Aquatic food production systems

Natural capital is the stock of natural resources (living and non-living) that provides ecosystem services and economic benefits (for example oceans, lakes, rivers).

They provide food (fish/seafood) and regulate climate (heat and carbon storage), among other services like water purification and tourism.

Provisioning, regulating, supporting, and cultural ecosystem services.

MSY stands for maximum sustainable yield.

Provisioning services include fish and shellfish for food, seaweed, and freshwater supply.

Maximum sustainable yield is the largest catch that can be taken indefinitely without causing long-term population decline.

Fish stocks decline over time and may collapse if the breeding population becomes too small to recover.

Because fish populations can regenerate naturally through reproduction if harvesting remains at or below the regeneration rate.

If fish are harvested faster than they reproduce, populations can fall below a recovery threshold and collapse, making the resource effectively non-renewable.

Renewable does not equal infinite.

Capture fisheries are the harvesting of wild fish and other aquatic organisms from oceans, lakes, and rivers.

Catching wild fish (and other aquatic organisms).

Bycatch is non-target species caught accidentally during fishing, often discarded dead.

Overfishing and bycatch are major problems (also habitat destruction and IUU fishing).

Technologies like GPS, sonar, and large efficient nets increase catch efficiency, making it easier to remove fish faster than stocks can reproduce.

It can destroy seafloor habitats and increase bycatch, damaging ecosystems.

It can reduce food security and income for fishing communities, causing economic losses and job impacts.

Overfishing can cause stock collapse and disrupt food webs, including trophic cascades when key species (especially predators) are removed.

Illegal, unreported, and unregulated fishing avoids quotas and monitoring, increasing overfishing and undermining management.

Fish stocks are renewable natural capital, but unsustainable harvesting can degrade or collapse the resource.

Aquaculture is the farming of aquatic organisms such as fish, shellfish, and seaweed in controlled environments.

Fish farming (farming aquatic organisms).

Pro: reduces pressure on wild stocks. Con: can pollute water or spread disease if poorly managed.

It can reduce pressure on wild fish stocks and provide a reliable year-round supply of protein (also creates jobs).

Common disadvantages include water pollution from waste/chemicals, disease spread in crowded pens, and escapees that compete or breed with wild populations (also feed issues and habitat loss).

Salmon are carnivorous and often require fish meal/oil from wild fish, increasing pressure on capture fisheries.

Mangrove forests can be cleared to create shrimp farms, reducing coastal protection and biodiversity.

Herbivorous/omnivorous species (like tilapia/carp) need less fish meal/oil, so they put less pressure on wild fish used as feed.

Without good management it can cause pollution, disease, genetic impacts on wild stocks, and habitat damage, so sustainability depends on practices used.

Farming lower-trophic-level species is usually more sustainable.

Harvest must be less than or equal to regeneration so natural capital is maintained.

Sustainable fishing means harvesting fish at or below the regeneration rate so populations can be maintained long term (often linked to MSY).

Fishing quotas, marine protected areas (no-take zones), and closed seasons (also gear restrictions and certification).

Fisheries: quotas and MPAs (or closed seasons). Aquaculture: farm herbivorous species or use recirculating systems.

Because quotas and rules only work if based on stock data and if illegal overfishing is prevented through monitoring and penalties.

They restrict fishing in certain areas so populations can reproduce and recover, helping replenish surrounding fisheries via spillover.

Farming herbivorous species and using recirculating systems/filters reduce impacts (also IMTA and reduced antibiotic use).

MSY is the maximum catch that can be taken long term without causing population decline; catching above it is unsustainable.

Define sustainability and MSY, then give distinct strategies for capture fisheries and aquaculture, each with a brief “how it helps” explanation.

The MSC label is a consumer certification that helps identify seafood from more sustainably managed fisheries.