Information released under the Official Information Act said the council received 409 RDO applications for the period between January 1 and November 21, an increase of 155 from the same period in 2017.
Council compliance team leader Elle Dickson said the council actively promoted responsible dog ownership.
She said animal services assessed an owner's history, as well as carrying out a full property inspection to determine whether they met RDO criteria.
Owners meeting the RDO criteria pay $30 less than the standard registration fee. Desexed dogs had a further discount.
Mrs Dickson said registration fees were used to fund animal services activities.
"The intention is that the dog-related side of animal services is funded by dog registration," she said.
"Registration fees can only be used on dog-related activities."