Increased barnacle growth this season

Recent industry insights have highlighted a significant increase in barnacle growth in some parts of New Zealand, with marine organisations describing this as part of a wider “barnacle boom”.

Warmer-than-average sea temperatures over the 2025–26 summer have created favourable conditions for marine growth, accelerating the breeding cycle of barnacles. At the same time, changes to antifouling coatings in recent years mean some products may be less effective under higher fouling pressure.

Industry reports indicate that, in some cases, vessels have experienced barnacle growth within weeks of antifouling application, highlighting the unusually challenging conditions this season.

There have also been wider environmental signals across the upper North Island, including a two-year closure on the harvesting of intertidal species – such as barnacles – in parts of the Hauraki Gulf from March 2026, aimed at supporting ecosystem recovery.

While we have not seen widespread issues reported across our marinas, we wanted to share this information as a general heads-up for berth holders.

We recommend:

·       Regularly inspecting your hull, especially if your vessel has been stationary for extended periods

·       Scheduling hull cleaning or maintenance as needed

·       Speaking with your marine service provider for advice on antifouling options best suited to current conditions

We will continue to monitor industry guidance and share updates as needed.