Embed Size (px)
Citation preview
FISH FARMINGThe right solution to
overfishing?
WHAT I WILL BE SHARING TODAY
1. The Overfishing Crisis
2. The Solution: Fish Farming – or is it?
3. The Dangers of Conventional Fish Farming
4. Making Fish Farming Safe and Environmental
THE PROBLEM
Increasing Demand
THE PROBLEM
Overfishing
Increasing Demand
THE PROBLEM
Fisheries
Collapse
Collapse of Atlantic cod stocks (East Coast of Newfoundland), 1992
Overfishing
Increasing Demand
THE LOGICAL SOLUTION: FISH FARMING
Fisheries
Collapse
Overfishing
Increasing Demand
Fish
Farming
THE LOGICAL SOLUTION: FISH FARMING
Fisheries
Collapse
Overfishing
Increasing Demand
Fish
Farming
More Serious Problems? Fish Farm in Thailand
TRENDS
PROBLEMS WITH THE SOLUTION
The Precautionary Principle
“In order to protect the environment, the
precautionary approach shall be widely
applied by States according to their
capabilities. Where there are threats of
serious or irreversible damage, lack of full
scientific certainty shall not be used as a
reason for postponing cost-effective
measures to prevent environmental
degradation.”
- Principle 15 of the Rio Declaration
DIFFERENTIATING FISH FARMING
•Open Water•Along rivers, lakes, seas, oceans
•Ultimately lead to the ocean
• Closed Water
•Ponds, tanks, closed lakes
• Intensive•Food from external sources
•Maximise yield
• Extensive
•Food from sources inherent to habitat
•Lower yield
•Other Methods?
PROBLEMS WITH OPEN WATER FISH FARMING
PROBLEMS WITHOPEN WATER FISH FARMING
Introduction of
non-native species Antibiotics,
Hormones
Fish Meal and Fish Oil
Fertilisers
Incubation of
local diseases
and parasites
New diseases and parasites
introduced to the environment
Fish Sewage: Uneaten food, waste
products, diseases and pathogens
GM Fish and non-native
species that escape
compete with native fish
PROBLEMS WITH OPEN WATER: POLLUTION
PROBLEMS WITHOPEN WATER:POLLUTION
• Fertilisers
• Nitrogen Compounds
Phosphorus Compounds
PROBLEMS WITHOPEN WATER:POLLUTION
• Fertilisers
• Nitrogen Compounds
Phosphorus Compounds
Eutrophication
PROBLEMSWITHOPEN WATER:POLLUTIONIncubation of
parasites and
disease
Caligus louse feeding on young sockeye salmon taken
from a fish farm
PROBLEMS WITHOPEN WATER:INVASION OFWILD HABITATS
18-month-old salmon, one genetically modified, the other not.
PROBLEMS WITH INTENSIVE FARMING
PROBLEMSWITHINTENSIVEFARMING
Trophic Levels
1 kg of tuna
= 10 kg of sardines, catfish
= 100 kg of tilapia, oysters
= 1000 kg of phytoplankton,
seaweed
ALTERNATIVES
IMTAIntegrated Multi-trophic
Aquaculture
• Modernised form of
polyculture
• Rearing marine organisms
from different trophic levels,
e.g.
• Salmon (carnivorous)
• Carp, Oysters
(herbivorous)
• Seaweed (autotrophs)
AQUAPONICSPlants utilize water filled with
nitrogen-rich fish waste for
their own growth, purifying
the water for the fish in the
process
Aquaponics with catfish
IN CONCLUSION Any Questions?
