Chief executive Andrea Midgen said about 45,000 animals came through SPCA branches all around the country - animals who were sick, injured, abused or abandoned.
Of those animals, about 80 per cent consisted of kittens and puppies.
"There's a huge issue with animals being sold that haven't been desexed,'' she said.
"So it's a bit of a problem when they go for a wander and get up to mischief and then suddenly we are dealing with thousands of kittens coming in over the summer months.
"We spend a lot of our time desexing these kittens and puppies and then adopting them out.
"Money like this really helps us to prevent that problem from happening.''
In Auckland, about 10,000 animals were cared for by the local SPCA, based in Māngere, each year.
Because of educational pamphlets, desexing campaigns and better awareness over the years, the figures of animals not desexed were markedly lower.
One of the big issues of not having cats desexed was the impact on birdlife, as a result.
"If you get a situation where a cat has a litter of kittens and it's not being taken care of as such, they will forage for survival."
Auckland Airports spokeswoman Helen James said: "We love playing our part in protecting the environment and believe this regional campaign will not only have a positive impact on conserving native birdlife, but also ensures we have more healthy cats in our communities.''
