The club recorded 31 rescues over the 2018-19 season, outlined in a report released by Surf Life Saving New Zealand.
Sunset Beach, in Waikato, recorded the most rescues — 40 — while Muriwai Beach near Auckland had 32.
St Kilda club president Peter Gibbons said although St Kilda lifeguards had 31 rescues, many were not at the beach but were credited to St Kilda lifeguards.
"The number does not mean St Kilda is the third most dangerous beach in the country.
"It’s indicative of how busy we are. It means we have very active, committed and dedicated volunteers who do a lot outside our beach."
The number reflected that Surf Life Saving NZ was the 24/7 agency for water rescues, Mr Gibbons said.
St Kilda lifeguards were involved in rescues in Otago Harbour and at other beaches.
He said while there were issues with rips at St Kilda, the 31 rescues included those at non-patrolled beaches such as Smaills Beach.
"I think the biggest issue is people’s behaviour in open water in their own time and own space.
"When a rostered patrol is out there are no issues. The issue is people’s behaviour outside of this.
"A lot of those rescues happen later at night when we aren’t there and later in the evening."
The increase in rescues was affected by a rise in the number of people going to St Kilda Beach, due to erosion and a lack of parking at St Clair, he said.
Surf Life Saving NZ southern region manager Stu Bryce said the St Kilda club would receive extra support over the summer, with an extra lifeguard on duty.
"At other beaches there are three guards, but we will have four instead of three."
Regional patrolling for the summer season begins tomorrow.
Lifeguards will be posted at the four main Dunedin beaches seven days a week, from 11am to 7pm, for the next six weeks.
