Aquaculture Flashcards
What types of aquaculture are we seeing?
Mariculture - in situ aquaculture (usually means marine aquaculture)
Aquaculture has been historically polyculture, but is now predominantly mono-culture. Starting to see a shift back to polyculture.
What are the types of intedgrated aquaculture?
IMTA - Simulate an ecosystem - control / reproduce an ecosystem. Basically non-existent at industry level.
Direct integration - no further input from humans. (on a slope - cows at top of the field ect)
Indirect integration - taking energy physically and moving it (manure)
Almost all moden day aquaculture is indirectly integrated.
What classsic terrestrial farming problems are reduced or absent?
Greenhouse gasses, human disease hosting, eutropication
Physiologically much closer to farm animals than fish.
1.2 kg feed to 1 kg salmon. 5.9 feed to 1 kg beef, but animals are much closer in sync to the enviroment.
How does land and water use affect why we do aquculture?
Land use
- Almost every person on the planet lives near water
- 7 Billion people today, 8.1 by 2025, 9.6 by 2050 (we need to find 75 million tons more fish, i.e. ~2x current production)
- Agricultural land was 0.44 ha person-1 since 1960, now 0.25 ha person-1 >50 % live within 3 km of surface freshwater ~80 % live within 100 km of the sea
Water use
- ~70 % of all available freshwater is used for agriculture
- Today this is 7, 130 km3, by 2050 this will be 13, 500 km3
- Is this a problem? - will need more freshwater than is availible
Why do aquaculture - physiological dmeand.
Physiological demand
- Historically we have always produced more protein than we need, by 2030 we will be deficient
- Today aquaculture accounts for about ~50 % of global ‘fish’ production, by 2030 this is expected to be 63 %
- Fisheries and aquaculture provide 4.3 billion people with 15 % of their average annual protein intake (~20% global animal protein)
- (Apparently) important to LEDC’s, because of the breadth of nutrients not found elsewhere
- 30 countries where fish are > 1/3 total animal protein, 22 of these are LEDC
However
- Protein derived from plants (beans, peas, nuts etc.) far outweighs protein derived from all animal sources combined (total from ‘fish’ ~6.5 %)
- Actually no studies showing that more fish consumption = better nutritional status in LEDC’s
- Health studies which apply to LEDC diets do not necessarily apply to MEDC diets and vice-versa
Why do aqucaulture - economic demand.
Economic demand
- Aquatic products (capture and aquaculture) collectively account for the most traded food commodity on the planet (not including coffee?)
- Value of all ‘fish’ in 2012 was $129 billion (~45 % would have been aquaculture)
- Generally recognised that aquaculture alleviates poverty, but evidence for links between national-level impacts and house-hold level impacts are minimal (and probably more than a bit dodgy)
- Aquaculture facilities often have a fierce class divide, money doesn’t filter down. No labour buffer, only the wealthy can take it up.
- For every one aquaculture job there are two more in supporting industries
- Huge disparities in actual numbers reportedly employed in aquaculture (24 million, Bush et al 2013; 100 million, Handisyde et al 2017)
- Social dynamics are a major factor in the uptake of aquaculture
- Wealth, status, community, education, gender, tradition, etc.
Why do aqaculture fisheries stagnating.
oGlobal fish supply has increased from 12.7 kg person-1 year-1 in 1961 to
21.4 kg person-1 year-1 in 2010
oFrom 1960-1990 this was almost all from fisheries, since 1990 (especially since 2000) almost all from aquaculture (the “Blue Revolution”)
oGlobally aquaculture has grown 9.5 % per year since 1980
Why do aquaculture - food security
More stable, more controllable, year-round production compared to fishing
Why is aquaculture more stable than terrestrial agriculture?
The amount of species gives a buffer to the problems caused by disease. (Swine flu ect)
But debated as to whether it fixes or moves the problem due to the relatedness to capture fish.
Why do we aquaculture - all the reasons.
- Good feed to produce ratio
- Terrestrial farming problems reduced or absent
- Freshwater availbility
- Physiological demand
- economic demand
- Fisheries stagnating and food and fish consumption rising
Where do we aquaculture - China
- Largest producer, processor, consumer, and exporter of ‘fish’
- 1/3 of all ‘fish’ are produced in China, >70 % from aquaculture equating to about half the total value of aquaculture
- Aquaculture production has quadrupled since 1990, but space use has only doubled - efficiency
- Known for erroneous data collection and reporting; “NEI” accounts for 31 % of total marine capture.
- Massive reliance on fishmeal for feed (coming later); unclear if China adds to global food production or depletes it.
Where do we aquaculture - Europe
- Highest producers are Norway, Spain, France, UK (8 % total European production, but still imported 80 % of all fish in 2012)
- Spain and France is mainly bivalves
- Stagnated at around 1.2 % (maybe less) since 2000
Why do we not do as much aquacultute in Europe?
Shortage of space or public image
Where we can aquaculture is taken up by other things
Traditional methods of aquaculture -
- Introduce fish to rice paddies - common in literature but not actually that common - hard to keep fish and rice happy.
- more typical to cover whole rice pady to aquaculture - now illegal in China.
- Ponds
- more extensive than intensive, about food not money.
- Pig pen over aquaculture
- not really very popular
- Grass carp, come in and graze on feilds.
- Traditional polyculture.
- Principle hundreds of years old in China, japan and Korea
- Not stimulating an ecosystem on a wider scale but may have been popular.
- Seaweed culture - common.
Modern methods, how do we aquaculture?
- Basic containment - in situ (ponds, mariculture)
- Have to be positioned in deep water with good water flow, putting aquaculture in the same place as shipping lanes.
- French / Spain mussel spat - culture them anywhere in the world and sold as French mussels.
- Intensive, Monoculture, Varying levels of control
- Full control; ex-situ, often indoors in tanks, total determination of abiotic factors
- *
Compare traditional vs moden aquaculture requirements.
- High-density, Circulation, aeration, treatment, additives, feed, Monoculture, Larvae bought from hatcheries
- As a pose to Low-density, Few controls, no feed, Some poly-culture, Larvae caught from the sea
What are the aims of aquaculture in LEDC’s?
oAlthough production dominated by LEDC’s, export is to MEDC’s – shifts focus from food to money
oLEDC policy is focussed on max money, and (sometimes) minimal ecological damage.
What is and isn’t often considered when carrying out aquacultur in LEDC’s?
oNo concern for diversity in production – health problems, vulnerability in the operations and in the market
oNo concern for social factors, e.g. class division
oNo concern for sustainability
May consider ecological damage, things need to be kept clean to reproduce, and can be damaging to tourism industry. Exporting to MEDC means it has to abide by export standards.
Moden methods- the dependance on feed
Aquaculture as a sector is totally dependent on feed
- 50-80 % of costs from feed
- 100 % of salmon farms use feed, 83 % of marine shrimp, even 38 % of carp
- > 2/3 of finfish and crustacean aquaculture is dependent on feed
Feed comes from
- Capture fisheries; ‘trash’ fish, anchovy, sardine, herring, menhaden – at least 71 species in China (probably?); largest importer of fishmeal, huge imports and even fishing rights from other fisheries (Peru, Chile, USA, Russia)
- Terrestrial farming, arable and livestock; mostly waste products which is good, but absorption efficiency is low and the quality of the fish can be reduced
- In 2012 ~70 % of aquaculture activity was supplemented by crop-based feeds
- Most of the other 30% (i.e. 23 %) is bivalves (not fed), much of the rest will be algae
- Overlap between ingredients for terrestrial feeds and aquaculture feeds, but only 4 % goes to aquaculture
- Massive push right now to end the dependency on fish-based feed (next lecture)
Martyn paper - problems ranking
Jones et al 2015
- Formed 25 key problems from suggestion from practitioners and scientists, and then asked the same people to rank the issues.
- UK industry’s and scientist, but most of them are global issues, at the wide scale.
- Single biggest problem is knowledge exchange.
- 5 are environmental and policy and 5 feed and disease
- Very few came down to husbandry.
- Scientists were more reserved than practitioners.
- Last question that basically says ‘why is it that when we eat fish we get more benefit than if we ground that fish up and made a pill.’ Practitioner score lower as it would put them out of business.
What is pellet feed?
oPellet-feed production increased from 7.6 million tonnes in 1995, to 27.1 million tonnes in 2007. Projected to be >70 million tonnes by 2020
oMost pellet feeds are based on “trash” fish
oWidely regarded in the literature as the single most pressing concern
