Underwater farms vs. climate change - Ayana Elizabeth Johnson and Megan Davis

Summary

Seafood, a crucial protein source for 3 billion, faces overfishing with 33% of wild fisheries overexploited. Aquaculture, growing at 5.8% annually, presents both environmental challenges and sustainable opportunities. Traditional methods like net pens and coastal ponds contribute to pollution and disease, while innovative approaches like land-based farms and low-impact shellfish and seaweed farming offer solutions. These restorative methods not only combat climate change but also support coastal economies and sustainable diets with minimal carbon footprints.

Takeaways

• 🌍 Seafood is a crucial protein source for 3 billion people worldwide.
• 🐟 33% of wild fisheries are overfished, and 60% are fished at maximum capacity.
• 🦐 More than half of the seafood we consume is farmed through aquaculture.
• 📈 Aquaculture is one of the fastest-growing food industries, expanding 5.8% annually.
• 🐠 Common aquaculture methods include large net pens, which can lead to environmental issues like pollution and disease.
• 💊 Antibiotics used in aquaculture can contribute to environmental pollution and antibiotic resistance.
• 🌱 Coastal pond farming, like those for shrimp, can destroy ecosystems and spread disease.
• 🏞️ On-land farming in contained systems can help reduce pollution but still faces challenges like fishmeal sourcing.
• 🌿 Focusing on lower trophic level species like shellfish and seaweed can offer a more sustainable approach to aquaculture.
• 🌱 Seaweed and shellfish farming can improve water quality, combat climate change, and create habitats for other species.
• 🌱 A small-scale, distributed network of ocean farms could potentially feed the world sustainably.

Q & A

What is the significance of seafood as a source of protein and nutrition globally?

Seafood is a significant source of protein and nutrition for 3 billion people around the world, highlighting its importance in global diets.

What percentage of wild fisheries are currently overfished according to recent studies?

Recent studies show that 33% of wild fisheries are overfished, indicating a significant strain on natural fish populations.

What is the percentage of seafood that is not caught in the wild but grown through aquaculture?

Over half of the seafood we eat, including finfish, shellfish, seaweed, and algae, is not caught in the wild but is grown through aquaculture.

How fast is the aquaculture industry growing in terms of volume?

The aquaculture industry is expanding rapidly, with a growth rate of 5.8% in volume each year.

What are the common environmental issues associated with large net pen aquaculture?

Large net pen aquaculture is associated with environmental issues such as overcrowding, waste pollution, disease spread, and the use of antibiotics that can harm the local ecosystem.

How do escaped fish from net pen farms impact local ecosystems?

Escaped fish from net pen farms can compete for resources, weaken the local gene pool with captivity-adapted genes, and even become invasive species, disrupting local ecosystems.

What are the environmental consequences of man-made coastal ponds used for shrimp farming?

Man-made coastal ponds for shrimp farming can lead to pollution, disease spread, and the destruction of important ecosystems like mangroves and marshes.

How do land-based fish farming systems address the issue of water pollution?

Land-based fish farming systems, such as tanks and raceways, can recirculate and filter water to prevent pollution, addressing one of the major environmental concerns of aquaculture.

What is the role of fishmeal in aquaculture, and what are the challenges associated with it?

Fishmeal, made from about 10% of the global seafood catch, is used to feed carnivorous farmed fish. However, it contributes to overfishing and presents a challenge for sustainable aquaculture.

What alternative solutions are being explored to reduce the dependency on fishmeal in aquaculture?

Researchers are exploring alternative fish feeds made from insects and plant-based proteins to reduce the dependency on fishmeal and promote more sustainable aquaculture practices.

How can shellfish and seaweed farming contribute to a sustainable and regenerative ocean farming system?

Shellfish and seaweed farming can contribute to a sustainable system by not requiring feeding, naturally improving water quality, absorbing carbon through photosynthesis, and creating habitats for other species.

What is the potential of restorative ocean farming in terms of food production and its environmental impact?

Restorative ocean farming has the potential to produce substantial amounts of food with a low carbon footprint and can help combat climate change, reduce ocean acidification, and support coastal communities.