FishEthoBase:
Short Profiles and FishEthoScore
➜ For full text including Scoring Logic, please click on the PDF download button top right of this window.
The main intent of FishEthoBase is to improve fish welfare by 1) assessing if and to which extent the practices in farming of a fish species satisfy the needs and behaviour patterns observed in the wild, and 2) providing recommendations for improvement to practitioners, based mainly on ethological findings from scientific research.
FishEthoBase is focussing on behaviour
Fish welfare depends on 3 types of factors: physiological, behavioural, and mental factors. In the FishEthoBase short profiles, we focus on 10 core criteria for behaviour. For other factors and criteria, we recommend
Short profile:
A sharp assessment of the welfare state and potential of a species
With the short profiles, we pursue two goals:
FishEthoScore as an indicator for practice and science
The 3 dimensions are assessed and scored separately in each of the 10 criteria and summarised in the FishEthoScore (see page 3, Scoring Logic), indicating the overall extents of Likelihood, Potential and Certainty of a species’ welfare.
For more detailed recommendations please go to our “Recommendations” page (a part of our full profiles) of the species in question, if available. Unfortunately however, for most of the species assessed in a short profile, we are not yet able to provide a full profile as it demands much more work.
The FishEthoScore of the various species may help to decide on which species one should best concentrate research, development, and investments in order to put the industry in a position to positively answer the upcoming fish welfare demands.
➜ Continue reading by clicking on the PDF download button top right of this window.
Short profile rationale | (download as pdf) |
Criteria | Li | Po | Ce | |
---|---|---|---|---|
1 | Home range | |||
2 | Depth range | |||
3 | Migration | |||
4 | Reproduction | |||
5 | Aggregation | ? | ? | |
6 | Aggression | ? | ? | |
7 | Substrate | |||
8 | Stress | |||
9 | Malformation | ? | ||
10 | Slaughter | ? | ||
FishEthoScore | 0 | 2 | 3 |
Li = Likelihood that the individuals of the species experience welfare under minimal farming conditions | ||||||||||||||
Po = Potential overall potential of the individuals of the species to experience welfare under improved farming conditions | ||||||||||||||
Ce = Certainty of our findings in Likelihood and Potential | ||||||||||||||
? | / | |||||||||||||
High | Medium | Low | Unclear | No findings | ||||||||||
FishEthoScore = Sum of criteria scoring "High" (max. 10) |
Lutjanus argentimaculatus is a snapper species native to the tropical and subtropical Indo-West Pacific from Samoa to East Africa and from Ryukyu Island (Japan) to Australia. It has been introduced in the Mediterranean Sea through the Suez canal (although it is not established there yet) and is found in the Aegean sea (Turkey) and near Lebanon and Greece. It is commercially demanded in Asia for its food quality and popular in Australia for recreational fishing. L. argentimaculatus is a long-lived species of up to 57+ years migrating to estuaries and freshwater habitats as juveniles and returning offshore to mature, spawn, and spend the rest of its life (except occasional visits to estuaries). There is high variability in depth range and life history (migration, reproduction) depending on latitude/climate. Most research has focused on migrations, natural and induced reproduction, and dietary needs. Further research is needed to determine natural behaviours (such as social and sexual behaviour), natural home range, aggression/territoriality in the wild, effects of handling and confinement on health and welfare, malformation rates, and slaughter protocols. In farms, L. argentimaculatus is usually cultured for 7-13 months. Therefore, due to late maturity in this species, most individuals are juveniles at harvesting time. Larvae are either collected from the wild or purchased from stocks. Due to the adults’ need to migrate for spawning, rearing individuals to become spawners is not recommended unless migration options are available.
Note: The age class "Adults" for farming conditions refers to large juveniles and young adults due to farmers estimating age class by size rather than by maturity status.
L |
Likelihood | M |
Potential | M |
Certainty |
LARVAE: WILD: no data found yet. FARM: larval tanks: 2-5 t in 1,000 m2 hatchery area [1]; fibreglass tanks: 400-500 L [2] [3]; conical concrete tanks: 3 t [2] [3].
JUVENILES: WILD: site fidelity in estuaries [4] [5]. FARM: net cages in ponds: 25 m2 or 100 m2 (5 x 5 m or 10 x 10 m) [1], 24 m2 (4 x 6 m) [6], 6.3 m2 (2.5 x 2.5 m) [7].
ADULTS: WILD: mostly offshore [8] [4] [9], but also found in estuaries [10]. Further research needed for specific ranges. FARM: flow-through concrete tanks: 150 t or 60.8 m2 (7.8 x 7.8 m) [2]; concrete ponds: 3,000 t [11].
SPAWNERS: WILD: no data found yet. FARM: circular concrete tanks: 4 m diameter [2]; floating net cages: 6 m diameter [12].
L |
Likelihood | L |
Potential | H |
Certainty |
LARVAE: WILD and FARM: no data found yet.
JUVENILES: WILD: 1.5-6 m, mainly 5-6 m in Australia [5] or <1.5 m in South Africa [13]. FARM: net cages of 1 m depth [6] in ≥1.0 m [1] or of 2 m depth in ≥2.5 m ponds [7]; flow-through concrete tanks (for JUVENILES to become SPAWNERS): 2.0 m [2].
ADULTS: WILD: 40-260 m [14] [15] [16], but also at 5-8 m [17] or 9-13 m [18]. FARM: no data found yet.
SPAWNERS: WILD: relatively deep offshore waters [4] and in reef lagoons and outer reef slopes (in Palau) [8]. Further research needed for specific depths. FARM: circular concrete tanks: 1.5 m [2]; concrete ponds: 3 m [11]; floating net cages: ≥5 m [12].
L |
Likelihood | M |
Potential | M |
Certainty |
CATADROMOUS [5].
LARVAE: WILD: offshore [4]. FARM: 0-21 days old: higher survival at 16 ppt salinity [19], but also reared at 32 [20] and 35 ppt [3]; >21 days old: 16-40 ppt [19]. For details of holding systems ➝ crit. 1.
JUVENILES: WILD: migration from offshore towards the coast and into estuaries and freshwater habitats in spring-summer depending on latitude [21]-[4] [22]. Mainly site fidelity [4] [23] or moving within 1 km in estuaries and freshwater habitats [4]; some move mean 4.3-10 km [5] [24]; rarely: inter-riverine (up to 85 km) [4]. Overnight migration to mangrove habitat during high tides for foraging purposes [24]. Migrate offshore to mature, the timing dependent on latitude or ecological conditions [21]-[4] [4] [23] [25]. FARM: salinity: 16-40 ppt [22]. For details of holding systems ➝ crit. 1 and 2.
ADULTS: WILD: offshore, occasional trips to the coast and into estuaries at 324-430 mm or 3-11 years of age [4]. FARM: for details of holding systems ➝ crit. 1.
SPAWNERS: WILD: 40-50 km offshore [4]. FARM: 100 m from the shore [12]; salinity: 25-36 [12], 30-32 ppt [2]. For details of holding systems ➝ crit. 1 and 2.
L |
Likelihood | H |
Potential | H |
Certainty |
WILD: mature from 7-8+ years on [25] [4], but also 1-3+ years depending on latitude [23]. Spawn in spring-autumn with peak in summer or year round depending on latitude and ecological conditions [21]-[4] [26] [4] [23]. Sex ratio: average 1 male:1.18 females (monthly variations) [9]. Spawning activity peaks at 14-18 days into the lunar month (in Palau) [8]. FARM: spawn at 5-7 years [12]. Natural spawning usually occurred 23:00-00:00 [11] or 02:00-04:00, 3 days before or after the last quarter and newmoon phases with a sex ration of 1 female per 1.07-1.13 males [12]. Successful induced spawning using luteinizing hormone-releasing hormone analogue or human chorionic gonadotropin [12]. Sex ratio for induced spawning: 1 female:2 males [12]. Higher hatching, percentage of normal larvae, and cumulative egg to larval survival rate in natural spawning compared to induced spawing [12]. Monthly rematuration of cage-reared broodstock during 5-6 consecutive months [27].
? |
Likelihood | ? |
Potential | L |
Certainty |
LARVAE and FRY: WILD: no data found yet. FARM: LARVAE: 5-16.4 [11] or 30 [3] IND/L; FRY (2.5-12 cm): 40-48 [7], 100-150 or 150-200 IND/m3 [1] [28].
JUVENILES: WILD: no data found yet. FARM: FINGERLINGS (≥20 g): ponds: 5,000 IND/ha; net cages: 5 IND/m3 [1] [29], but also 29 IND/m3 [6].
ADULTS: WILD: at 9-13 m depth, shoals of 5-30 individuals [18] or more [4]; solitary [18] or in groups around coral reef [4]. FARM: no data found yet.
SPAWNERS: WILD: no data found yet. FARM: 12-22 IND/cage (85 m3) [12]; 50-150 individuals in hatchery area of 1,000 m2 with several tanks [1].
? |
Likelihood | ? |
Potential | L |
Certainty |
LARVAE: WILD: no data found yet. FARM: cannibalistic behaviour (chasing and biting other's eyes and fins) from about 26 days of hatching, when over 25 mm [3] [11] [1].
JUVENILES: WILD: no data found yet. FARM: no data found yet.
ADULTS: WILD: no data found yet. FARM: no data found yet.
SPAWNERS: WILD: no data found yet. FARM: no data found yet.
L |
Likelihood | H |
Potential | H |
Certainty |
LARVAE: WILD: PELAGIC [4], offshore [4] and in coastal lagoons and estuaries [30]. FARM: PELAGIC [2]. For details of holding systems ➝ crit. 1.
JUVENILES: WILD: mostly rocks (<10 cm), snags (>10 cm) [4] [22], indurated sand [5], sandy habitats [22], but also rock reefs, soft sediments in estuaries [5], seagrasses [5] [22], mangroves [4] [23] [22], coral reefs and seaweed beds [23], bivalve shelves [22], tree roots [4] [22], aquatic macrophytes, artificial rock structures, under undercut banks or overhanging vegetation [4], or in pneumatophores of the mangrove Sonneratia griffithii and prop roots [31]. FARM: featureless tanks [30], coastal net cages, and ponds [3] [1]. The use of shelters and size grading are important to prevent sibling cannibalism and to produce uniformly-sized fingerlings [1]. Black net ribbons over cages and piled PVC pipes at the bottom of the cage as shelter for the fish [28]. Cages covered with old or used nets, coconut fronds or nipa shingles to protect the stock from direct sunlight and predator birds [28]. Light should be provided at night in cages and pens to attract zooplanktons [32]. LAB: tanks with rocks or snags increased growth and weight compared to featureless tanks and tanks with plastic strings simulating seagrass [30].
ADULTS: WILD: reef habitat and deeper offshore waters [4]. FARM: for details of holding systems ➝ crit. 1.
SPAWNERS: WILD: no data found yet. FARM: for details of holding systems ➝ crit. 1 and 2.
L |
Likelihood | M |
Potential | L |
Certainty |
LARVAE: no data found yet.
JUVENILES: stressed by repeated handling [30].
ADULTS: no data found yet.
SPAWNERS: no data found yet.
? |
Likelihood | M |
Potential | L |
Certainty |
LARVAE: no data found yet.
JUVENILES: lordosis (3.8%) and brachyospondyliosis (1.1%) [11]. 60 mg AMP (L-ascorbyl-2-monophosphate-Mg) per kg of dry diet is recommended, otherwise soft body (AMP-free diet) or kidney and liver degeneration and low hematocrite levels (AMP > 180 mg/kg of dry diet) [20].
ADULTS: no data found yet.
? |
Likelihood | M |
Potential | L |
Certainty |
Common slaughter method: no stunning method available [33] [34]. High-standard slaughter method: ikijime recommended in recreational fishing [35]. Further research needed to confirm for farming conditions.
All age classes: WILD: carnivorous [37] [24] [22]. FARM: no data found yet.