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John's Snapper

Lutjanus johnii

Lutjanus johnii (John's Snapper)
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Distribution
Distribution map: Lutjanus johnii (John's Snapper)




Profile status
Dossier:
not provided by us yet
WelfareCheck:
F (2020-12-16)
Advice:
not provided by us yet
Taxonomy
Order:
Actinopterygii
Class:
Perciformes
Family:
Lutjanidae
Source:
Ethograms
In the wild:
not investigated by us yet
Farm/lab:
not investigated by us yet
Catch/lab:
not investigated by us yet
Habitat
Temperature:
F20.9-32 °C
Photoperiod:
no data found yet
Substrate:
Fyes
Growth
Length:
not investigated by us yet
Weight:
not investigated by us yet
Maturity:
F1.7-8 years
Malformations:
no data found yet
Swimming
Home range:
F100 ha
Depth:
F1.6-80 m
Migration:
Famphidromous
Activity type:
no data found yet
Reproduction
Nest building:
Fno
Courtship:
no data found yet
Mating type:
no data found yet
Brood care:
Fno
Social behaviour
Aggregation:
Fschool
Organisation:
not investigated by us yet
Aggression:
Finsufficient data
Handling
Stress | farm:
Fyes
Slaughter | farm:
Fno
Stress | catch:
not investigated by us yet
Slaughter | catch:
not investigated by us yet
Commercial concerns
Frequency | farm:
F4,637 t/year
Methods | farm:
Fvarying
Frequency | catch:
not investigated by us yet
Methods | catch:
not investigated by us yet

Farming remarks

Lutjanus johnii is a snapper species native to the Indo-West Pacific. It inhabits estuaries from the Fiji Islands to East Africa and from Australia to Ryukyu Islands. However, two different species with the same morphology might be considered to be L. johnii, one of them inhabiting the Straits of Malaca, Thailand, Australia, and China, and the other one living also in China as well as in India. It is cultured in Singapore, Malaysia, Australia, and Pakistan and valued for recreational fishing in both Australia and Malaysia, where it is overfished and vulnerable to climate change.

In the wild, L. johnii can live up to at least 28 years. In farms, JUVENILES attain market size (600-800 g) in 6-8 months, so they do not reach adulthood unless they are kept as broodstock. Natural spawning in captivity has not been achieved. Spawning after artificial manipulation is possible, but many farms still obtain FINGERLINGS from natural catches locally or more usually imported. Collection of SPAWNERS in the wild is not recommended because L. johnii is highly susceptible to barotrauma when caught from depths greater than 10-15 metres. Field data on L. johnii are currently insufficient and should be augmented by inshore surveys and observation of natural behaviours in its habitat. Further research on reproduction is needed to ensure a closed life cycle and to avoid the decimation of the natural populations. Improvements in the farming conditions are needed in order to accommodate the migration needs of JUVENILES, and adding environmental enrichment into cages will certainly improve their welfare. L. johnii's welfare can also be improved by using farming systems that promote a natural habitat and behaviour of the species as well as by developing humane stunning and slaughtering methods.

For details see: WelfareCheck | farm (latest major release: 2020-12-16)

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