancock followed him over fences and across farmland, keeping a few metres back because of the large knife strapped to the man's belt.
The man then began to tire and police caught up about half an hour later, he said. The man was taken to the Kerikeri station for questioning.
Only later did Mr Hancock find the pigs had been shot. That someone had used a rifle on the family's land, near their house, made his mother uneasy.
"And as far as I see it, that's armed robbery," he said.
Mr Hancock suspected at least one other pig had been taken, going by the three pools of blood in the paddock.
He had about 40 pigs, a mix of large whites and kunekune-crosses. He kept them as a sideline business but spent so much time with them they were almost pets.
Mr Hancock said his parents earned little from running beef cattle and rare-breed Pitt Island sheep on the 120ha farm.
The ongoing thefts would be less upsetting if the rustlers were genuinely hungry, but the fact that up to 20 sheep disappeared at a time suggested it was for money.
Stock theft was so common in Northland many farmers didn't report it, he said. He urged anyone affected to inform police.
Mr Hancock's mother, Deryth Hancock, said she put a lot of effort into breeding her sheep.
"So it's really upsetting when people come in and kill pregnant ewes and lambs willy-nilly. They seem to think they're there for the taking," she said.
- A Bay of Plenty man aged 69 has been arrested and charged with theft of animals. He is under strict bail conditions and is due back in the Kaikohe District Court on Tuesday. A firearm has been seized.