The SPCA is urging pet owners not to leave their cats and dogs at home while going away on holiday.
The organisation's Auckland chief executive Bob Kerridge said the SPCA expects to visit dozens of homes over the next few days to rescue animals that have been locked up alone.
Mr Kerridge said pets left inside become hot, hungry and very distressed.
He said some people think the animal will be fine for a week on its own if they leave enough food out, but a pet dog will eat a week's worth of food on the first day it is left alone.
"Its possibly just ignorance, they just don't realise that their animal does need daily attention."
Mr Kerridge said staff have in the past found dogs locked up in garages and tool sheds during the New Year period.
The SPCA has also been receiving more than a hundred unwanted kittens a day at its Auckland shelter.