Information
Version: B | 1.2 (2024-12-31)
- minor editorial changes (incl. correction of domestication level) plus new side note "Commercial relevance"
WelfareScore | farm
Condensed assessment of the species' likelihood and potential for good fish welfare in aquaculture, based on ethological findings for 10 crucial criteria.
- Li = Likelihood that the individuals of the species experience good welfare under minimal farming conditions
- Po = Potential of the individuals of the species to experience good welfare under high-standard farming conditions
- Ce = Certainty of our findings in Likelihood and Potential
WelfareScore = Sum of criteria scoring "High" (max. 10)
General remarks
Gadus morhua is one of the most important commercial fish species in Northern Europe and North America’s eastern coast. Cods stocks were heavily reduced during the 1980s, and today the fishery is very low compared to historical levels. Stock collapses increased the investments in cod aquaculture enterprises, both hatcheries and on-growing farms began to accelerate. Within a few years an annual production capacity in the order of 60 million JUVENILES and around 400 on-growing sites was built up in Norway alone. However, the financial market crisis in 2008 together with recovery of natural stocks decreased aquaculture production. Despite the big investment in cod aquaculture, the living conditions and the husbandry systems that maximise the welfare of this species are still to be defined, developed, and improved. This lack is quite incomprehensible given the background and the availability of research performed on this species. To optimise fish welfare of this species, improvements are mainly needed to meet home range and depth range needs, reproduction without manipulation, deformation rate, aggression, and stress reduction.
1 Home range
Many species traverse in a limited horizontal space (even if just for a certain period of time per year); the home range may be described as a species' understanding of its environment (i.e., its cognitive map) for the most important resources it needs access to.
What is the probability of providing the species' whole home range in captivity?
It is low for minimal and high-standard farming conditions. Our conclusion is based on a high amount of evidence.2 Depth range
Given the availability of resources (food, shelter) or the need to avoid predators, species spend their time within a certain depth range.
What is the probability of providing the species' whole depth range in captivity?
It is low for minimal and high-standard farming conditions. Our conclusion is based on a high amount of evidence.3 Migration
Some species undergo seasonal changes of environments for different purposes (feeding, spawning, etc.), and to move there, they migrate for more or less extensive distances.
What is the probability of providing farming conditions that are compatible with the migrating or habitat-changing behaviour of the species?
It is low for minimal and high-standard farming conditions. Our conclusion is based on a high amount of evidence.4 Reproduction
A species reproduces at a certain age, season, and sex ratio and possibly involving courtship rituals.
What is the probability of the species reproducing naturally in captivity without manipulation of these circumstances?
It is low for minimal and high-standard farming conditions. Our conclusion is based on a medium amount of evidence.5 Aggregation
Species differ in the way they co-exist with conspecifics or other species from being solitary to aggregating unstructured, casually roaming in shoals or closely coordinating in schools of varying densities.
What is the probability of providing farming conditions that are compatible with the aggregation behaviour of the species?
It is unclear for minimal farming conditions. It is high for high-standard farming conditions. Our conclusion is based on a medium amount of evidence.6 Aggression
There is a range of adverse reactions in species, spanning from being relatively indifferent towards others to defending valuable resources (e.g., food, territory, mates) to actively attacking opponents.
What is the probability of the species being non-aggressive and non-territorial in captivity?
It is low for minimal farming conditions. It is medium for high-standard farming conditions. Our conclusion is based on a medium amount of evidence.7 Substrate
Depending on where in the water column the species lives, it differs in interacting with or relying on various substrates for feeding or covering purposes (e.g., plants, rocks and stones, sand and mud, turbidity).
What is the probability of providing the species' substrate and shelter needs in captivity?
It is low for minimal farming conditions. It is medium for high-standard farming conditions. Our conclusion is based on a medium amount of evidence.8 Stress
Farming involves subjecting the species to diverse procedures (e.g., handling, air exposure, short-term confinement, short-term crowding, transport), sudden parameter changes or repeated disturbances (e.g., husbandry, size-grading).
What is the probability of the species not being stressed?
It is low for minimal farming conditions. It is medium for high-standard farming conditions. Our conclusion is based on a medium amount of evidence.9 Malformations
Deformities that – in contrast to diseases – are commonly irreversible may indicate sub-optimal rearing conditions (e.g., mechanical stress during hatching and rearing, environmental factors unless mentioned in crit. 3, aquatic pollutants, nutritional deficiencies) or a general incompatibility of the species with being farmed.
What is the probability of the species being malformed rarely?
It is low for minimal farming conditions. It is medium for high-standard farming conditions. Our conclusion is based on a medium amount of evidence.10 Slaughter
The cornerstone for a humane treatment is that slaughter a) immediately follows stunning (i.e., while the individual is unconscious), b) happens according to a clear and reproducible set of instructions verified under farming conditions, and c) avoids pain, suffering, and distress.
What is the probability of the species being slaughtered according to a humane slaughter protocol?
It is high for minimal and high-standard farming conditions. Our conclusion is based on a high amount of evidence.Side note: Domestication
Teletchea and Fontaine introduced 5 domestication levels illustrating how far species are from having their life cycle closed in captivity without wild input, how long they have been reared in captivity, and whether breeding programmes are in place.
What is the species’ domestication level?
DOMESTICATION LEVEL 552, fully domesticated.
Side note: Forage fish in the feed
450-1,000 milliard wild-caught fishes end up being processed into fish meal and fish oil each year which contributes to overfishing and represents enormous suffering. There is a broad range of feeding types within species reared in captivity.
To what degree may fish meal and fish oil based on forage fish be replaced by non-forage fishery components (e.g., poultry blood meal) or sustainable sources (e.g., soybean cake)?
All age classes: WILD: omnivorous 53. FARM: fish meal and fish oil may be partly* replaced by non-forage fishery components 54555657.
*partly = <51% – mostly = 51-99% – completely = 100%
Side note: Commercial relevance
How much is this species farmed annually?
900 t/year 1990-2019 amounting to estimated <1,000,000 IND/year 1990-2019 58.
Glossary
BENTHOPELAGIC = living and feeding near the bottom of a body of water, floating above the floor
DOMESTICATION LEVEL 5 = selective breeding programmes are used focusing on specific goals 52
FARM = setting in farming environment or under conditions simulating farming environment in terms of size of facility or number of individuals
IND = individuals
JUVENILES = fully developed but immature individuals
LAB = setting in laboratory environment
LARVAE = hatching to mouth opening
OCEANODROMOUS = living and migrating in the sea
PHOTOPERIOD = duration of daylight
SPAWNERS = adults during the spawning season; in farms: adults that are kept as broodstock
WILD = setting in the wild
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