The guards spent two days searching for Jarod Lineses, 16, who was swept out to sea at Ninety Mile Beach on December 27. His body was found on New Year's Day.
Mr Ross said he could not understand the spike in incidents. Usually there were one or two rescues a season.
Overall, the beaches around Northland have been busier, with almost as many rescues in the past four months as the whole previous season. The season runs from Labour Weekend to Easter.
A spokesman for Surf Life Saving New Zealand said since Labour Weekend, lifeguards had attended 36 rescues in Northland. However, in the previous year, from May 31, 2013, they had attended 39. Since Labour Weekend, they had also attended 14 searches, which was equal to the entire previous year.
The Northland Emergency Services Trust (NEST) helicopter had a busier December than last, recording 132 hours compared to 86 in 2013.
NEST operations manager Dean Voelkerling said it had "certainly" been the busiest summer in the last five years.
"We seem to have been to a lot more swimming accidents and beach accidents compared to other years," Mr Voelkerling said.
"I think there are just more people out and about doing things at the moment, certainly compared to five years ago when you had the economic downturn."
He said it was not just his team that was busy, but also coast guard, fire service, St John and the surf lifesaving clubs.
The emergency department at Whangarei Hospital had its busiest day on January 2, with a record 150 admissions.
Three people have drowned in Northland waters this summer, including 11-year-old Jahzel Porter in the mouth of the Waipu River on Monday.
