Aquaculture is expanding rapidly. Market research analysts estimate that by 2025, the global fish farming market will reach $376.48B by 2025, remarkable growth from $271.60 billion in 2018. While much of the expansion of aquaculture in recent years comes from an increase in freshwater fish farms, the marine aquaculture segment is projected to have the highest CAGR: 4.8% from 2018 to 2025.
While aquaculture offers the promise of a more sustainable food source, there are still grave environmental concerns that come with expanding the use of fish farms — especially those farms based in the ocean. As the market grows, aquaculture proponents will need tools like ocean buoys and sensors to responsibly select, establish, and maintain aquaculture sites further offshore. Here’s how ocean buoys can improve the safe growth of marine aquaculture.
Aquaculture is a large industry made up of many different segments, one of which is “mariculture” — aquaculture that involves the use of seawater. Mariculture operations are either set up onshore next to the ocean, or offshore, depending on the types of organisms being bred. Molluscs, prawn, and other shellfish are suitable organisms for onshore sea water mariculture operations.
Offshore aquaculture involves the use of open-net pen and cage systems — mesh cages between six and 60 cubic feet that are installed in the ocean with fish inside. There are immediate environmental risks to using these types of set-ups. Predatory fish get tangled in the nets, and the high concentration of fish within the pens can lead to a high concentration of waste, chemicals, and diseases filtering into nearby ecosystems.
Nevertheless, aquaculture continues to expand worldwide — in part because the demand for aquatic plants has grown considerably. “Seaweed, which can grow rapidly and efficiently, provides plant-based proteins and shows promise as a source of biofuel to replace fossil fuel,” reported The Guardian. “Its ability to absorb carbon dioxide, nitrogen and phosphorus also make it a living vacuum to clean up polluting chemicals discharged by farms, factories and wastewater treatment plants.”
Marine aquaculture has many benefits beyond the potential to provide a new source of green energy. Marine aquaculture creates jobs: former and current fishermen are using aquaculture to support and supplement their livelihood. This leads to more resilient coastal communities and provides global trade opportunities.
Likewise, aquaculture is an effective way to meet the demand for seafood. Shellfish, salmon, and bait fish can all be farmed to increase the food supply without decimating wild populations of fish and mollusks. The FAO estimates that aquaculture accounts for 50% of the world’s fish used for food.
Lastly, aquaculture installations are flexible, and can be adapted to different coastal regions without needing too many modifications. Marine aquaculture tanks can be constructed on the seafloor or left hanging in columns. Onshore tanks and cages can also host salt-water organisms, while freshwater lakes, rivers, and artificial ponds are also available.
Despite the many benefits of aquaculture, there are still environmental and logistical obstacles that need to be overcome to support the safe and sustainable growth of this sector. Most urgently, near-shore fish farms cause a range of environmental issues.
A report by The Marine Aquaculture Task Force found that near-shore aquaculture simply isn’t a great option. “Environmental effects from aquaculture include water pollution, introduction of nonnative species, genetic effects on wild populations of fish and shellfish from escapes of farmed animals or their gametes, and concerns about the increasing use of wild forage fish for aquaculture feeds,” said the report. “Historically, culture of marine species has been done in situ in coastal waters. However, with the dramatic increase in coastal development in the United States in recent decades, clean water and suitable sites for coastal aquaculture are at a premium.”
One possible solution to these challenges is to move marine aquaculture installations further offshore. Open-ocean aquaculture benefits from stronger surface currents and sub currents, as well as deeper waters that can dilute and wash away waste and pollution. They’re also less of an eye-sore for shoreline property developers.
While offshore aquaculture farms do not cause the same environmental chaos, they still face some logistical challenges — which is where ocean buoys can make all the difference.
Perhaps the biggest benefits to using buoys in marine aquaculture is site selection and optimization. Technology like Sofar Ocean’s Smart Mooring can help set up and maintain offshore marine aquaculture operations.
Smart Mooring offers multiple sensor configurations to measure a range of data, including:
With this data, farmers can choose sites where there’s sufficient current and depth to mitigate fish farm pollution. Sites can be selected to avoid “superchills” — extreme cold ocean water temperatures that can kill fish. Once operational, sensors can collect whatever data the farmers need to monitor offshore operations. For instance, farmers can create a more efficient feeding schedule that factors in currents and sub-surface water properties.
Crucially, the Spotter buoy gives aquaculture farmers a way to collect weather data — a new piece of information, given that farmers historically have only had access to water parameters. Weather data can provide better understanding of the work area during the design phase of the offshore aquaculture structure. More importantly, weather data can protect the health and safety of offshore staff. The ability to read buoy data and decide whether or not to send a vessel with staff based on real-time conditions is not only safer but also more cost-effective.
Aspecto Marine, a Norweigan aquaculture company, is using the spotter to stay on budget at their offshore operation.
“With Spotter, we have a tool to provide important real-time weather and underwater data to every farmer in Norway. It’s dashboard and API provides a platform for sharing weather information with other farmers in the community. To get this kind of information today (waves, wind, temperature, oxygen) would take a lot of time and a big budget. We believe that providing the tools to make this type of data widely available will make a huge difference for the industry,” said Aspecto Marine founder Carl Theimann.
Buoys can help advance the expansion of offshore marine aquaculture in a way that’s environmentally-responsible, cost-effective, and safe. By collecting data on surface currents, water quality, and sub-surface conditions, buoys can contribute to a more sustainable source of food for populations around the world.