Doc coastal biodiversity ranger Jim Fyfe said it expected about 20 pups to be born this year.
There are 28 potential breeding sea lions.
Three pups have been born so far, two at Warrington to sea lions Joy and Hope.
Hope gave birth on December 22 and Joy on Monday, Mr Fyfe said.
Joy had been "working hard" at breeding over the last few years, but it was good to know more sea lions in the area were actively breeding.
"Hope has come through."
The recovery of the species was amazing and "like getting the moa back," he said.
They had almost been hunted to extinction by early settlers of New Zealand and their numbers had only grown in the past 25 years due to conservation efforts
They were remarkable creatures with dispositions similar to that of a golden retriever.
Doc tracked the breeding of all sea lions, but it was not concerned with seeking out every new pup. The priority was ensuring all pups that had been born in public areas were safe and given time to grow before they departed with the mother about three weeks after birth.
Sea lions would probably breed until the third week of January, but pups would be around the birth site until the end of February
Anyone who had found a sea lion should contact Doc to ensure the animal was safe, he said.