New Zealand have a chance to close the gap on series leaders Australia in their home SailGP event on the country's South Island over the weekend.

The event is the ninth of 13 legs in the series and, with around 22,000 tickets sold, is being billed as the largest ticketed sailing event in history.

Many more spectators are expected to watch the two-day event from boats around the course, raising concerns among conservationists for the endangered Hector's dolphin which lives in and around Lyttelton Harbour and currently is in its calving season.

The SailGP series is in its fourth year and involves 10 teams racing identical high-tech foiling catamarans that can reach speeds of around 50 knots (92 km/h).

There are three regattas after Christchurch in Bermuda, Halifax and New York before the three leading teams compete in July's San Francisco finale.

Each event involves six fleet races before a final, the winner of which is the event champion. The champion is awarded 10 points on the overall series standings, the second team nine points and so on down to one point for 10th place.

Australia have 66 points, eight clear of second-place New Zealand. Denmark (52) are next, followed by Spain (48) and France, Britain and the United States all on 45. Canada (38), in eighth place, won the Lyttelton event last year from the hosts.

New Zealand driver Peter Burling returns after missing the last leg of the series in Sydney while on paternity leave. Nathan Outteridge drove the Kiwi boat into second place in Burling's absence but will drive for last-placed Switzerland this weekend.

"If you look at the forecast, it's going to be a step up breeze-wise from last year," said Burling, who drove NZ to wins in his last two events before his break.

"It's definitely been an interesting season but (we're) looking forward to our home event now and trying to ramp up into the grand final.

"Going for the hat-trick for myself. It's going to be an absolutely awesome weekend."

Australia's win in Sydney was their first event victory of 2024, though it's consistency has taken them to the top of the series standings.

"It was important for us as a team," Australia driver Tom Slingsby said of the Sydney victory.

"We were sailing so well ... it was just getting a bit frustrating not being able to put it together in that final race. For us to get our first win in Australia was just the perfect fairytale.

"We've got that off our back and now we can start focusing on the end of the season and the grand final."