Acipenser naccarii is a critically endangered species of the sturgeon family. It was probably driven to extinction in the wild due to overfishing and was preserved solely due to the efforts of regional governments and fish farms (one in Italy and the other in Spain) that started a reproduction programme. Nowadays its production efforts are divided between repopulation and caviar. A minor percentage is hybridised with Acipenser baerii for meat production. It is however surprising that almost no information on the biology of this species is available and therefore neither a clear assessment of its current welfare state nor potential for improvement is possible. Further research should be dedicated to all the criteria evaluated on the list below as well as the success of the repopulation effort.

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?

Likelihood

Potential

Certainty

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?

Likelihood

Potential

Certainty

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?

Likelihood

Potential

Certainty

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?

Likelihood

Potential

Certainty

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?

Likelihood

Potential

Certainty

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?

Likelihood

Potential

Certainty

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?

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Potential

Certainty

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?

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Certainty

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?

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Certainty

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?

Likelihood

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Certainty

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 4 20, level 5 being fully domesticated.

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: carnivorous 4. FARM: no replacement of fish meal and fish oil reported in literature.