The dogs were found by National Parks and Wildlife Services rangers roaming in Winburndale Nature Reserve after being lost for several days.

Robert Tilley, 23, of Lyal Street, Bathurst was fined $400 and ordered to pay $58 costs by magistrate Gail Madgwick in Bathurst Local Court as a result of the incident.

Tilley was fined over the two hunting dogs he claimed were lost in the Sunny Corner State Forest.

Police prosecutor Sergeant Brett Donaghy handed a statement of facts to the court outlining how Tilley's dogs were trained to jump off vehicles when they picked up the scent of pigs.

Tilley and companions followed the dogs, killing pigs with knives, the court was told. It was alleged Tilley was hunting wild pigs on Saturday, March 5 near Snow Gum Road in Sunny Corner State Forest when the dogs ran off.

It was not until Sunday, May 6 when a ranger fox baiting came across two dogs near a half eaten pig, near Big Flat Fire Trail. The dogs, with bloodied muzzles, were aggressive and the ranger stood 15 metres away to take photos.

Tilley with another ranger went to the Winburndale Reserve to recover the dogs on May 8. The radio collars and breastplates were taken by NPWS as evidence.

NPWS regional manager Nick Rigby said it was the responsibility of owners to keep their dogs under control.

"Like all nature reserves the 10,050 hectare Winburndale Nature Reserve is dedicated to the preservation, conservation and study of wildlife and natural environment," Mr Rigby said.

"It is a place for people who want to experience and appreciate the bush and is very popular with bird watchers."

Mr Rigby said dogs are not allowed in national parks and nature reserves where they can escape, become wild and breed with other wild dogs, creating strong and dangerous populations that threaten farm animals and people.

"Dogs can be a nuisance to the natural environment, even a real menace to children and older persons. Dog faeces and urine are a health hazard to wildlife and pollute waterways," he said.

"Dogs prey on native fauna, killing small animals and stressing larger ones, frightening them away leaving unprotected young. Just the scent of a dog can frighten native animals."