If it still seems strange to think about fish growing on farms, it shouldn’t be.
Aquaculture has been the fastest growing food sector in the world for decades, and people now eat more farmed fish than wild fish.
The industry has had to grow. The demand for seafood is increasing and will continue to increase. But the oceans are giving up all they can: Wild fish production has remained stable since about 1990.
Fish farming and shellfish production. They typically emit much less greenhouse gas emissions than production of beef and other animal proteinsbut aquaculture can still cause serious environmental problems.
And as it has grown, the problems of large-scale agriculture have grown with it. Many are problems similar to those faced by massive chicken, hog and cattle operations. Farms and their waste can degrade and contaminate nearby ecosystems, diseases can spread quickly among crowded fish, and collecting food for animals can cause distant environmental problems.
Facing harsh criticism and stricter regulations (and eager to meet demand), fish farmers are trying new ways to boost production and minimize damage.
Aquaculture villages in Indonesia
Indonesia’s rise to become the world’s third largest producer of farmed seafood caused destruction on nearby coasts. The mangroves, which protect the coast and act as nurseries for a large number of aquatic species, were uprooted.
Basins contaminated with untreated waste. The massive fish die-off shook local economies.
“Every year we face the same problem, especially when the seasons change,” said Jono, a farmer who, like many Indonesians, only uses one name. “We had so many dead fish.”
Jono received training as part of a broader Indonesian government plan that will establish more than 100 aquaculture “villages” across the country designed to reduce the impact of fish farming and expand production.
He has learned how to better prevent and treat diseases, new feeding techniques, better pond construction and proper waste disposal.
“Before we used to harvest every eight or nine months, now it can be every four or five months,” he said.
China takes fish farming abroad
China, by far the world’s largest aquaculture producer, is also trying to reduce the environmental impacts of fish farming.
One way: take it out to sea, where currents can deliver clean water and debris can dissipate quickly.
Two kilometers (1.2 miles) off the coast of the northeastern Chinese city of Yantai, three 80-meter (260-foot) wide round cages lie beneath the sea surface.
Bream, Korean rockfish and other fish wiggle and swim in netting made from a lightweight, durable plastic that can withstand extreme weather conditions and keep barnacles at bay.
The facility’s platform is equipped with a monitoring system that constantly detects water temperature, water quality and oxygen levels, said Zhang Zhuangzhi, who is in charge of fish farming at Shandong Ocean Harvest Corporation, which runs the operation.
Until now, costs and technical challenges have held back widespread adoption.
A salmon fishery in a Florida warehouse
At a warehouse near Miami, large indoor tanks are designed to mimic the salmon’s natural environment by setting the right temperature, the right salinity, and the right lighting.
The idea: grow salmon indoors to reduce exposure to parasites, warming waters and algae blooms that threaten fish farmed in open waters near the coast, and in turn reduce the impact of fish on the coast.
The technology “eliminates some of the disadvantages that nature could have,” said Damien Claire, chief sales and marketing director at Atlantic Sapphire, the parent company of Bluehouse Salmon.
Claire said the company does not need to vaccinate or medicate its salmon and has reduced the fish mortality rate to around 3%, much less than the industry average of 20%.
Raising fish in an indoor, strictly controlled environment has also led to other benefits, he said.
The company produces about 3 million salmon a year and hopes to eventually produce 65 million.
It’s a promising model, but it’s not easy to follow because the system relies on a rare feature of the groundwater near the warehouse location: Salmon need both fresh and salt water, and both are found nearby.
French fly factory
When farmed fish are fed wild-caught fish, such as sardines and anchovies, one of the main benefits of fish farms – less stress on ocean ecosystems – can evaporate.
At France-based Innovafeed, protein-rich black soldier flies are being bred as a food alternative.
The company chose the fly for three main reasons: it doesn’t get sick, it eats almost anything, and it has a short life cycle that allows it to be raised and harvested quickly.
“There is a joke that the larvae of the black soldier fly eat everything except concrete and steel,” said Nizar El Alami, commercial director of Innovafeed.
The company’s fly protein feeds salmon, bream, shrimp and other species to food producers throughout Europe, the Americas and Southeast Asia, according to Alex Diana, product manager at Innovafeed. It now has two factories and is planning 10 more by 2030 that will produce insect proteins for fish, chicken and even pets.
“We are trying to reproduce what happens in nature, but on an industrial scale,” he said. “We are trying to minimize the impact of the food chain on the planet’s resources.”