|Scientific Name:||Epinephelus chlorostigma|
|Species Authority:||(Valenciennes, 1828)|
Serranus areolatus subspecies japonicus Temminck & Schlegel, 1842
Serranus assabensis Giglioli, 1889
Serranus celebicus subspecies multipunctatus Kossman & Räuber, 1877
Serranus chlorostigma Valenciennes, 1828
Serranus geoffroyi Klunzinger, 1870
Serranus reevesii Richardson, 1846
|Taxonomic Notes:||Very similar to E. gabriellae and E. polylepis (likely to be confused); these two species replace E. chlorostigma in the north-west Indian Ocean including the Arabian Gulf.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Choat, J.H., Craig, M.T., Fennessy, S., Ferreira, B., Bertoncini, A.A., Robinson, J. & Rocha, L.|
|Reviewer(s):||Sadovy, Y. & Moss, K. (Grouper and Wrasse Red List Authority)|
Epinephelus chlorostigma is listed as a species of Least Concern since it is a widespread and relatively abundant species that is not known to be currently in decline. However, the species is one of the most common species in catch in a number of locales and should be monitored carefully and frequently as more information becomes available.
Epinephelus chlorostigma is an Indo-Pacific species that ranges from the Red Sea to Natal (South Africa), eastwards to the western Pacific (including Madagascar), north to southern Japan, and south to New Caledonia. Records from the Persian Gulf are apparently misidentifications of Epinephelus polylepis. Its presence has not been verified from the Comoros, on the continental shelf between Oman and Cambodia, Taiwan, Philippines, Indonesia, western Australia or Somalia.
Red Sea, Djibouti, Aden (Yemen), Oman (Groeneveld, unpub. data), Somalia (Darar 1994, Mann and Fielding 2000), Kenya, Tanzania, Mozambique, South Africa (KwaZulu-Natal), southwestern Madagascar (Myers distributional database 2006), east coast of Madagascar (A. Pages, Refrigepech Est. pers. comm.), Seychelles, Réunion, Mauritius (Myers distributional database 2006), Maldives, India, Indian islands (Andaman, Nicobars, Lakshadweep), Sri Lanka (Myers distributional database 2006), Thailand (East Burma Sea (distributional database 2006)), southern Vietnam, Korea, Indonesia/Malaysia (northern Sumatra, Malaysian peninsula, Sunda shelf, Bali), Western Australia, Papua New Guinea, New Caledonia and Vanuatu (Myers distributional database 2006), Samoa, southern Japan, Fiji, Taiwan (Myers distributional database 2006), China (Hong Kong). The distribution is from Heemstra and Randall (1993), unless otherwise stated.
Native:American Samoa (American Samoa); British Indian Ocean Territory; Cambodia; China; Comoros; Djibouti; Egypt; Eritrea; Fiji; India; Indonesia; Israel; Japan; Jordan; Kenya; Korea, Republic of; Madagascar; Maldives; Marshall Islands; Mauritius; Mayotte; Micronesia, Federated States of ; Mozambique; Myanmar; New Caledonia; Palau; Papua New Guinea; Réunion; Samoa; Saudi Arabia; Seychelles; Solomon Islands; Somalia; South Africa; Sri Lanka; Sudan; Taiwan, Province of China; Tanzania, United Republic of; Tonga; Tuvalu; Vanuatu; Viet Nam; Wallis and Futuna; Yemen
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Indian Ocean – western; Pacific – northwest; Pacific – western central
|Lower depth limit (metres):||280|
|Upper depth limit (metres):||4|
|Range Map:||Click here to open the map viewer and explore range.|
Epinephelus chlorostigma is an abundant species throughout its range.
The most common grouper caught off northern Somalia (Darar 1994), although few were seen in northern Somalia while diving on shallow (2 to 14 m) non-coral reefs in northern-eastern Somalia (Mann and Fielding 2000). Not reported in 130 shallow (et al. 1996, Pereira 2003). In shallow (9 to 13 m) fixed transect UVC surveys in the St Lucia and Maputaland Marine Reserves (northern KwaZulu-Natal, South Africa) between 1987 and 1992, Chater et al. (1995) recorded only one individual out of 43 groupers.
Moderately common (n=31 individuals, 4.5% of groupers) caught on the North Kenya Banks in the late 1950s (Morgans 1964), slightly less common (n=4 of 130 groupers) in research hook and line catches in this region by the mid 1970s (Nzioka 1977). Not commonly recorded (et al. 1994). Subsequently (to 2005), its contribution to grouper catches fluctuated between 0 and 27% by number (D. Gove, Mozambican Fisheries Research Institute, pers. comm.). Occasionally recorded in trap catches in central Mozambique from 1997 to 1998 (n=23 individuals of 1,304 groupers; Abdula et al. 2000). Rarely recorded (3 individuals of 1,278 groupers) in a survey of boat catches from non-coral reefs off the central KwaZulu-Natal coast during 1985 to 1987 (Oceanographic Research Institute 1988). Occasionally recorded (76 individuals of 12,094 groupers) from commercial boat line catches from central KZN coast (non-coral reefs) from 2002 to 2006 (Fennessy unpub. Data). Pages (Refrigepeche Est pers. comm.), operating a commercial linefishing fleet out of Tamatave (central east coast) in Madagascar, reported that this species is common, constituting about 20% of all grouper caught (total grouper catch about 30 mt yr-1). Reported in catches from Reunion (D. Miossec, pers. comm. IFREMER) but lumped with several other grouper species. Percentage contributions (assumed to be by number) to grouper catches from “essentially unexploited” deep-slope reefs were moderate to low in Melanesia (7.05%), Micronesia (2.35%) and Polynesia (0.23%) – Dalzell and Preston (1992), reported in Dalzell et al. (1996). Possibly the main grouper species caught in Seychelles; also in Djibouti/Somalia/Oman.
In terms of the inshore handline fishery, catch rates (CPUE) of the grouper guild, of which E. chlorostigma is one of the main species, have significantly declined since 1990, from over 0.6 to less than 0.3 kg/fisher/hr (Grandcourt and Cesar 2003). CPUE in the schooner handline fishery has declined significantly, from around 3.5 kg/man-day in 1986 to just over 1.0 kg/man-day since 2002. By contrast, CPUE in the whaler handline fishery has remained relatively stable since 1990 (between 0.5 and 1.2 kg/man-day), but effort estimation for these fisheries is confounded by a degree of within-trip target switching (demersal to pelagic) which may vary from year to year and is not reliably accounted for in the surveys.
Mees (1992) estimated the MSY of E. chlorostigma to be in the range of 0.013 to 0.023 mt/km², corresponding to 161 to 290 mt over the fishing ground. These estimates were based on a standing stock of 1,468 mt. Catches were maintained at just below the conservative MSY estimate until the closure of the mothership-dory fishery (Figure 1). This species is vulnerable to both pulse (mothership) and sequential fishing. High catches and CPUE prior to 1994 are thought to have been maintained through expansion of the fishery and sequential targeting. Stock assessments conducted at the level of statistical sector found localized depletions resulting from the mothership-dory fishing, and decreases in abundance at the level of sector have been detected (Mees 1996) following this period. Current length at first capture (Lc50 = 36.44 cm) is only slightly greater than 0.5L∞ (Lm50 is unknown), while F/M is 2, highlighting concern over current levels of fishing mortality (F = 0.91).
See the supplementary material for Figure 1: Total annual catch of E. chlorostigma form the Seychelles.
Catch data from commercial hook and line vessels off southern Mozambique are inconclusive – declines in recent years could be due to a spatial shift in fishing effort (Table 1).
See the supplementary material for Table 1: Catch data (port monitoring) for the Mozambican commercial line fishery.
In Oman, in three fisheries management areas, preliminary surplus production stock assessments of groupers (of which E. chlorostigma forms an important part – extent not quantified) range from over-exploited to under-exploited (Oman Fisheries department unpub. data).
|Current Population Trend:||Stable|
|Habitat and Ecology:||
Epinephelus chlorostigma is a reef-associated, non-migratory species found over a wide range of habitats like seagrass beds and outer reef slopes; in the South China Sea, it is also found on mud bottoms. Depth range from 4 to 280 m (Heemstra and Randall 1993). Maximum size 75cm TL, 7 kg (Heemstra and Randall 1993). Maximum length estimated to be 80.7 cm (MRAG 1996), reported to 80 cm TL from South Africa (Oceanographic Research Institute unpub. data).
Feeds on small fishes and crustaceans (mainly stomatopods and crabs).
Reproduction and size
Based on consistent observations of male islets in mature, active female gonads from the Seychelles, Moussac (1996) concluded that the species is protogynous, with sex change first occurring at around 34 cm TL, and the first active males appearing at 37 cm. He suggested that sex change occurs over a wide range (34 to 56 cm) and that not all females change sex. Moussac attributed a skewed sex ratio (F:M) of 2.4:1 to fishing, noted that a more balanced ratio of 1.1:1 occurs where populations are not so heavily fished. Females mature at between 23 and 29 cm TL (Heemstra and Randall 1993) while Moussac (1996) indicated a size at 1st maturity of about 31 cm. Morgans (1982) reported maturity at 25 cm SL in Kenya, while the smallest male observed was 39 cm TL (Sanders et al. 1988). The spawning season of E. chlorostigma in the Seychelles was protracted, occurring between November and April and with peaks at the beginning and end of that period (Sanders et al. 1988). These peak periods correspond to the inter-tropical monsoon months. Morgans (1964) reported ripe or nearly-ripe fish in February, March, August and September off Kenya. Nzioka (1979) reported a ripe fish in September off Kenya/northern Tanzania. While a few fishers have reported the formation of spawning aggregations (Robinson et al. 2004), mating and spatial patterns of spawning are unverified. It is considered unlikely that transient aggregations occur (or used to occur) in this species, as large aggregations of common target species are generally well known to fishers (Robinson pers. comm.).
Spawning season in Egypt (Red Sea) extended from May to end July, peaking in June. Length at 50% maturity was 28 cm TL (three years). F:M ratio 2.4:1. Mean size at sex reversal is 48 cm TL. Said to be protogynous, based on disparate length frequencies for males and females and observation of bisexual gonads. Absolute fecundity increases from age three to six, then drops at age seven. Relative fecundity 121 to 776 eggs/g body weight (Ghorab et al. 1986).
Spawning season in Oman extended from August to October and peaked in September. Length at 50% maturity is 41 cm (Oman Fisheries Dept. unpub).
In the Seychelles, it is common across the Mahe Plateau and surrounding banks, especially at depths ranging from 40 to 60 m. More abundant over rough rubble and coralline areas although it is taken in (experimental) trawls over more sandy areas (J. Robinson, Seychelles Fishing Authority, pers. comm.). In Seychelles it frequents the shelf edges of the banks and has been fished down to depths of 250 m (Intes and Bach 1989). It is less common on the atolls to the south of Seychelles and appears absent on shallow reefs (Pears 2005).
Growth and maturity
Growth parameters for E. chlorostigma from the Seychelles have been derived using a range of methods, but those considered the most reliable are given, using length based (Mees 1992, Sanders et al. 1988) or size at age approaches (Grandcourt 2002) (Table 2). Aged up to 26 years in Oman.
See the supplementary material for Table 2: Growth parameters for E. chlorostigma from the Seychelles.
Estimates of natural mortality using the growth parameters of Mees (1992) and Sanders et al. (1988) in Table 2 vary from 0.43, using Pauly (1980), to between 0.37 and 0.39 using Ralston (1987) models, which are considered more reliable for slow growing fish. Using the parameters derived by Grandcourt (2002), natural mortality estimated from Pauly is 0.37 yr-1.
Length-weight relationship y g = 0.0145.x cm FL.3.05.
|Major Threat(s):||Epinephelus chlorostigma is under intense fishing pressure regionally, yet its deep habitat may provide some natural protection.|
Epinephelus chlorostigma occurs in some protected areas throughout its range.
In KwaZulu-Natal in South Africa, most of the north coast which contains coral reefs is protected by a 145 km long MPA in which no demersal fishing is allowed, and is strictly enforced. This reserve extends to deeper waters, and so offers protection to this deep-living species.
It is intended that this MPA and the southern Mozambique coast from Ponta d’Ouro to Maputo will be incorporated into a Transboundary MPA, with areas zoned for protection, which will offer future protection to this species.
In South Africa, as part of a suite of restricted species, a maximum of five individuals of this species may be retained by recreational fishers in one day; no limits for commercial fishers. In Mozambique, a maximum of 10 individuals of demersal species may be retained by recreational fishers.
|Citation:||Choat, J.H., Craig, M.T., Fennessy, S., Ferreira, B., Bertoncini, A.A., Robinson, J. & Rocha, L. 2008. Epinephelus chlorostigma. The IUCN Red List of Threatened Species 2008: e.T132823A3461108. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T132823A3461108.en . Downloaded on 07 October 2015.|