However, Mr Kerridge said some of the cases the SPCA was dealing with were becoming more "bizarre".
"Some of them you look at them and say, 'How could anyone do that?'."
In Dunedin, there were reports of a serial cat killer last week. In Auckland last month at least three prosecutions were brought against animal abusers in Auckland.
Last year, the SPCA received 13,823 complaints nationally compared to 13,089 in 2011.
It took 44 prosecutions, seven more than in 2011.
SPCA inspector manager Alan Wilson said there was no doubt prosecutions for cruelty had risen but it was difficult to know why.
"We are seeing a rise in prosecutions but maybe it was too low before. It's hard to know whether we're just detecting more of it or whether the stuff we are detecting is having an impact."
Auckland lawyer Anita Killeen wrote in last month's New Zealand Law Journal that a decade ago crimes against animals were not viewed as very important and did not deserve punishment in the same way other crimes did.
But she said a February High Court decision in which a home detention order for a farmer who broke the tails of 115 cows with a steel pipe was quashed and substituted with two years' jail, showed a shift in the value society placed on the punishment of such crimes.
"It responds to Parliament's view that cruelty to animals is abhorrent to society and its clear intention through the unanimous passage of the Animal Welfare Amendment Act 2010 to ensure that animal cruelty is to be treated seriously by the courts," she said.
Animal rights group Paw Justice co-founder Craig Dunn said the severity of the cruelty was increasing.
"You've got some pretty horrific cases and these have to be looked at. These are serious issues that people are actually doing to animals and the next step is on to children, then females and other males."
Maxwell Johnson, of Mangere, was last month jailed for six months for savagely beating a puppy which lost an eye, five teeth and suffered a fractured jaw and broken right foreleg.
"It's not just beating an animal, it's the severity of how he beat the animal. It is really scary."
Paw Justice is poised to launch several animal abuse prevention campaigns this year including one which features a song by New Zealand musician Tiki Taane.
The song will be released in September and was composed from lyrics suggested by some of Paw Justice's 260,000 Facebook followers.
Mr Dunn urged people to report any abuse and said laws introduced in 2010 gave judges more power when sentencing offenders.
"If you see it, report it. You can change all the laws you want but unless you get change in society you'll never stop it."
The SPCA was also ramping up campaigns to combat the issue including more emphasis on the importance of desexing.
Mr Kerridge said the SPCA had recommended the soon-to-be- updated Animal Welfare Act state that New Zealanders recognise animals as sentient beings - capable of feeling pain. "It's radical. But if the Animal Welfare Act starts with that statement then we should have an act that does not allow animals to suffer in any shape or form," he said.
Hamilton veterinarian Dr Keith Houston said it cost him thousands of dollars every year to subsidise treatment for abused and neglected animals brought in by the SPCA.
Dr Houston, an SPCA animal welfare committee member, said the Waikato's four inspectors logged 380 complaints last month alone.
"So it is definitely increasing."