Animal welfare officials are shocked after a cat shot seven times in the head with a nail gun was found near Kaitaia.
They warn that whoever was responsible could turn their attentions to people.
Kaitaia SPCA inspector Bridget King said the body of what had been a young, healthy adult tabby female was found in the stream behind the Waipapakauri Hotel last week.
"It was a proper builder's nail gun that was used, not the sort a do-it-yourselfer would have in the garage," Ms King said.
"The cat appears to have been shot at close range, and the first nail probably killed it, but whoever was responsible just kept shooting it."
The cat was not thought to have been feral and the SPCA wanted to hear from anybody who may be missing a female tabby or knew somebody who was.
SPCA national chief executive Robyn Kippenberger said there was an established link between animal abuse and violence to humans. An amendment to the 1999 Animal Welfare Act in 2010 raised the penalty from three to five years' jail for wilful cruelty that resulted in death with suffering or permanent disability.
"The link between animal abuse and human violence is well researched and undeniable. The recent increased sentences send a clear message that violence, whether to animals or humans, is unacceptable and society will not tolerate either," Ms Kippenberger said.
"We hope that the higher penalties will act as a deterrent to potential offenders and give animal abuse increased significance for those who may be able to report such acts to ourselves or the police."
She cited international research that animal cruelty was a precursor to a wide variety of antisocial behaviour, including violent and non-violent offences.
Anyone with information about the cat can call the SPCA for free on 0800 428 464 or Kaitaia police on 09 4086500.