A colleague drew my attention to a story in the Guardian. The subject was marine heatwaves in New Zealand. (The QR code on this page provides access to the article.)
Not only are marine heatwaves now more severe, but they are also happening more often. So much so, in the last decade we experienced them virtually every single year, with 2021-2022 the worst on record.
According to the Guardian article, some parts of New Zealand saw elevated water temperatures for up to 270 days per annum – by as much as four degrees Celcius.
Such radical changes to our marine environment have many negative effects. And these have been observed right around New Zealand’s coastline, from little blue penguins and other seabirds washing up dead from starvation on beaches in the Hauraki Gulf, Bay of Plenty and elsewhere, to hundreds of dying rays bream, a deep water fish, washing ashore on Otago beaches.
Fish farmers have suffered too, with NZ King Salmon, New Zealand’s largest salmon producer, losing hundreds of tonnes of salmon from their farms in the Marlborough Sounds in 2021-22. This has led to the company permanently shutting down some of its Marlborough operations.
Meanwhile, giant bull kelp forests and Fiordland’s sponges have been dying from heat stress, while forage fish – and the bird, mammal and fish species that prey on them – have shifted their distribution around our coasts. Some have disappeared from certain areas completely while others, including ‘northern’ species like snapper and kingfish, are turning up in surprising places like Fiordland, Stewart Island and Southland.
Other strange phenomena may also be linked to these heatwaves. The ‘milky flesh’ condition much reported in snapper from northern regions could be a side effect of warmer water. I have caught several fish afflicted with this unappetising, soft and mushy, milk-white flesh myself and seen many others caught.
For anyone who spends time on or in the water, what’s happening is certainly cause for concern. At the very least, we as boaters, divers and fishers can expect to see considerable divergence away from what was once considered normal.
Let’s hope that cooler El Niño conditions will bring a return to some sort of normality, at least for a time, but with the long-term warming trend apparently well entrenched, there’s undoubtedly more change coming to the seas around New Zealand.
On a more encouraging note, this magazine went to press just days before the Hutchwilco New Zealand Boat Show opened at ASB Showgrounds. After Covid disruptions, boat shows around the world are once again big business.
The Hutchwilco show came hard on the heels of the highly successful Auckland International Boat Show in March, itself returning after a three-year hiatus. That show found favour with exhibitors and patrons alike, attracting 13,500 visitors from around New Zealand and beyond who spent well over five and a half million dollars in the host region. Great for the local economy, the boating public, and the marine industry.
An Auckland institution, the Hutchwilco, with its focus on trailer boats, fishing tackle, marine equipment, services and accessories, should be bigger than ever. In our July issue I’m hoping we can report New Zealand boaties really got in behind it.
Happy Boating,
John Eichelsheim
Editor
