Researchers in Germany and New Zealand are studying the potential of farming seaweed in high-energy, exposed environments

Seaweed farms in New Zealand tend to be constrained to coastal, nearshore environments, but these areas are becoming congested, increasing the risk of user conflict. Climate change, meanwhile, is impacting coastal areas and bringing its own set of challenges, making it all the more important for seaweed farming to be suitable for exposed, high-energy sites. New Zealand’s government is also hoping to unlock the potential of open ocean farming, to diversify aquaculture outputs and produce new, high-value products.

Amidst this backdrop, the Open Ocean Aquaculture team at the Cawthron Institute, New Zealand’s largest independent science organisation based in Nelson, is leading a research programme to explore the possibility of situating bivalve and seaweed farms in the open ocean. Known as Ngā Punga o te Moana (Anchors of the Sea), the programme is running for five years (2021–2026) and is aiming to deliver the necessary knowledge and technology to scale-up bivalve and seaweed farming in the open ocean. Among its key outputs are the design of farming structures, the use of advanced data science and modelling capabilities to understand the open ocean environment, and studies in bivalve and seaweed biology and physiology to discover species with the most potential to be farmed in exposed environments.

“When it comes to seaweed, New Zealand has over a thousand species, but we know little about the majority and some have barely been named,” Dr Kevin Heasman, leader of the Ngā Punga o te Moana programme, told WF. “However, the prospect of them providing nutraceuticals, pharmaceuticals, alternatives to oil-based products or food is huge. We are creating a structure that can grow a number of species and is adaptable and flexible to those species, so we are not reinventing the wheel every time we want to grow something. We are also looking to find out what conditions work best for seaweed and to what extent the structure can tolerate exposed conditions.”