As you may have experienced, there has been an abnormal growth of barnacles in certain regions of Australia and New Zealand, particularly in hotspots like the Bay of Islands in New Zealand.
We wanted to share some expert insights about this issue based on information from AkzoNobel, a leading manufacturer of antifouling paints.
Why This Is Happening
The recent barnacle infestations are occurring due to:
- Warmer than normal water temperatures
- Environmental changes causing population explosions of barnacle larvae
- Localised conditions creating ideal breeding environments
Importantly, this problem affects all types and brands of antifouling paint. Even the best antifouling products can be overwhelmed when there are extremely high levels of barnacle spawn in the water.
How Antifouling Works (And Why It’s Being Overwhelmed)
Copper biocide in antifouling paint works by deterring barnacle larvae from attaching to your hull. However, if a barnacle does manage to attach and molt into adult form, it becomes resistant to copper and can grow undisturbed.
What Boaters Are Experiencing
According to AkzoNobel’s research:
- The same antifouling product may work perfectly in areas near the problem zones
- Vessels that remove barnacles and leave affected areas generally perform normally
- Boats launched or cleaned during cooler water temperatures tend to perform better
- Vessels remaining in affected areas are likely to be re-infested if conditions persist
- Changing antifouling brands while staying in the same area typically doesn’t solve the problem
- Polishing and ablative (softer) antifouling types seem to perform slightly better than harder types
Recommendations for Boat Owners
- Talk with locals to identify barnacle hotspots and avoid these areas when possible
- Check underwater areas of your hull monthly if you’re in or near affected regions
- Remove barnacles while they’re small and easier to displace
- Clean underwater areas before leaving any region to prevent spreading
- Re-check two weeks after leaving to ensure you haven’t brought hitchhikers
- Be aware that barnacles left for months can grow to 10-15mm, making removal more difficult
If you must remain in an affected area, perform regular hull checks, especially during summer months. The good news is that the problem typically subsides when water temperatures cool down.
Should you have any questions about this issue or the appropriate antifouling products for your vessel, please feel free to contact Harry.
Happy boating!
Marine Detailing Company
Phone: 0211758174