Fisheries Disturbance

• 180 million tonnes in 2015 from aquaculture production
• capture productions in ocean starts to flatline as fish are overexploited
• largest amount of landings are in developing countries
• 17% of global animal protein comes from fish
• 3.2 billion people have 20% of their animal protein from fish
• 59.6 million people are employed in fisheries and aquaculture in 2016
• 4.6 million fishing fleets
• majority of fisheries are not mechanised
• there is a patchy distribution of fisheries and catch rates
• fish consumption decreases as GDP increases
• evolution of fisheries

  A) profits

  B) catches

  C) number of vessels

  D) fish abundance

  
• abundance of fish will decline overtime
• fishery collapse can lead to reduction of fish, number of vessels, catch rates, and profits
• if a fishery collapses, profits can become negative as more investment is put into the vessels and employment
• regional fisheries have been improving but not globally
• triple bottom line 


  defines successful fisheries as those which are ecologically sustainable and capable of generating sustainable positive net income and wealth
• sustainable fisheries must keep fish stock sustainable, local community is thriving, and minimal disturbance of the habitat
• maximum sustainable yield 


  the greatest amount of a natural resource that can be removed/harvested without jeopardizing the future resource
• fish mortality and recruitment/ harvesting need to be in balance
• relationship of fish 1

  A) age

  B) number of fish

  C) mortality

  
• relationship of fish 2

  A) age

  B) growth

  C) weight of fish

  
• recruitment of fish under low mortality

  A) spawners

  B) low fishing mortality

  C) recruits

  
• recruitment of fish under high mortality

  A) spawners

  B) high fishing mortality

  C) recruits

  
• more employment could mean less profit
• maximum economic yield


  catch that creates the largest difference between revenues and the cost of fishing
• MEY tends to be lower than the MSY
• fishing gear that comes into contact with the seabed has the highest bycatch rates
• longlines have high pelagic bycatch
• reducing impacts includes :

  limiting fishing efforts, catches, and spatial access, change in gear and design