Aquaculture and take home marine conservation messages

Question 1

Aquaculture - what it is

Answer 1

• Farming fish spp and other marine animals
• Accounts for ~50% of supplies of aquatic animals
• Grows hugely every year
• Largely FW but growth to marine spp
• At global scale and can massively increase yield for many groups

Question 2

Costs of aquaculture

Answer 2

• Supply fish with food - sometimes has to be other fish
• Nutrient/organic enrichment of waters
• Introduction of alien spp
• Pesticides in water course can cause disease
• Competition with other stake-holders for resources
• Habitat destruction - often somewhere in tropics (mangroves etc.)

Question 3

Solutions to aquaculture problems

Answer 3

Similar to wild fisheries…
•Top-down regulations enforcing best practice
•Reducing reliance on wild fish-derived feed
•Community-driven management
•Ecosystem approach

Question 4

Positives of marine conservation

Answer 4

• Marine extinctions remain scarce
• Most of the megafauna - its not too late
• Potential for large scale restoration - re-wilding

Question 5

Warnings to thinking conservation recovers exploitation…

Answer 5

•Conservation measures don’t agree guarantee return to previous conditions - hard to reverse newly established ecological conditions
-Baltic Sea changing from cod-dominant, to sprat-dominant
•In 25 over-exploited populations - 3 fully recovered, 10 showed no recovery in 15yrs
•No recovery of iconic Grand Banks cod fishery because…
-other fisheries still operate and catch code
-behavioural - young fish can’t find spewing grounds
-predation
-displacement by other spp
-CC - cod like cold water

Question 6

Multiple impacts effecting populations

Answer 6

• Recovery is maximised when multiple impacts are reduced (habitat destruction and overexploitation)
• Solving fisheries crisis won’t solve climate change
• Problems are 99% political, importance of using knowledge we have now with sociologists and economists