Aquaculture problems

Nota:

• there are many problems with aquaculture at the moment stopping it from being a effective solution to the farming problem
• this is also to do with the dischord between what science deems as the most important and pressing problem then what industry and average people 

1. feeds

   Nota:

   • pellet feed production went from 7.6 million tonnes in 1995 to 27.1 in 2007 and then over 70 million tonnes 
   • most pellet feeds relie of waste from fishing industries which means they are still reliant of the fishing industry they are trying to replace - also dictated by climate change  seen as the most pressing thing in the litrrture 
   • fish are mainly taken from LEDCS like africa and south america which relie on fishing to feed and support thier populations 
   • many of the main industries like salmon carp and shrimp use 50% of all fishmeal but only account for 10% of the total production which waste 50-80% of the costs of aquaculture 
   1. solutions

      Nota:

      • there is a current push for plant-based feeds  - palmer ooil instead of fish oils and soya  - problem with absorption effieiciecy - achse et al 2013 - NGS are used to see how this will effect the physiological dynamics 
      • some feeds do come from wastes epecially that from china  unedible crops and livestock can be used by biaccumulation of contenminents and cross species pathogens can be an issue 
2. other additives
   1. medication

      Nota:

      • epecially a concern with antibiotics due to resisdents within pathogens then consumed by humans and horizontal gene transfers  probiotics 
   2. antifoulants
   3. Anaesthetics

      Nota:

      • historically problematic but improving from using clove oil and methanol 
   4. hormones and pigments
   5. gene modification
3. environmental interactions
   1. pollutions

      Nota:

      • 2/3 of feed is lost from phosphorus and nitrogen 
      1. organisms

         Nota:

         • faeces  ammonia waste  carapaces and scales  mortality  diseas and parasites  and the above from predators and epiphytes 
      2. husbandry

         Nota:

         • 75% of antibiotics are losted into the environment  copper and other metals end up in sludges from feed and antifoulents 
      3. Harmful Algae Blooms

         Nota:

         • hyproxia, eutrophication and bethic sludge are the result  autopollution is the problem with most things 
      4. norwegian salmon

         Nota:

         • in 1989 the salmon farms produced pollution equviellent to 2.7 million people they produced 150,000 tonnes now its a 1 million tonnesof fish  
         • the fish are kept in high tech offshore cages that can hold up to 1000 tonnes of fish 
   2. space used

      Nota:

      • deforestation for inland and estuarine fisheries 
      • habita loss from pens 
      • changes in sediment dynamics and water flow
      • competition for space in already crowded water ways  - fishing tourism, shipping, industrys and renewables  - impacts on aethetics of the area 
   3. pollution impacts

      Nota:

      • industrial pollution in medcs can cause mass mortalities 
   4. invasive species

      Nota:

      • this is a problem caused by all farming as 99% are introduced into the area 
      • the actual farm itself facilitates and causes the introduction of novel speceis 
   5. escape

      Nota:

      • problematic for both the industry due to lose and for biodiversity due to an influx of animals impacts are on a scale depending on the circumstance 
      1. atlantic salmon

         Nota:

         • 94% are maricultured when these escape as shown in scotland and norway the impact the natural population due to juveniles having reduced survival gentics and they bring pararsites and disease with them 
   6. predation

      Nota:

      • this is the main removal of stock this is mostly done by birds and the vunerable ones are bivalves 
      1. stress from near by predators
   7. climate change

      Nota:

      • there is actual very little studies done on this but its certain itll be a case by case basis 
      1. shifts in
         1. temperature
         2. rainfall
         3. storms
         4. ph
         5. salinity
         6. ocean circulation
         7. el nino
      2. interactions with
         1. captured fisheries
         2. husbandry practices
         3. species distribution
         4. market demands
4. Disease and parasites
   1. cultured organisms
      1. treatment
         1. consider

            Nota:

            • logistics  economics  environment  future proofing  poilcies 
      2. preknowlegde of relationship
      3. practices/solutions
         1. additives

            Nota:

            • antibiotics, probiotics, chemical treatments, vaccinations 
         2. zoning

            Nota:

            • limits transfer between farms 
         3. service species

            Nota:

            • cleaning wrasse
         4. culling/removing dead/infected animals
      4. bivavles

         Nota:

         • one of the main industries and are the most vunerable 
         • additives  - filter feeders so antibiotics are too dilute to have an effect  - they have no immunology to inject 
         • zoning - works for some but many are mobile pathogens 
         • no service species that can access soft tissue 
         • very hard to tell which are infected and which are dead 
         1. transition

            Nota:

            • the romans first started using Ostrea edulis however this is very suctible to disease and there have been serveral crashs in production 20, 70 and 90s  
            • we then used crossastrea agulata, butthe same problem happened again
            • the common one used today is c.gigas problems  - invasive and carrys on to be invasive  - infected with the herpesvirus  - large mortalitys in 2008 
      5. salmon

         Nota:

         • salmon are costinly effected by lice (copepods) that feed of tissue and mussels this cause secondary infection, stress, reduce swimming, reduce blood glucose and electorlyte levels, reduced haemoatocrisis, supression of the immune system 
         • farms are hotspots for lice which spill over into the wild poppulations 
         1. treatment

            Nota:

            • chemicals in feed  injections  - chemical baths
            • one treatment hardly ever works due to rise in antibiotic resistence - genomes fully sequenced to help developed drug 
            1. cleaning wrasse

               Nota:

               • labrus bergylta - 60 cm long  highly efficient  however the wrasse must be kept healthy - they will switch diet if removed  they are also taken from somewhere and can be over exploited 
   2. of humans

      Nota:

      • practicioners of aquaculture are more likely to get diseases, parasites and injury 
      • this is mostly ignored and mostly in LEDCs 
      • this is due to high injuries, exposure to warm, nutrient parasite filled water - with bad food prep and hygine 
      • leads to schistosomiasis is the second bigest economic loseafter malaria in the tropics and is highly ignored 
5. policy
   1. MEDCS

      Nota:

      • this is a very overly complicated sytem due to many governing bodies and getting a licinsing can take years 
      • for uk its the blue growth stragie and the common fisherie policy 
      1. policy makers

         Nota:

         • fisherie commeties  agriculture agencies  envrionmental agencies  vetenary regulators  food safty commisions  local level council 
      2. chemical additives are strictly contorlled
      3. multi species prohibited due to disease tranfer
      4. EIA

         Nota:

         • Environmental Impact Assessment - which is hugely complcated and if not impossible when more then one species is being grown 
   2. LEDCS

      Nota:

      • this is very money based  so very few policies if any on  - addtives  - water treatment  - animal welfare  - polyculture  - feeds  - working conditions 
6. Future direction
   1. offshore mariculture
      1. shallow and coastal dominated by seaweeds and bivavles
      2. doesnt suffer with as many problems
      3. its main problem is the money aspect, due to high technology needed

         Nota:

         • there are some ready to deploy on the market but these are hard to establish in both LEDCS and MEDCS 
   2. Integrated MultiTrophic Aquaculture

      Nota:

      • waste from one aquacultrue helping another on a diferent trophic level  dynamics between internal and exturnal set up 
      • massvie potentail varity in set ups and the useof algae and aquaponics 
      • there are huge advantages if you get this right 
      • all tested stragies have very good outcomes and results however no profitable one in MEDCS yet