Dragonfly Data Science Director and Fisheries scientist, Dr Philipp Neubauer, has recently returned from auditing one of the largest abalone fisheries in the world based in Tasmania—and there are lessons for Aotearoa's pāua fisheries.
The Marine Stewardship Council (MSC) sets the international standard for best practices in fisheries management to reduce overfishing to support fishery sustainability and healthier oceans, which is essential for abalone fisheries increasingly affected by climate change.
As an auditor for bio.inspecta, Philipp assessed the Tasmanian Abalone Fishery against the first of the three principles required to obtain an MSC certification: fishery assessment and management.
“My job was to review how the fishery assesses and manage stock levels, ensuring they use sustainable practices to prevent overfishing as required by the MSC," says Philipp.
For many fisheries, obtaining an MSC certification is no small feat. The process of building and auditing a fishery's sustainability practices typically lasts at least a year and a half.
A changing environment
Climate change is continually shifting the stock productivity and reference points, making it increasingly difficult to define and measure fishery performance against formalised benchmarks, such as those from the MSC.
“Tasmania has faced a number of marine heatwave events that have severely impacted stretches of the coastline, directly affecting abalone,” says Philipp.
As abalone are ectotherms, they rely on their external environment to regulate their body temperature. Rising water temperature can lead to changes in their metabolism, stunt their growth, and reduce reproduction.
“Extreme short-term changes in water temperature cause abrupt changes in the production potential either by stopping the abalone from growing because the water is too warm or even killing the juveniles,” says Philipp.
“The Tasmanian Abalone Fishery has had to adjust its management practices to respond to these weather patterns, which is something we can expect to see more of in New Zealand pāua fisheries, as climate change continues to cause ocean temperatures to fluctuate more severely.”
Bringing international insights back home
In New Zealand, there have been areas with fairly steady and productive pāua fisheries that are no longer thriving, which fishery scientists believe is likely due to the degree of temperature changes those pāua populations experienced.
“Pāua can only survive some level of change; they simply cannot cope in stagnant waters with really high temperatures for a long period of time,” says Philipp.
“There are lessons to be learned from the Tasmanian experience that undoubtedly apply in New Zealand. I’ve learned which aspects within the fishery’s management systems and its harvest strategies are important in the context of changing productivity and climate impacts.”
In Aotearoa, pāua fisheries are thought to be the country’s most vulnerable fisheries to climate change. Therefore, it’s important to understand international best practice to ensure New Zealand can enact management systems that encourage the growth and sustainability of its pāua fisheries.