Midterm #3

• In 2014, human consumption of seafood surpassed the amount of seafood caught by capture fisheries for human consumption. More than half the world's production of that year came from aquaculture.
• In 2021, human consumption of seafood surpassed the total amount of seafood caught by capture fisheries.
• Due to the human consumption of seafood surpassing the amount of seafood caught by capture fisheries, there has been a rapid increase in aquaculture of many forms of seafood.
• The term "fish" in aquaculture refers to finfish.
• The term "shellfish" in aquaculture refers to invertebrates - primarily molluscs and crustaceans.
• The term "plants" in aquaculture refers to marine vegetation (e.g., seaweed).
• Differences between aquaculture and capture fisheries:

  • Intervention - enhancing the stock (e.g., feeding)
  • Ownership (people own the stock)
• Overlap between aquaculture and capture fisheries:

  • Production of seed stock - for enhancement (juvenile production, then released into the wild)
  • Enhancing of the environment (e.g., artificial reefs) - enhances fisheries = intervention
  • On growing of mature animals - capture wild animals (unsustainable)
• Seed stock: juvenile organisms
• Agriculture began 10000-12000 years ago.
• Earlier instance of aquaculture began 2500 years ago with the farming of carp in China.
• Due to the more recent development of aquaculture, there is very few domesticated breeds, meaning wild species are still being farmed.
• Some farmed species may appear similar to their wild counterparts, but display a lot of genetic selection.
• Blue revolution: the increase in production of seafood.
• Promotional reasons for aquaculture:

  • Reduce impact on fisheries
  • Increase food production
  • Development of rural areas
  • Increase jobs and income
• Areas of aquaculture development:

  • Methods to raise commercially imported or threatened species (for human consumption or help species populations)
  • Development and enhancing genetic stocks (e.g., faster growth)
  • New sustainable species (low on the food chain, disease free, low maintenance, lower environmental impact)
• Aquaculture species account for less than 10% of animal protein consumed.
• Order of quantity of farmed species (most -> least):

  • Fish
  • Plants (large increase recently)
  • Mollusks (bivalves)
  • Crustaceans
• Some aquaculture species are more valuable relative to their weight.
• Most common types of fish farmed:

  1. Common carp
  2. Tilapia species
  3. Salmonids (e.g., salmon, rainbow trout)
  4. Channel catfish
• Carp and Tilapia species are herbivorous fish.
• Salmonids and Catfish are carnivorous fish.
• Despite carp production being the highest, they are not as valuable as salmonids.
• Carnivorous fish are high value and primarily produced in developed countries. Lower value herbivorous/omnivorous fish are primarily produced in developing countries.
• Asia is the world's leading producer of seafood (China in particular).
• Most aquaculture takes place in developing countries with carp production dominating the market, although tilapia production is rising and countries are beginning to expand into shrimp and crabs.
• China is such a large producer of seafood that its aquaculture production has surpassed its capture fishery.
• In most developed countries, the most aquaculture development tends to surround high intensity stock (i.e., animals high in the food chain that require a lot of food and maintenance).
• British Columbia is Canada's leader in aquaculture with Atlantic salmon being Canada's prime aquaculture species.
• In the future, BC may not produce as much Atlantic salmon due to legislation preventing the farming of Atlantic salmon in the Pacific ocean. In turn, Atlantic provinces may increase their production of Atlantic salmon.
• This image demonstrates a pond aquaculture set up.

  
• Pond aquaculture is the farming of fish from specially build bodies of water.
• Pond aquaculture can occur above or below ground and in fresh or brackish water.
• Pond aquaculture works best with several small, long, and narrow ponds for ease of access to stock for feeding or harvesting, limited waste of land, minimizing loss in case of disease, and ease of pond maintenance.
• Small ponds in pond aquaculture have better circulation, which allows for less water treatment.
• Rectangular ponds allow for the best use of space in pond aquaculture and allow for easier access to the center of the pond, although ponds can be adapted to fit the surrounding landscape.
• Pond aquaculture ponds tend to be less than 2 m deep to encourage phytoplankton growth and ensure thermoclines don't form (easier to mix).
• Requirements for pond aquaculture:

  • Good water supply
  • Ability to maintain pond and plankton source
  • Relatively impermeable soil or plastic lining
  • Gravity drainage
  • Inputs of water
  • Water filtration
  • Outflows
• This image displays a raceway and tank aquaculture set up.

  
• Raceway and tank aquaculture is the 2nd most common type of aquaculture system with salmonids being the most common fish farmed in this set up.