More than 19,000 abandoned and neglected animals have passed through Auckland's SPCA shelter this year - a 7 per cent increase on last year's figures.
And the organisation is preparing for up to 150 animals to arrive every day during the holiday season.
Operations manager Tracy Dunn said the SPCA was often the ambulance at the bottom of the cliff.
"It would be great to see people taking responsibility and having their pets desexed to avoid the constant overpopulation of unwanted animals that we deal with every Christmas," she said.
The Weekend Herald today starts its annual Adopt Me series. Each day through summer, an animal available for adoption at the SPCA's Mangere shelter will be featured.
Throughout December, the Auckland SPCA has already been inundated with cats and kittens. Warm temperatures and high humidity meant that the kitten season started early this year, said Ms Dunn.