"It's kind of hard for 10 puppies to make their way out into the middle of the Paraparas," Ross-Waitai said.
Wilson said the person who brought the puppies to them had stopped after seeing one puppy on the road, at which point they found the other nine.
One of the 10 puppies, which was particularly cold and malnourished, had since died despite the treatment given by SPCA staff, Wilson said.
The other nine were currently recovering, with SPCA staff feeding them four meals a day to bring them up to a healthy weight as well as having their health checked and getting them fully vaccinated.
Once the puppies were fully healthy and vaccinated, the SPCA would look for foster homes to take them in, which Wilson expected them to be ready for by next week.
The past weekend had been a particularly busy one for SPCA Whanganui, with another six puppies and their mother being surrendered on Saturday.
However, Wilson said this winter had not been especially busy overall.
"It's just the norm, we always get quite a few animals in," Wilson said.
With the 10 puppies likely having been dumped on the Parapara, Wilson and Ross-Waitai urged people to get in contact with SPCA and bring in unwanted puppies rather than dumping them.
"Dumping isn't necessary as there are so many people here to help," Wilson said.
People who planned to bring in puppies should let SPCA know ahead of time, she said.
Last month 22 cold and starving puppies were found alongside the Waimakariri River and handed into SPCA Christchurch, with one unable to be saved. A spokesperson said it was the highest number of animals in a single dumping in the Canterbury region for about 10 years. The surviving pups are now living in foster homes before forever homes are found.
Anyone interested in providing a foster home for the Whanganui puppies can register by clicking on the "Volunteer" link of the "How you can help" menu on SPCA's national website spca.nz.