Fisheries 4 AquaCulture Flashcards
Overview
1- not new 2- recent trends 3- salmonida 4 costs / cons 5 advances (cod) 6. Prospects
Salmonids? (4)
Brown trout
Rainbow trout
Kind salmon
Atlantic salmon
- history of aquaculture
Not new has been done for centuries
Before light touch- semi natural conditions
Common carp was introduced To Europe from Asia by the Romans’
History of aquaculture
Carp detail
Carp were stocked as food fish in monastery ponds in Britain during Middle Ages
Has ancient roots in China and Far East where has been developed In parallel with agriculture
History of aquaculture
What can we learn?
Ecological principles of nutrient cycling and high feed conversion efficiency can be seen in Asian practices
- ecosystem approach principles?
Can they be applied to modern aquaculture?
- Aquaculture recent trends
Since how long?
Regional patterns? (3)
Already major player
Since 1940/ has spread dramatically whilst marine catches have flatlined
Europe vs Asia (faster rate in Asia)
Uk sites in 2014 (Jennings et al)
Can see marine fish and shellfish and freshwater aquaculture occurring throughout uk
PATCHY - particularly concentrated in Asia
In Europe not yet fully exploited (global fishing n contrast is homogenous around the world)
Note huge demand yet wild stocks under threat (omega 3)
Why is aquaculture useful?
What are salmonids?
Targets single spp no bycatch
Salmonids were amongst first intensively farmed fish (salmon and trout at large scale)
Salmonids 1
brown trout
Latin name ?
Native? £?
Economically important sport fishes globally
Native to freshwater and coastal ecosystems
Salmo trutta
Salmo trutta and stock enhancement
What is it and con?
We know brown trout well
Habitablt and spawning time known
Trout eggs can be purchased commercially most rivers are ‘enhanced’ with stock fish
We can tinker prorceases to maximise yield
Ie nutrient tanks and aerated water flow - increases recruitment from egg stage upwards
But
Could threaten gen diversify
Salmo trutta threaten gen diversity more detail
Wild brown trout come in100s of locally adapted distinct morphs
May actually represent spp flock rather than taxonomic entity
Townsend brown trout paper
Townsend 2003
Brown trout has been introduced to areas beyond natural range ie NZ
Where it is rapidly replacing the galaxif fishes
Brown trout is invasive to what and where
Galaxiid fish
NZ
Threats to gen div
Brown trout
Hybrid?
Beyond single app gen threat
Could hybridise
Brown trout x American brook trout
Different genera yet can still hubridise
Brown trout can hybridise with what to make tier trout in n america?
American brook trout
Brown trout overview (4)
Importance
Stock enhancement
Invasive
Tiger trout hybridisation
Rainbow trout overvieww 3
Importance
Mechanisation
Patents and selective breeding
Rainbow trout
Importance?
Most commonly farmed spp
Fishing and FOOD
Native to USA but introduced to many freshwater ie in UK rivers
Moving from hunters gathering towards farming of fish ( we manipulate its biology to maximise yield)
Rainbow trout
Mechanisation?
Automated
Trout sorter- size selection for harvest
Rainbow trout
Patents and selective breeding?
Selective breeding has produced fast growing strains more gen homogenous than wild pops
These can even be awarded trademarks for particular genes (patent genetic makeup)
Rainbow trout Latin
O mykiss
King salmon
Game?
Wild vs hatchery?
One of most intensively farmed group
Two genera
Both in recreational fisheries and aquaculture
Artificial fish are related to ENHAnce stock in game fisheries when recruitment is low ie in UK
BUT con?
Genetic homogenisation
Wild sleek
Hatchery higher fat content
Names
Wild?
Hatcher?
Wild coho salmon
Hatchery Hen coho salmon
Atlantic salmon Latin name
Salmo salar
Atlantic salmon
- life cycle?
- farming overall
- £££?
Marine phase in life cycle
Farming is growing concern increases growth in Scotland since 1980s
Scottish economic report
Important for ecotourism ie fly fishing and food Rural economy (especially where tasking has collapsed)
In Scotland is mult million pound industry
Overall cons of aquaculture
Threaten genetic integrity of locally adapted populations - ie female escaping and posing big problem
Risk of exotic diseases and parasites ie introduced to native pops
Pollution - uneaten fish pellet eutrophication
Not ecologically sound - contain undesirable fish spp caught elsewhere
Attracts other predators
Trade off
What do we mean by that
Aquaculture can alleviate pressure but also has own problems so needs to be balanced
Real life
Gen diversity problem
Eutro problem
New England salmon hatcheries
So many fry released that 500 salmon had genetic characteristics of wild salmon and this threaded within species biodiversity
Scotland eutrophication
Concern in many areas as effluents altering the surrounding marine ecosystem in some Scottish fish farms are leading to algal blooms
Why are farmed fish vulnerable T.I diseases (4)
What is done because of this that is controversial?
Using what
Kept at high densities
Genetically similar to one another
Bred selectively To grow fast and hug rather than resistance to disease
Uneaten food pellets can encourage pathogen outbreaks
Note many farms thus engage in active vaccination programs
Ie aquajector gun
Vaccination by?
Aquajector vaccine gun
Aquaculture real life disease example case study
Fish lice
Fish Luce can reach epidemic proportions rapidly in cramped conditions on fish farms
Major threat and global transport network increases risk of fish infection( fish live travel with them)
Result
Many previously clean wild fish pops now infected
Ie problem for sport fisheries
Escapees or wild fish trout may introduce lice to resident pops
Cost of fish lice problem and when
2017 global lice outbreak
Prices crashed to half value
Problem now global
Farming attracts other predators detail
Such as?
Example and tensions?
Piscivirous birds
Otters
Mink
Example: cormorants
Have been colonising inland waters in UK over last two decades and this has led to great resentment among many fish farmers
Otter numbers also rising ( dif opinions between conservationists and fish farmers)
What is another ethical aspect of aquaculture debate?
Clue fat
Wild salmon Lean low fat content
Farmed have higher fat content
Trade off
Public wild fishery managers and aquacukturists have different viewpoints
Dissecting shows
So much fat on organs that have to clean away shows how dramatic physiology change is
Recent advances in cod farming?
Overview
First developed
Opens ocean aquaculture project
University of New Hampshire open ocean aquaculture projects - mooring and cage system
2009 Norway brood stock
Recent advances in cod farming
First developed in Newfoundland in 1996
Works well as marine app are delicate and small and cannot be manipulated as readily yet brown trout is pretty good
What is the 2006 opean ocean aquaculture project?
Harvested first crop of Atlantic cod farmed in opean ocean 6 miles off coast
Dramatic change - scale up - eliminates eutrophication - open sea
Approached to cod were built on successful reading programs for other spp (ie flounder halibut and haddock)
Now numerous commercial ventures in traditional Atlantic cod fishing grounds
What is the university of New Hampshire open ocean aquaculture projects ?
What is the mooring and cage system?
Farming by remote control
Subversive containers
In areas prone to storm and bad weather
‘Holy grail ‘ of fish farming
Theoretical qu
Can you read cod from gen then harvest then form fertile next gen?
Where?
Yes
In Norway 2009
Produces brood stock from farmed cod
Norway 2009 what happened ?
From cradle to grave
Self contained population and example of scale
Now the population cycle can be closed within a farm
How was the Norway 2009 farmed cod was enabled to close the loop? - what techniques?
Enormous tanks with liquid
Food tanks for young juveniles including a itinerary and other marine plankton to feed them
Via remote sensor dispatches food at controlled rates
By computer with high resolution levels
Study systems and info feeding back into optimisation - what does this mean?
Fish are raised slowly from cages to avoid damaging their internal organs
Huge volumes of data are collected at all stages of their life to optimise yield and efficiency
Ie specific time of day to feed them
scientific theory —> into commercial practice
Commercial cod farming now underway in n America and Norway
- Prospects
Overview
5
- Alleviate pressure?
- Apply eco principles to improve sustainability
- Dif fish eating lower
- Non food stocks
- future demand increase
Prospects
1 alleviate pressure?
Capture fisheries flatlining
Aquaculture can alleviate pressure
Already seeing hunter gatherer shift to farming
Prospects
2 applying ecological principles to improve sustainability?
Eating large piscivores ( ecologically inefficient as rearing tigers for food)
This is unsustainable
Target Lower trophies levels to reach food security needs —> feeding down?
Prospects
- Feeding down in practice? An example
Particularly species that don’t eat smaller fish
Example: freshwater catfish farming in USA
Catfish is raised on SOYA
Prospects
4 non food stocks
What is project seahorse ?
Aquaculture can relive pressure on spp used in medicinal or aquarium trade
Project sea horse
Seahorse breeding and rearing programmes now being developed commercially
At Hawkes bay seahorse Farm > 50 000 searhorses are bred for the aquarium and medical trade
Prospects
- Future demands
Fisheries provide 16-19% if human animal protein consumption
1bn people rely on fish as main protein source
Rising demand will HAVE to be supplied with aquaculture ( only viable route) but costs and benefits must be weighed
Finally
Opinions and priorities?
Member states and ranking marine?
Member states have same pattern of concern
Pollution then little then CC
Fisheries are NOT high up in concern list when asked to rank concerns
Immediacy and urgency of the problem is not being addressed
Wider - example of invasive Scotland
2017 recent
Pawning if invasive
River ness
Actually breeding with escapes farmed fish from Russia and this is a huge threat of Scottish economy
