The ecological case of fish farms

This summer, tens of millions of salmon were cooked in California in their own natural habitat. Record heat and drought have reduced water flows and raised temperatures in streams and rivers across the state. Heat shock, along with the impacts of parasites and fungal burns that are fueled by warmer waters, have decimated wild salmon populations.

To stem the crisis, scientists literally went above and beyond, launching salmon over dams via pneumatic cannons and trucking millions of fish to the Pacific Ocean to bypass unlivable rivers. Meanwhile, with support from the Biden administration, policymakers and water managers have diverted precious water resources from farms and cities to stem mass salmon mortality. Even so, iconic salmon species such as the Chinook could be wiped out along the US West Coast as drought persists.

The extreme conservation measures are a stark reminder that America urgently needs bold federal legislation to mitigate climate change. But the salmon crisis sends another clear message: we need longer-term coping strategies, including a significant expansion of aquaculture in the United States; federal lawmakers, investors, consumers and even environmentalists all need to play a role.

As we develop fish farming, we must be extremely careful about creating an environmentally destructive feedlot industry in the ocean. Radical new advances in marine culture technologies and methods are correcting existing problems so that aquaculture can grow in a sustainable way.

Seafood is the only major source of protein mankind still harvests from the wild. Almost 90% of the world’s fish stocks are exploited or overexploited. Agriculture will exceed the volume of capture fisheries by 2024, according to estimates by the Food and Agriculture Organization of the United Nations. Recent economic analysis predicts that the global aquaculture market will exceed $245 billion by 2027, up from $180 billion today.

The potential for growth is particularly spectacular in the United States, which imports 90% of its seafood – more than two-thirds of which is farmed – but ranks 17th in the world for aquaculture production.

Here’s the caveat: For decades, aquaculture – and salmon farming in particular – has been a serious threat to wild fish and marine ecosystems rather than a necessary measure to protect them. To this day, salmon farms from Patagonia to Norway plague pristine marine ecosystems with parasites, pollution, runaway fish and disease, while depleting populations of wild fish like herring and sardines used as food. .

According to the UN, aquaculture could be the most sustainable method of producing protein on earth if done right. Farmed salmon is the most environmentally intensive form of aquaculture – more resource-intensive than farmed tilapia, catfish and cod, for example – but salmon is a frugal eater by comparison. to terrestrial animals. Fish generally need fewer calories because they are cold blooded and don’t have to heat up their bodies or build up layers of fat and fur to keep warm. They also don’t need energy to resist gravity or walk upright on all fours. While it takes nearly two pounds of feed to produce a pound of chicken, three for a pound of pork, and about seven for a pound of beef, it takes about a pound of feed to produce a pound of salmon. breeding.

Because salmon farming is also the most profitable form of aquaculture – an $18 billion global industry that is expected to nearly double by 2027 – technological advances in this area are influencing all other forms of fish farming. Where salmon farming goes, so does aquaculture, is the industry adage.

In the past decade alone, salmon farmers have halved the volume of wild fish used as animal feed and developed plant-based foods as alternatives; they have found ways to control pests with robotic and laser technologies that can eliminate the use of insecticides; they have introduced closed containment systems that can capture waste and prohibit escapes. The most promising innovation is actually thousands of years old – a practice known as “multi-tropical” aquaculture used by Chinese farmers around 500 BC that cultivates various underwater agricultural habitats with multiple species – algae, bivalves and finfish. It is the marine equivalent of regenerative agriculture practices.

Investors must support these innovations and environmentalists must update their case against aquaculture rather than blocking its growth, pressuring producers to modernize their practices and calling on lawmakers to effectively regulate the industry. .

In the United States, the Magnuson-Stevens Fishery Conservation and Management Act has done an exceptional job of managing and restoring coastal fisheries and has set an example around the world. We need such an ambitious policy to guide the growth of aquaculture – demanding the highest production and equipment standards, as proposed by the Aquaculture Stewardship Council, Seafood Watch and the World Wildlife Fund.

Wild seafood remains the main source of protein for nearly 4 billion people, mostly in developing countries. As climate pressures intensify, industrialized countries must quickly move away from catching wild fish, protecting these resources for the people who need them most. Aquaculture done right can help de-acidify the oceans and restore their health, supporting a climate-resilient food supply. America must take the lead in helping to ensure that a major expansion of aquaculture protects marine systems rather than destroying them.

This column does not necessarily reflect the opinion of the Editorial Board or of Bloomberg LP and its owners.

Amanda Little is a Bloomberg Opinion columnist. She’s a professor of journalism and science writing at Vanderbilt University, and the author of “The Fate of Food: What We’ll Eat in a Bigger, Hotter, Smarter World.”

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