Selwyn District Council has emailed dog owners in the area to remind them about their responsibilities.
There are about 70 dogs being added each month to the district council’s database.
The numbers of registered dogs recently topped 15,000.
Larger numbers of dogs, particularly in townships, can bring challenges, the council said in the email.
"One area of concern that has been brought to our attention lately is the number of dog faeces being found at some of the domains," the council said.
"So this is a perfect time to remind everyone that when you are out exercising your dogs please pick up after them and please don’t leave the plastic bags lying around. If the rubbish bins are full it’s your responsibility to take it home.
"In 2012 we worked extremely hard to open up most of the domains and reserves in Selwyn to off-leash exercise areas.
"This came with a rider that problem areas may have that privilege revoked.”
