Aquaculture Overview

Introduction to Aquaculture

• Aquaculture: Farming of fish, seafood, and aquatic plants in fresh or saltwater.
• Mariculture: Aquaculture focused on marine species (saltwater).
• Monoculture: Cultivating a single species at a time.
• Polyculture: Raising multiple species together (e.g. finfish, shellfish, algae, crustaceans).
• Fastest growing food sector globally, critical for food production:
  • Over 50% of aquatic foods consumed by humans are farmed (FAO, 2024).
  • Farmed fish is the most efficient source of animal protein.

Contributions of Aquaculture

• Feeding the World:
  • Commitment to sustainable practices for 20+ years.
  • Significant number of people depend on aquaculture for livelihoods (more than 100 million).
• Food Safety:
  • BAP certification indicates adherence to high environmental and safety standards.
• Nutritional Benefits:
  • Fish is a rich source of essential nutrients: protein, Vitamin D, calcium, and omega-3 fatty acids.
  • Omega-3 from fish is more effective than supplements for heart health (University of Pennsylvania).

Environmental Advantages of Aquaculture

• Lower greenhouse gas emissions compared to terrestrial livestock (e.g. 7x lower CO2 than cattle).
• Sustainability Practices:
  • Zero bycatch; no unintentional capture of non-target species.
  • Practices improve utility of rural communities economically.

Aquaculture Farming Methods

1. Hatchery to Natural Release:
   • Intensive farming where fish like salmon are raised in controlled environments and released into natural habitats.
2. Life Cycle Rearing:
   • Fish are reared in controlled conditions and also held in open-ocean cages.
3. Indoor Rearing:
   • Controlled growing environments (e.g. striped bass) with tank systems.
4. Pond-Based Farming:
   • Extensive practices with minimal environmental control (e.g. tilapia, carp).

Successful Aquaculture Practices in Canada

• Shellfish Farming:
  • Bivalves (oysters, mussels) thrive well due to filter-feeding mechanisms.
  • Involves rearing larvae to juveniles and then adults while avoiding the need for additional feeding.
• Mussel Culture:
  • Certified organic blue mussels are a significant product from Newfoundland.
• Oyster Cultivation:
  • Expanding due to the loss of natural reefs; takes 4-5 years to reach market size.
• Shrimp Culture:
  • Focuses on species like tiger prawn, but poses disease and environmental risks.

Concerns with Aquaculture

• Salmon Farming Issues:
  • Escape risks leading to wild stock displacement.
  • Potential disease transmission (e.g. sea lice, viral outbreaks).
• Environmental Impact:
  • Mangrove destruction for shrimp farms and pollution from accumulated waste.
  • Nutrient loading causing eutrophication in coastal waters.

Solutions and Innovations

• Land-Based Aquaculture:
  • Offers benefits such as reduced environmental contamination, disease control, but high costs involved.
• Integrated Multi-Trophic Aquaculture (IMTA):
  • Combines different species to optimize space and nutrient use (e.g. salmon, mussels, kelp system).
  • Still in development stages, particularly in Atlantic Canada.

Conclusion

• Aquaculture presents numerous opportunities to sustainably address food challenges while also raising concerns that need to be addressed through innovation and best practices.