A builders' merchant who killed racing dogs with a bolt gun and buried them at his home has been fined £2,000.
David Smith buried the animals near his home
David Smith, 57, of Northdene Terrace, Seaham, admitted disposing of the greyhounds without a permit.
Judge Peter Armstrong said he would have jailed Smith had this been an animal cruelty case, but accepted the police and RSPCA had investigated.
Magistrates previously heard Smith had put down about two dogs a week for the past two years, at a cost of £10 each.
He was fined at Durham Crown Court following a private prosecution by the Environment Agency, after police said he had committed no offence.
It had been claimed that Smith, who was also ordered to pay £2,000 costs, had shot about 10,000 dogs, but magistrates were earlier told the figure was nowhere near that.
He was questioned by police, but it was confirmed the bolt gun used to kill the retired greyhounds was held legitimately.
Following a six-month investigation, the Environment Agency prosecuted him under legislation used to restrict the dumping of waste.
He admitted a single charge under the Pollution Prevention and Control (England and Wales) Regulations that, on 12 July 2006 he disposed of waste - the bodies of deceased dogs - on land without a permit.
Greyhound protection group Greyhound Action held a protest outside the court on Friday, and said it was disgraceful that the dog racing industry itself was not in the dock.
A spokesman for the British Greyhound Racing Board (BGRB) said the organisation was disgusted by what had happened at Seaham, and that an investigation was ongoing.
Animal welfare was its highest priority, and had improved "vastly" in recent years, he added.
Inquiries by the RSPCA concluded that there was no indication animal cruelty laws had been broken.
A spokeswoman for the charity said if used properly a bolt gun was a humane method of killing dogs and there had been no evidence that Smith had killed the greyhounds inhumanely.
However the spokeswoman was critical of the dog racing industry.
She said: "It's vital that racing greyhounds are given the protection they deserve through proper independent regulation.
"The greyhound racing industry needs to clean up its act and ensure the dogs' welfare is a top priority."