Ms Rolfe said she'd had tins of cat food thrown at her and had to have abusive members of the public trespassed.
"We are constantly being abused. People think their pets are disposable and when we tell them we don't have the room to take them on, they get very aggressive."
She said the shelter was currently at full capacity, with about 200 animals.
Ms Wallace said people abandoning their cats when they moved was also common.
"It's easy for people to leave cats behind rather than go through the struggle of trying to find a rental property that will allow pets. That's when the cat colonies start appearing which is a major community issue, particularly in areas that have a high turnover of tenants."
Both Ms Wallace and Ms Rolfe said landlords should consider easing restrictions on pets to help solve the problem of pet dumping.
Rotorua Rentals co-director Richard Evans said the current rental market may have exacerbated the problem, but it was not landlords' responsibility to solve the issue.
"If a person is renting and decides to get a pet, they have to live with the consequences. It is their right to get a pet, just as it is the right of a landlord to decide they do not want animals on their property."
Mr Evans said of all the properties his business managed, only about 1 per cent allowed pets.
Renter Rebecca Skipwith has been trying to find a new place for the last couple of months after being given an ultimatum by her property manager - either get rid of her dog, Indy or move out. She considered putting Indy up for adoption but could not go through with it.
"She's my baby. . . I can't get rid of her."
Tips for re-homing your pet:
• Take great photos showing your pet at its best.
• Describe your pet's personality in detail.
• Consider approaching friends or family for a temporary home to ease the pressure.
• Get the message out - advertise online, post on Facebook, create a flyer, put a listing in the newspaper.
- SPCA New Zealand