A farmer is fuming after a mare, Dolly, and foal were shot dead in a paddock in what he believes is an attack by "low-lifes".

Stephen McGrath made the grisly find as he drove past the paddock on his way from Upper Buller to Murchison at 10am yesterday.

The horses were dead but still warm and he believes they were shot in the early hours of the morning.

"I used some pretty profane words," he said. "It looked pretty horrendous, if I could get hold of them [the attackers] I would wring them."

It looked like the six-month-old foal had been shot more than once, and because there was a full moon he did not believe it was a case of mistakenly identifying the horses for deer.

"There's no reason, it's low-lifes," an upset Mr McGrath said.

Dolly, a 13-year-old quarterhorse-thoroughbred-clydesdale cross, used for riding and farm work, belonged to his 16-year-old daughter Rimu, who last month won the TrustPower Nelson Tasman Youth Community Spirit Award.

The family lives at Newton Livery, where they have 11 other horses.

Mr McGrath, who has lived there for 38 years, said he couldn't think of anything that serious that would cause someone to shoot their horses. "Probably it's just complete idiots," he said.

He had been on his way to Murchison in a horse and wagon to be used for a wedding today, and was with a friend.

They called the police and an officer went to the farm yesterday. A police spokesperson said the shooting would be investigated.

- © Fairfax NZ News