Junior Black Fins Coach Matt Cairns said he and the other coaches were "so proud" of this team who fought "incredibly hard" to get their first title.
"It was an effort by the whole team and management to dig deep for the silver fern to get this result. It had never been done before but we knew we had the best team for the job," Cairns said.
"The team showed amazing resilience when things got tough and kept fighting by putting out massive performances and a lot of personal bests after four days of extremely tough racing."
All up, team members broke another three New Zealand pool records, and took home an impressive nine medals, including five golds, on the last day of competition.
The Kiwi domination of the 4 x 25 metre Manikin Relay extended to the junior women's team when Mount Maunganui's Tessa Bradley led off for Lucy Makaea of Piha, Macy Burns of Wellington and Claudia Kelly from New Plymouth as they beat Spain by nearly three seconds to take the gold medal.
The junior Black Fins picked up a bonus gold medal for being the winners of both the junior men's and women's races in the Manikin Relays.
Meanwhile, the Black Fins, the defending champions from 2016, finished the World Championships in second, a mere 20 points behind Australia. With 20 points awarded for a race win, the margin was small, and despite the Black Fins putting in a "mammoth effort", they couldn't catch Australia on the final day.
Black Fins head coach Jason Pocock said they were disappointed with the outcome, but proud of our effort all week, saying they were beaten by a better team.
"To the Australian team, we say congratulations, thank you for the battle and you were simply better than us over the five days."
Their last day was filled with strong results including three gold and six silver medals across a variety of events. The New Zealand relay teams, made up of four athletes in each race, won gold in the Ocean Woman and Ocean Man relays, renowned as a tough event combining swim, ski, board and sprint legs.
Omanu's Max Beattie and Pāpāmoa's Kodi Harman were part of the Ocean Man Relay triumph, with Harman, the country's best beach sprinter, bringing the team home.
Pāpāmoa's Natalie Peat and Olivia Eaton, representing Mount Maunganui SLC, joined Danielle McKenzie and Olivia Corrin to win the Ocean Woman Relay.
However, Danielle McKenzie and Cory Taylor both took silver in the most gruelling event of the whole competition – the individual Ocean Woman and Ocean Man races, covering a 1200m course that includes a swim, board and a surf ski leg, and a beach sprint finish – but the catch – they had to do it three times, back-to-back, with only a couple of minutes rest in between.
Olivia Corrin was 4th in the women's race, and Max Beattie 6th in the Ocean Man.
The Black Fins won the trophy for top team in the pool. The points were tied with Australia, but the Kiwi team won the trophy because they won more golds than their rivals.
- Additional reporting Surf Lifesaving New Zealand
Medals
Black Fins:
Gold - Ocean Woman Relay - Danielle McKenzie, Olivia Corrin, Olivia Eaton, Natalie Peat
Gold - Ocean Man Relay - Max Beattie, Cory Taylor, Kodi Harman, Chris Dawson
Gold - Male Board - Cory Taylor
Silver - Female Ski - Danielle McKenzie
Silver - Female Beach Flags - Olivia Eaton
Silver – Male Beach Flags - Kodi Harman
Silver - Mixed Ocean Lifesaver Relay - Carina Doyle, Max Beattie, Danielle McKenzie, Kodi Harman
Silver - Ocean Woman - Danielle McKenzie
Silver - Ocean Man - Cory Taylor
Junior Black Fins:
Gold - 4x25m Manikin Relay - Lucy Makaea, Macy Burns, Claudia Kelly, Tessa Bradley
Gold - 4x25m Manikin Relay - Lochlainn O'Connor, Zac Reid, Oscar Williams, Declan Dempster
Gold - 100m Manikin Carry with Fins -Lochlainn O'Connor
Gold - 50m Manikin Carry - Lochlainn O'Connor
Gold - 4x25m Manikin Relays – NZ team
Silver - 4x50m Medley Relay - Lucy Makaea, Macy Burns, Sasha Reid, Tessa Bradley
Silver - 100m Manikin Carry with Fins - Oscar Williams
Bronze - 50m Manikin Carry - Macy Burns
Bronze - 200m Super Lifesaver - Zac Reid
Records
New Zealand Record – Lochlainn O'Connor: 100m Manikin Carry with Fins 47.98
New Zealand Record – Macy Burns: 50m Manikin Carry, 37.53
New Zealand Record - Lochlainn O'Connor: 50m Manikin Carry, 31.18
