The Sailfin Snapper

Symphorichthys spilurus

spilurus_pl_colin

Photo: P.L. Colin

Description and Distribution
Sailfin snapper, otherwise known as blue-lined sea bream, has a distribution in the Indo-Pacific. It is often found in the western Pacific, from the Ryukyu Islands to New Caledonia and the Great Barrier Reef, including Admiralty Islands, New Guinea, Palau, Philippines, Sulawesi (Celebes), and Tonga. The species is also known from the eastern Indian Ocean from Rowley Shoals and off Broome, Western Australia (1,5).

S. spilurus is not commonly found and little is known of its biology. It is a commercial fish mostly targeted for the aquarium trade because it is particularly attractive as a juvenile. It has distinct lateral lines running parallel from the eyes to the tail (black stripes as juvenile and blue lines against yellowish body when matured). It also possesses long pectoral fin, reaching level of anus and soft rays of dorsal and anal fins produced into filaments. The maximum reported length of the species was 60 cm (TL), while generally they grow to 50 cm (TL) (1,2,5)


Preferred Habitat
S. spilurus is reef-associated, found on coral reefs or over sand bottoms in the vicinity of coral reefs. It is usually seen singly and normally occurs at depths of 5 to 60 m (1,5).


Life History
S. spilurusis a moderate-sized carnivorous species. It feeds mainly on sand-dwelling molluscs and crustaceans, also on fishes. It undergoes considerable ontogenetic changes in body shape and colouration between the juvenile and adult stage (1,2,5,7).


Spawning Aggregations

S. spilurus is found forming spawning aggregations along seaward reefs. Reported transient spawning aggregations were observed in spring (March, April, May) in Papua New Guinea during third quarter lunar phase and at least one aggregation is known from Palau (3,5,6,8, P. Colin, pers. comm..)

stampPhoto: Yvonne Sadovy

Fisheries
S. spilurus has a very high commercial value. It is especially favoured in the aquarium trade. This species is fished mainly with hand-lines and spearguns. It is occasionally seen in markets and is also being traded as aquarium fish. In Papua New Guinea, where spear fishermen have exploited an aggregation of this species for several decades, several spear fishers working together can remove 20 fish in an afternoon (3,5,6).


Mariculture

No information. There is no reported research or commercial culture of the species.


Conservation & Management

There is no known conservation or management activity targeted towards this species and it has not been evaluated under for the IUCN red list. Limited information indicates that aggregations are little fished and there is no indication of changes in catch rates. The species has moderate vulnerability and medium resilience towards fishery. More information is needed to assess the species (5,6).

 

References

1. Allen G.R. (1985) Snappers of the World. An Annotated and Illustrated Catalogue of Lutjanid Species known to Date. FAO Species Catalogue. Vol. 6. FAO. Rome. Pp. 208, Pl. I-XXVII.

2. Anderson W.D.Jr. & Allen G.R. (2001) Lutjanidae. Jobfishes. p. 2840-2918. In: K.E. Carpenter and V. Niem (eds.) FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Vol. 5. Bony fishes part 3 (Menidae to Pomacentridae). FAO, Rome

3. Domeier M.L. & Colin P.L. (1997) Tropical reef fish spawning aggregations: defined and reviewed. Bulletin of Marine Science, 60(3):698-726.

4. FAO-FIES (2008) Aquatic Sciences and Fisheries Information System (ASFIS) species list.

5. Fishbase (2009) http://www.fishbase.org/summary/speciessummary.php?id=214

6. Hamilton R. (2003) A report on the current status of exploited reef fish aggregations in the Solomon Islands and Papua New Guinea - Choiseul, Ysabel, Bouganville and Manus Provinces, Western Pacific Fisher Survey Series: Society for the Conservation of Reef Fish Aggregations. Volume 1.

7. Leis J.M & Bray D.J (1995) Larval development in the Lutjanid subfamily paradicichtyinae (pisces): the genera symphorus and symphorichthys. Bulletin of Marine Science, 56(2): 418-433.

8. Martinez-Andrade F. (2003). A comparison of life histories and ecological aspects among snappers (Pisces: lutjanidae) http://etd.lsu.edu/docs/available/etd-1113103-230518/unrestricted/Martinez-Andrade_dis.pdf

Brown Marbled Grouper

Epinephelus fuscoguttatus

e_fuscoguttatus2 Photo: Seapics

Description and Distribution
Epinephelus fuscoguttatus (brown marbled grouper) is a large-bodied grouper in the family Serranidae, reaching approximately 1 m in total length (TL). The species is widespread throughout the Indo-Pacific, including the Red Sea, and is often confused with the similar-looking, co-occurring but smaller, E. polyphekadion (camouflage grouper) (6).


Preferred Habitat
E. fuscoguttatus is reef-associated, occurs in lagoon pinnacles, channels, and outer reef slopes, in coral-rich areas with clear waters at depths ranging from 1 to 60 m. Juveniles occur in seagrass beds (3,6,12).

 

e_fuscoguttatus_rangeSource: SCRFA
The above diagram shows the range of brown marbled grouper (highlighted in green)
and reported spawning aggregation sites (highlighted in red)

 

Life History
Brown marbled grouper is naturally uncommon, and is relatively long-lived (lifespan can exceed 40 years) and attains about 100 cm (TL). Estimates of size and age at effective maturity, where 50 percent of females are sexually active during the spawning season, are 57 cm (TL) and 9-10 years of age (11,12).

The sexual pattern appears to be monandric protogyny in which juveniles mature and then function first as adult females before changing sex, although confirmation of sex change is still required. The postulated life history strategy is one in which energy is primarily invested in body growth for 9-10 years; afterwards growth slows and energy is invested in reproduction. Large females make important reproductive contributions during their 30+ year reproductive lifespan. Estimates of 50% effective maturity calculated from the percentage of females that were sexually active during the spawning season were approximately 56 cm (TL) and 9 years. The high fecundity female breeders do not occur until almost 60 cm TL. There are females up to at least 85 cm (TL) with the smallest mature female recorded as 42 cm (TL). No males smaller than about 70 cm (TL) are known (8,11,12).

Brown marbled grouper is only known to spawn in aggregations. Large, old females may also have additional roles in the social system. Younger and inexperienced individuals may learn the way to traditional spawning sites by migrating with experienced fish. It will be important to maintain the natural size and age structures, and enough individuals of both sexes to ensure spawning aggregations continue to function (2,19,21,25).

Spawning aggregations
While reported spawning duration each year for E. fuscoguttatus is relatively short for a coral reef fish (e.g. three months), timing of spawning each year and its and lunar periodicity variy widely across the Indo-Pacific. It has been reported to aggregate in relatively large numbers to spawn, with over 350 individuals being counted at spawning aggregation sites in Palau, and a total aggregation abundance of between two and five thousand individuals being estimated in the Seychelles. Spawning aggregations are known from Australia, British Indian Ocean Territory, Federated States of Micronesia, Fiji, Indonesia, Malaysia, New Caledonia, Palau, Seychelles and Solomon Islands. Aggregation sites of E. fuscoguttatus are often found close to those of E. polyphekadion and other sympatric groupers especially as Plectropomus areolatus (squaretail coral grouper), P. laevis (blacksaddled coralgrouper) or P. punctatus (marbled coral grouper) (3,8,11,12,14,15,16).

Several studies provide important insights into reproductive activity of brown marbled coral grouper. On the Great Barrier Reef, Australia, one detailed study identified the spawning period for E. fuscoguttatus to be November to January. The prolonged period of male inactivity each year corroborates the finding of a relatively narrow spawning period for the species in other areas. In the Seychelles, transient (short term and away from the species home range) aggregations related to spawning activity may form for over just 2 weeks for each of 2 to 3 months per year (November to January). Female E. fuscoguttatus may spawn more than once during an particular aggregation period. Three or four significant spawning aggregations formed annually in Palau, with the peak between 1 and 7 days before the new moon and duration of around 5 days (May to September). Results also indicated that spawning may occur at other times of the month based on the finding of near-ripe females. Recent work on E. fuscoguttatus in Komodo National Park, Indonesia, reported that aggregations were most distinct during full moon periods between September and February. In Pohnpei, 1,085 individuals were recorded during monitoring over three days of March 2001 around the full moon period (8,11,12,14,15,16,17).

e_fuscoguttatus_randy_thamanPhoto: Randy Thaman

 

Fisheries
E. fuscoguttatus is heavily sought for the live reef food fish trade. It can be cultured by hatcheries but is still extensively taken from the wild, including from spawning aggregations. It is ciguatoxic in some areas which probably means reduced pressure, as in New Caledonia. The species is caught by hook and line, traps, spears, gillnets, traps, trawls, hook and line, speargun (3,6).

Brown marbled grouper is one of the most important species in Palau fishery. At least five grouper spawning aggregations have disappeared since the 1970s in Palau, maybe due to overfishing: one mostly of E. polyphekadion and E. fuscoguttatus lost in the 1990s, and one mostly of Plectropomus areolatus and E. fuscoguttatus was virtually eliminated in the late 1980s by a live grouper export fishing enterprise In Maldives, the species is heavily targeted and overfished. Declines due to fishing have also been indicated from interviews of fishers in Fiji (Y. Sadovy, pers. comm.) (8,24).

Imports of E. fuscoguttatus into Hong Kong are around 150 t, and major source countries for this species were Indonesia, Maldives, and the Philippines. A survey of the imports of live fish in Hong Kong revealed that E. fuscoguttatus made up 7% (approx 1,700 t) of the total annual import volume (by weight) of fish imported in 1997. The fish comes from both wild-caught individuals as well as those produced by hatcheries. Common size ranges for consumption in the Hong Kong seafood trade are 33 - 48 and 70 - 118 cm (TL). Juveniles are commonly sold in Hong Kong reef fish food market because of the smaller preferred size range for restaurants and markets (9,10,20).


Mariculture
E. fuscoguttatus can be produced in hatcheries (i.e. full cycle culture) in many countries in Asia, including Indonesia, India, Malaysia, Philippines, Taiwan, Thailand, also Australia and the Middle East. Hatcheries in northern Bali (Indonesia) were estimated to produce 6,000,000 fingerlings per year in 2006 and 2007. In the Philippines and elsewhere, juveniles were sometimes caught inshore and then grown-out in floating cages to attain market size (3,7).

Much of the brown marbled grouper being provided to the live fish markets in Hong Kong and mainland China now appears to be from mariculture (Mike Rimmer, pers. comm. 2009).

Threats
E. fuscoguttatus is listed as ‘Near Threatened' on the IUCN Red List (assessed 2004). The species is inherently vulnerable to fishing due to its late maturation, aggregation-spawning (when aggregations are targeted) characteristics and high economic value in the live reef food fish trade. Spawning aggregations are sometimes targeted resulting in large catch volume consisting of large individuals. Such fishing practices have been implicated in the decline or disappearance of spawning aggregations of this and other related species (3,12,22).

The degree of protection afforded E. fuscoguttatus spawning aggregations varies widely, and typically is inadequate for preventing declines. For example, out of 34 records for E. fuscoguttatus in the global spawning aggregation database, 11 spawning aggregations (32%) are decreasing. Within multi-species reef fisheries, late maturing, aggregation-spawning groupers will be more vulnerable species to overfishing during both aggregation and non-aggregation periods (www.scrfa.org).


Conservation & Management
E. fuscoguttatus is relatively uncommon and its spawning aggregation sites appear to be scarce, making protection of these sites from overfishing a high priority. A better understanding of the area from which a particular aggregation site draws individuals would help in determining the scales of potential fishing effects and for designing locally appropriate management strategies. Similarly, it is important to determine biological characteristics, such as maturity and spawning periods, locally, to ensure management arrangements are appropriate to local conditions (1,4,16).

Beginning in the 1980s, the Pohnpei State Government began implementing measures to reduce fishing effort on groupers, including a partial sales ban during the spawning season. In 1995, the Kehpara Marine Sanctuary was established, but the northwest boundary fell short of covering brown marbled grouper aggregations, so fishing continued. No foreign fishing vessels are allowed and entry restrictions for divers at one site. However, one shortcoming of the current regulation is that aggregation extend at least one month beyond the protected period (5,15).

Similarly in Palau, the Marine Protection Act of 1994 prohibits sale or purchase of E. fuscoguttatus from April 1 through July 31 each year, intended to protect spawning aggregations. Local traditional ‘buls' reinforce this protection. In 1995 the Act was amended to prohibit any capture of these groupers even for subsistence purposes duringthe closed period. A four-month taboo (bul) was enforced in certain states, but was not completely effective in preventing fishing on the spawning aggregation, which was said by fishermen to be much smaller than they had been ten years ago; poaching is common. Exports are monitored, no foreign fishing vessels are allowed Aggregations extend at least one month beyond protection (8).

In Papua New Guinea, dynamiting and night-time spearfishing at a known spawning aggregation site is prohibited under customary law. In Komodo Marine Park, Indonesia, spawning aggregation protected zones with seasonal closure recommended for traditional use zones (13,14).

In Australia, a minimum capture size limit of 35 cm (TL) and a bag limit on this species apply across all sectors of the coral reef fin fish fishery including for commercial and recreational fishers and charter boat operators. Minimum size limits are set at a point which allows at least half of the fish in a population to reach reproductive maturity and spawn before they are available for harvest. In Great Barrier Reef (GBR), the seasonal closures for the three 9-day periods around the new moons in October to December offer limited protection to E. fuscoguttatus because aggregating behaviour is predicted to occur throughout much of the lunar cycle between November and January. Consideration should be given to a blanket catch ban for E. fuscoguttatus during reproductive months since mature-sized fish captured at any time within the spawning period are potentially reproductively active. Some of thespawning aggregations may be protected in no-take zones within the GBR network of marine protected areas (11,12,18).

 

References

1. Aumeeruddy R. & Robinson J. (2006) Closure of the live reef food fish fishery in Seychelles. SPC Information Bulletin. Live Reef Fish 16:3-9
2. Coleman F.C., Koenig C.C. & Collins L.A. (1996). Reproductive styles of shallowwater groupers (Pisces: Serranidae) in the eastern Gulf of Mexico and the consequences of fishing on spawning aggregations. Environmental Biology of Fishes47, 129-141.
3. Cornish A. (2004) Epinephelus fuscoguttatus. In: IUCN 2009. 2009 IUCN Red List of Threatened Species. <www.iucnredlist.org>
4. Graham N., Wilson S., Jennings S., Polunin N., Bijoux J. & Robinson J. (2006) Dynamic fragility of oceanic coral reef ecosystems. Proceedings of the National Academy of Sciences 103:8425-8429
5. Hamilton R.J., Matawai M., Potuku T., Kama W., Lahui P., Warku J. & Smith A. (2005) Applying local knowledge and science to the management of grouper aggregation sites in Melanesia. SPC Information Bulletin. Live Reef Fish 14:7-19
6. Heemstra P.C. & Randall J.E. (1993) FAO species catalogue. Vol 16. Groupers of the world (Family Serranidae, Subfamily Epinephelinae). p 382
7. James C.M., Al-thobaiti S.A., Rasem B.M. & Carlos M.H. (1998) Comparative growth of brown-marbled grouper Epinephelus fuscoguttatus and camouflage grouper E. polyphekadion under hatchery and growout culture conditions. Asian Fisheries Society 11:133-147
8. Johannes R.E., Squire L.C., Graham T., Sadovy Y. & Renguul H. (1999) Spawning aggregations of groupers (Serranidae) in Palau. Report No. 1, The Nature Conservancy
9. Lau, P.F. & Parry-Jones, R. (1999). The Hong Kong Trade in Live Reef Fish for Food. TRAFFIC East Asia and World Wide Fund for Nature Hong Kong, Hong Kong.
10. Lee, C. & Sadovy, Y. (1998) A taste for live fish: Hong Kong's live reef fish market. Naga, ICLARM 21(2): 38-42.
11. Pears R.J., Choat J.H., Mapstone B.D. & Begg G.A. (2006) Demography of a large grouper, Epinephelus fuscoguttatus, from the Great Barrier Reef: implications for fishery management. Marine Ecology Progress Series 307:259-272
12. Pears R.J., Choat J.H., Mapstone B.D. & Begg G.A. (2007) Reproductive biology of a large, aggregation-spawning serranid, Epinephelus fuscoguttatus: management implications. Journal of Fish Biology 71:795-817
13. Pet J. & Yeager C. (eds) (2000) 25 Year master plan for Komodo National Park, book 1, management plan, Ministry of Forestry, Department of Nature Protection and Conservation, Jakata, Indonesia
14. Pet J.S., Mous P.J., Muljadi A.H., Sadovy Y.J.& Squire L. (2005) Aggregations of Plectropomus areolatus and Epinephelus fuscoguttatus (groupers, Serranidae) in the Komodo National Park, Indonesia: Monitoring and Implications for Management. Environmental Biology of Fishes V74:209-218
15. Rhodes K.L. & Sadovy Y. (2002) Temporal and spatial trends in spawning aggregations of camouflage grouper in Pohnpei, Micronesia. Environmental biology of fishes 63:27-39
16. Robinson J., Cedras M. & Jorgensen T.L. (2004a) Spawning aggregations of Epinephelus fuscoguttatus and E. polyphekadion at Farquhar Atoll, Seychelles: preliminary field studies, Technical Report SFA/R&D/060, Seychelles Fishing Authority (SFA), Seychelles
17. Robinson J., Isidore M., Marguerite M.A., Öhman M.C. & Payet R.J. (2004b) Spatial and temporal distribution of reef fish spawning aggregations in the Seychelles - An interview-based survey of artisanal fishers. Journal of Marine Science 3:63-69
18. Russell M. & Pears R. (eds) (2007) Workshop summary: management and science of fish spawning aggregations in the Great Barrier Reef Marine Park, 12-13 July 2007, Great Barrier Reef Marine Park Authority, Townsville, Museum of Tropical Queensland, Townsville, Australia
19. Sadovy Y. (1996). Reproduction of reef fishery species. In Reef Fisheries (Polunin, N. V. C. & Roberts, C. M., eds), pp. 15-59. London: Chapman & Hall.
20. Sadovy Y.J., Donaldson T.J., Graham T.R., McGilvray F., Muldoon G.J., Phillips M.J., Rimmer M.A., Smith A. & Yeeting B. (eds) (2003) While Stocks Last: The Live Reef Food Fish Trade, Asian Development Bank, Manila, Philippines
21. Sadovy Y. & Domeier M. L. (2005). Are aggregation-fisheries sustainable? Reef fish fisheries as a case study. Coral Reefs 24, 254-262.
22. Sadovy Y. (2005) Troubled times for trysting trio: three aggregating groupers in the live reef food fish trade. SPC Live Reef Fish Bulletin 13
23. SFA (2006) Annual Report 2006, Seychelles Fishing Authority, Mahe, Seychelles
24. Sluka R.D. (2002) Grouper and Napoleon wrasse ecology in Laamu Atoll, Republic of Maldives: part 3. Fishing effects and management of the live fish-food trade. Atoll Research Bulletin 2001: 481-493.
25. Trippel E. A., Kjesbu, O. S. & Solemdal, P. (1997). Effects of age and size structure on reproductive output in marine fishes. In Early Life History and Recruitment in Fish Populations (Chambers, C. R. & Trippel, E. A., eds), pp. 31-62. New York: Chapman & Hall

Squaretail Coralgrouper

 plectro_areolatusPhoto: John E. Randall

 

Plectropomus areolatus 

Description and Distribution

Head, body and median fins greenish grey to brown or brownish red, with numerous round to oval dark-edged blue spots (the largest about equal to a pupil); most spots are within a spot diameter of adjacent spots. The pelvic fins have dark brown to blackish membranes. The rear margin of the caudal fin has a white edge, often with a blackish submarginal band (1).

The squaretail coralgrouper is found in the Indo-Pacific from the Red Sea to the Phoenix Islands and Samoa, north to the Ryukyu Islands and south to Australia (2).

Preferred Habitat

This species inhabits lagoon and seaward reefs, especially areas with rich coral growth, and is most frequently encountered in channels along the reef front. It is found in a depth range of 1-20m.

Biology

Juveniles - No information.

Adults - The squaretail coralgrouper feeds exclusively on fishes. Often reaches 60 cm (3). The maximum length is 73 cm (4). Maturity size range is 31-35 cm TL (7).

Spawning aggregations

Spawning aggregations are known from the Solomon Islands, Palau; Pohnpei, Micronesia, Maldives, Australia, Kiribati, Fiji, Marshall Is., Indonesia, Tuvalu, and Samoa, amongst other locations.

One study showed that large numbers gathered in the seaward end of Ulong Channel, Palau, a few days before the new moon in May. The males displayed light bodies with about five irregular dark saddles and dark dorsal and anal fins (5).

Twice-monthly monitoring at sites in Komodo National Park, Eastern Indonesia, over five years, found aggregations typically formed during each full moon between September and February. Additionally, the squaretail coralgrouper occasionally aggregated during new moons between April and July (6).

Mariculture

No information; the species is not cultured.

Commercial Use

In Pacific countries it is one the most abundant and main target grouper species for the live reef fish food trade. It is sold in the Hong Kong live reef fish food market. Imports of the squaretail coralgrouper to Hong Kong were 2,319 tonnes in 1997. Common size at consumption is 38.24 - 50.21 cm TL (7).

In parts of Kiribati, local knowledge collected indicates spawning season from September to February with spawning peak occurring in early December. Fishing targeting spawning aggregations was traditionally practiced but became very intensive in the 1980's when an Outer island Fisheries Project was started which buys fish from the outer islands to sell in Tarawa, the capital. At the peak season of fishing during this time, an estimated catch of 2 tonnes of fish (about 1200 individuals) per day was normal (similar volumes are reported elsewhere and can represent a large proportion of fish aggregating at any one time). A UVC survey was conducted then which showed mean density of 0.13 individuals per 100sq.m and with mean TL of 40cms. In 2004 another survey was done at the same island, giving a mean density of 0.04 individuals per 100sq.m and mean TL of 33 cms (9).

Threats

Reports show declining stocks in Palau almost certain due to overfishing of aggregations. Before actual spawning around full moon, the species aggregates along outer reef channels and is responsive to baited hooks, making them very vulnerable to fishing; upward movements of some to take baited hooks has been mistaken for courtship or spawning behaviour. At least four grouper spawning aggregations have disappeared since the 1970s, and others are much reduced.

Conservation and Management

In Palau, the Marine Protection Act of 1994 and local traditional law prohibit sale or purchase of the squaretail coralgrouper from April 1 through July 31 each year, intended to protect spawning aggregation; however aggregations may extend into August, leaving fish unprotected at this time. In 1995 the Act was amended to prohibit any capture of these groupers even for subsistence purpose in the closed period (8).

In Australia, minimum size limits of 38 cm and a total combined daily bag limit of 7 coral trout apply to this species. Minimum size limits proposed for coral reef fin fishes are set at a point which allows at least half of the fish in a population to reach reproductive maturity and spawn before they are available for harvest; however, there is no indication that this is an appropriate size and longer lived species likely need much longer to replace themselves, on average, according to life history theory.

Conservation Status

In the IUCN (World Conservation Union) Red List, the species is included as ‘Vulnerable' because of the high demand and heavy pressure, thought to be increasing, on its spawning aggregations. Greatest catches of this species are taken at aggregations, being generally low at non-spawning times of the year.

Information Needed

Juveniles

References

(1) P.C. Heemstra and J.E. Randall. 1993. FAO species catalogue Vol. 16. Groupers of the world (Family Serranidae, Subfamily Epinephelinae). An annotated and illustrated catalogue of the grouper, rockcod, hind, coral grouper and lyretail species known to date ( Food and Agriculture Organization of the United Nations, Rome, 1993), 289pp.

(2) Fishbase website, www.fishbase.org.

(3) Heemstra and Randall, Loc. Cit. 1993 p. 289.

(4) Fishbase website, www.fishbase.org.

(5) Myers. 1989. Micronesian Reef Fishes. Coral Graphics.

(6) J,S. Pet, Peter J. Mous, A.H. Muljadi, Y.J. Sadovy and L. Squire. 2005. Aggregations of Plectropomus areolatus and Epinephelus fuscoguttatus (groupers, Serranidae) in the Komodo National Park, Indonesia: Monitoring and Implications for Management. In: Environmental Biology of Fishes 74(2) / October, 2005 .

(7) P.P.F. Lau and R. Parry-Jones, "The Hong Kong trade in live reef fish for food'' TRAFFIC East Asia and World Wide Fund for Nature, Hong Kong (1999)

(8) R.E. Johannes, L. Squire, T. Graham, Y. Sadovy and H. Renguul, ‘' Spawning aggregations of groupers (Serranidae) in Palau,'' The Nat.Conserv. Mar. Res. Ser. Publ. No. 1 (1999): 144 pp.

(9) Being Yeeting, 1999, unpublished report; Secretariat of the Pacific Community ProcFish data, 2005

Coral Trout / Leopard Coral Grouper

p_leopardus Photo: John E. Randall

 

Plectropomus leopardus

Description and Distribution

The coral trout, otherwise known as the leopard coral grouper, is distributed across the western Pacific from southern Japan to southern Queensland, west to Lombok, Indonesia and Western Australia, and east to Caroline Islands and Fiji; occurring at depths of 3 to 100m. It is listed as near threatened in the IUCN red list (Assessed in 2004). Plectropomus leopardus is a medium-sized diurnally active grouper easily observed underwater, therefore vulnerable to spear fishing but also amenable to accurate visual census surveys. They can live up to 14-19 years with maximum length reaching 63.0 FL (female) and 74.6 FL (male) (4,5,8,11,12,24,30).

Preferred Habitat

The larvae are pelagic; juveniles live in demersal shallow water in reef habitats, especially around coral rubble, whereas adults inhabit coral reefs (2,11,25).

p_leopardus_range Source: SCRFA
The above diagram shows the range of the coral trout (highlighted in green)
and reported spawning aggregation sites (highlighted in red)

 

Life History

P. leopardus grows rapidly in the first 2-3 years of life, and matures relatively early. As juveniles their diet consists largely of benthic crustaceans, but this shifts just prior to maturity to a piscivorous diet. Recruitment of juveniles appears to be largely driven by current patterns and geomorphology. P. leopardus is a protogynous hermaphrodite, maturing as female first and then changing to male at around 7 years. The operational sex ratio (F:M) largely varies with location and exposure to fishing - ranging from 0.9 to 5.5 (1,2,3,8,12,25, 28).

The mating patterns of P. leopardus illustrate a relatively complex and flexible reproductive strategy compared with other serranids of similar size. The high spawning frequency and high annual fecundities, at least double those of other serranids, may be the reason why P. leopardus is a relatively abundant serranid and is perhaps more resistant to fishing pressure (5,7,9,16,21,23).

Spawning Aggregations

On the northern GBR, P. leopardus forms well defined, spatially and temporally predictable spawning aggregations at the same sites over years. Aggregations form for a five day period around the new moon over three months during Austral spring to early summer. Pair spawning in aggregations is confined to a 30 minute period at sunset. However, only around 20% of individuals appear to participate in aggregation spawning. Further, around 50% of all spawning occurs outside aggregations including those happened during the first quarter lunar phase (3,9,10,20,27).

p_leopardus2 Photo: Seapics

Fisheries

The generic group coral trout, which comprise three main species (leopardus, laevis and maculatus), and four lesser species, are the major commercial finfish taken in Australia, predominantly on the Great Barrier Reef (GBR). Commercial log books do not distinguish the Plectropomus species, but independent research shows that leopardus comprises 80% of the Plectropomus commercial catch. It is also the most abundant of the Plectropomus species on the GBR (10).

Commercial log book data show significant increases in catch and effort of Plectropomus spp. on the GBR. In 2000 the commercial harvest was worth AUS$ 15.5 million. P. leopardus is also taken on the GBR by private recreational fishers and by a commercial charter fishery for recreational fishers. P. leopardus is also taken commercially and recreationally from the Houtman Albrolhos islands in Western Australia (WA). The WA fishery is managed through minimum size limits, recreational bag limits and area closures and is not considered overexploited. Artisanal fisheries for P. leopardus exist in the Pacific Islands where they occur, namely Fiji, Papua New Guinea, New Caledonia and elsewhere in Southeast Asia (15,25).

In the mid 1990s the trade in live P. leopardus, primarily to Hong Kong, grew in Australia and the Philippines and the portion of live fish in the commercial catch grew to around 25%. By 1998 live coral trout fetched up to eight times the price of whole or filleted coral trout.  The export of live P. leopardus has been a significant commercial fishery in the Asia-Pacific region, with fish taken primarily from Indonesia and Philippines. Imports into Hong Kong increased by 58% from 1999 to 2002, coming largely from Australia and Philippines as other countries' exports declined. Although the majority of P. leopardus in Hong Kong live fish markets are above size at first reproduction, capture of juveniles and grow out is practised, particularly in the Philippines (11).

Commercial fishers in Australia use simple hook and line, generally with one hook, with frozen pilchard as bait, fishing from small tender boats to a mother vessel. Recreational fishers use handlines, rods and spearguns.  Mother vessels have large freezer capacity and may stay out for 3-4 weeks. Artisanal fisheries in Fiji and New Caledonia take P. leopardus by hook and line and spear gun, and incidentally by trap and net. Some are kept live for the live fish trade. In the Philippines, fish are caught by hook&line and by cyanide solution (24)

P. leopardus is a high-valued and much sought-after grouper species. Some 2000 tonnes of this species are imported to Hong Kong, the major trade centre, from countries like Australia, Indonesia, Malaysia, Vietnam, and the Philippines. The retail price of the species in Hong Kong and mainland China ranges from 50-70USD/kg in 2002 (19).

(2,20,27).

Mariculture

P. leopardusis a popular candidate for mariculture in Asia-Pacific region - the collection of wild broodfish, application of hatchery and grow-out husbandry (17, 29).

Coral Trout in Fish Tank
p_leopardus3 
Photo: Yvonne Sadovy de Mitcheson


Threats

There is no strong evidence of targeted fishing of spawning aggregations of P. leopardus on the GBR. However, the potential for increased catchability due to P. leopardus moving from habitats inaccessible to fishers to regularly fished areas while migrating to aggregations has been demonstrated through simulation. The collapse, recovery and further collapse of one spawning aggregation in the Cairns region of the GBR was attributed to commercial fishers targeting this site. It is likely that easily located aggregation sites are vulnerable to targeted fishing but the relatively small aggregations and several aggregations per reef of P. leopardus makes it less vulnerable than other groupers. No intentional targeting of spawning aggregations is reported from the Torres Straits (13,14,30,32)

Aggregation fishing is known from the Asia- Pacific region in connection with the live fish trade to Asia. The extent to which this targets P. leopardus aggregations is not known. However, aggregation fishing for live groupers in Indonesia has been so great that severe declines in catches were experienced and these are likely to include P. leopardus. Most studies and conservation action in the Asia-Pacific region have focussed on Plectropomus areolatus, and there is little known or discussed of P. leopardus, except in Australia (9,27).

In the Philippines, large number of sub-adult sized fish are put into net cage and grown-on to market-size. This practice, if not managed carefully could lead to recruitment overfishing and growth overfishing (19).

Conservation & Management

Conservation and management action is largely limited to Australia where the commercial Queensland fishery is limited entry, licensed, with gear restrictions and a minimum size limit of 36cm FL. The size limit prevents fishing of the first three cohorts, representing both the fastest growth period as well as when females start reproducing. Recreational fishers are limited to 10 coral trout per person. Charter fishing operators are regulated by permits & bag limits.

The Queensland reef fishery operates within the GBR Marine Park with area closures where fishing is prohibited. Studies on the impacts of these closures on P. leopardus reveal complex results, but generally females are larger, older and more abundant on closed reefs suggesting reef closures are an effective strategy against fecundity limitation. Despite extensive fisheries and protected area controls, significant declines in P. leopardus abundance in the central and southern sections of the GBR are reported. This observation together with the decline in catch rate since the early 1990s, has led to reviews and revision of legislation. In 2002 the Queensland Fisheries Service introduced three 10 day closures (around the new moon) (reduced to 2 days in 2009) to protect spawning aggregations of key target species but designed primarily to protect P. leopardus aggregations and migrations.   Meanwhile the management authority completed a massive re-zoning of the park in 2004, resulting in 33% of the Park being closed to fishing.

The Houtman Albrolhos Islands in WA have been  declared a Fish Habitat Area (FHA) by the Department of Fisheries. Seventeen percent of the FHA was closed to fishing in 1994. After eight years of closure P. leopardus densities increased 3-7 fold which was attributed to reduced fishing mortality and their relatively small home ranges. No information is reported on their spawning aggregations in WA.

The status of P. leopardus populations in Pacific Island countries and the role aggregation fishing plays in the export fishery for live fish is largely unknown. Volumes of catches of high value groupers in the live trade from Indonesia, Malaysia, Cambodia and Vietnam have plummeted while imports to Hong Kong continue to rise.

Because P. leopardus aggregations are relatively small, there are several per reef and aggregation spawning contributes relatively little to the total reproductive output, management and conservation of P. leopardus in Australia is probably best focussed on the species in general. However, in the Philippines, Indonesia and Fiji where substantial trade in live coral trout occurs, complete protection of spawning aggregations through seasonal closures is likely to be a more important measure. In the Philippines a management plan is being developed for Palawan (Sadovy pers comm).
(1,3,6,7,14,30,33)


Information Needed

Biological and ecological studies of P. leopardus from across its range, particularly from the Indian Ocean, Philippines, Fiji, Japan and Indonesia; data on species-specific abundance, catch and effort in the artisanal fisheries of the Pacific Islands to properly assess the population status of this species; knowledge of reproductive parameters and spawning behaviour of populations; monitoring of aggregations and of the impacts of spawning closures as part of fisheries management.

 

References

1. Adams, S., Mapstone, B.D., Russ, G.R. and Davies, C. (2000) Geographic variation in the sex ratio, sex specific size, and age structure of Plectropomus leopardus (Serranidae) between reefs open and closed to fishing on the Great Barrier Reef. Can. J. Fish. Aquat. Sci. 57: 1448-1458.
2. Ayling, A.M, and Ayling, A.L. (1992) Abundance, distribution and length frequencies of a group of large piscivorous fishes, Plectropomus spp. (Pisces: Serranidae) on the Great Barrier Reef. Unpublished Report to GBRMPA.
3. Ayling, AM, Samoilys, MA and Ryan, D (2000) Trends in common coral trout populations on the Great Barrier Reef. A Report to Queensland Fisheries Management Authority. Inf. Ser. Dep. Prim. Ind. (Queensl.); QDPI, Brisbane, Qld., Australia, 37pp.
4. Cornish, A. & Kiwi, L.K. 2004. Plectropomus leopardus. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. <www.iucnredlist.org>
5. Doherty, PJ, Fowler, AJ, Samoilys, MA and Harris, DA (1994) Monitoring the replenishment of coral trout (Pisces:Serranidae) populations. Bull. Mar. Sci. 54(1): 343-355.
6. Fernandes, L. et al. (2005). Establishing representative no-take areas in the Great Barrier Reef: large-scale implementation of theory on marine protected areas. Conservation Biology: 1733-1744.
7. Ferreira, B.P. (1995). Reproduction of the common coral trout Plectropomus leopardus from the central and northern Great Barrier Reef. Bull. Mar. Sci. 56(2):653-669
8. Ferreira, B.P., Russ, G.R. (1994). Age validation and estimation of growth rate of the coral trout, Plectropomus leopardus, (Lacepede 1802) from Lizard Island, northern Great Barrier Reef. Fish. Bull. US 92:46-57
9. Fulton, E., Kault, D., Mapstone, B., and Sheaves, M. (1999). Spawning season influences on commercial catch rates: computer simulations and Plectropomus leopardus, a case in point. Can. J. Fish. Aquat. Sci. 56: 1096-1108.
10. GBRMPA (in press). Management and science of fish spawning aggregations in the Great Barrier Reef Marine Park. Workshop Summary report.
11. Heemstra, P.C., Randall, J.E. (1993). FAO Species Catalogue: Groupers of the World. Vol. 16. Food and Agriculture Organisation of the United Nations, Rome. 382pp.
12. Loubens, G. (1980) Biologie de quelques especes de poissons du lagon Neo-Caledonien. III. Croissance. Cahiers de l'Indo-pacifique 2 : 101-153.
13. Mapstone, B.D. et al. (2004) The effects of line fishing on the Great Barrier Reef and evaluations of alternative potential management strategies. CRC Reef Research Centre Technical Report No. 54, CRC Reef Research Centre Townsville, 205pp.
14. Nardi K., Jones, G.P., Moran, M.J. and Y.W. Chen (2004) Contrasting effects of marine protected areas on the abundance of two exploited reef fishes at the sub-tropical Houtman Abrolhos Ilsnads, Western Australia. Env. Cons. 31(2): 160-168.
15. Russ, G.R., Lou, D.C., Higgs, J. and B.P. Ferreira (1998) Mortality rate of a cohort of the coral trout, Plectropomus leopardus, in zones of the Great barrier Reef Marine Park closed to fishing. Mar. Freshwater Res. 49:507-511.
16. Sadovy, Y.J. (1996). Reproduction of reef fishery species. In: Management of Reef Fisheries, pp. 15-59, Polunin, N.V.C., Roberts, C.M., eds. Chapman & Hall, London
17. Sadovy, Y.J. & Pet J. (1998) Wild collection of juveniles for grouper mariculture: just another capture fishery? SPC Live Reef Fish Information Bulletin 4: 36-39.
18. Sadovy, Y.J. and Vincent A.C.J. (2000) Ecological issues and the trade in live reef fishes. In: Sale, P.P. (ed.), Coral Reef Fishes Dynamics and Diversity in a Complex Ecosystem. Academic Press, San Diego, pp. 391-420.
19. Sadovy, Y.J. et al. (2003) While stock last - the live reef food fish trade. Asian development bank. 147pp.
20. Samoilys, MA (1997) Periodicity of spawning aggregations of coral trout, Plectropomus leopardus (Pisces: Serranidae) on the northern Great Barrier Reef. Mar. Ecol. Prog. Ser. 160:149-159.
21. Samoilys, M.A. (2000). Reproductive dynamics of an exploited serranid on the Great Barrier Reef. PhD thesis, James Cook University. 106 pp + Appendix.
22. Samoilys, M. et al. (1995) Application of Underwater Visual Census to Assessing Coral Reef Fish Stocks in the Tropical Pacific. Report prepared for the Australian Centre for International Agricultural Research (ACIAR). ACIAR Project Number 9304, Final Report, September 1995
23. Samoilys, MA, Squire, LC and Roelofs, A. (2001) Long term monitoring of coral trout spawning aggregations on the Great Barrier Reef: implications for fisheries management. Abstract - Indo Pacific Fish Conference, Durban, South Africa, May 2001.
24. Samoilys, MA and Carlos, G (1992) Development of an underwater visual census method for assessing shallow water reef fish stocks in the south west Pacific. ACIAR Project PN8545 Final Report, April 1992. 100pp.
25. Samoilys, M., Slade, S.J., and Williams, L.E. (2002a) Coral Trout. pp. 75-79. In: Williams, LE (ed.) Queensland's Fisheries Resources: Current Conditions and Recent Trends 1988-2000. Q102012. Department of Primary Industries Queensland, Brisbane. 182pp.
26. Samoilys, M, Williams, L. and Slade, S. (2002b). Coral reef line fishery. pp. 66-72. In: Williams, L.E. (ed.) Queenland's fisheries resources - Current condition and recent trends 1988-2000. Queensland Department of Primary Industries. Brisbane. 182pp.
27. SCRFA (2004). Fisher interviews (www.scrfa.org)
28. St John, J. (1999). Ontogenetic changes in the diet of the coral trout reef grouper Plectropomus leopardus (Serranidae): patterns in taxa, size and habitat of prey. Marine ecology progress series 180:233-246
29. Suwirya K. (2005) Spawning and larval rearing of coral trout at Gondol. SPC Live Reef Fish Information Bulletin. 13: 45
30. Turnbull, C.T., Samoilys, M.A. (1997). Effectiveness of spawning closures in managing the line fishery on the Great Barrier Reef. Report to the Reef Fish Management Advisory Committee of the Queensland Fisheries Management Authority. 24pp
31. Williams, A. J., Currey, L. M., Begg, Murchie, C.D. and Ballagh A.C. (in press) Population biology of coral trout species in the eastern Torres Strait: Implications for fishery management. Continental Shelf Research
32. Zeller, D.C. (1998). Spawning aggregations: Patterns of movement of the coral grouper Plectropomus leopardus (Serranidae) as determined by ultrasonic telemetry. Marine Ecology Progress Series 162:253-263
33. Zeller, D.C. and G.R. Russ (2000) Population estimates and size structure of Plectropomus leopardus (Pisces:Serranidae) in relation to no-fishing zones: mark-release-resighting and underwater visual census. Marine and Freshwater Research. 51: 221-228.

 

Black Grouper

m_bonaci3Photo: SeaPics

Mycteroperca bonaci

Description and Distribution

Mycteroperca bonaci (Black grouper) is a tropical species distributed in the western Atlantic: Bermuda and Massachusetts, USA to southern Brazil, including the southern Gulf of Mexico and the Caribbean. The species was referred to as Serranus bonaci in earlier literature.
M. bonaci is a commercial food fish with excellent flesh quality and high price value, despite some reported cases of ciguatera from human consumption. It has a distinctive dark body and fins with rectangular dark gray blotches at the sides. The grouper is commonly seen to 70 cm (TL) while the maximum reported length is 150 cm (TL) and weight is 100kg (4,8,9,11,13).

Preferred Habitat

The species is reef-associated and also found on rocky substrates, with depth ranges of 6 to 33 m. Its juveniles have been found in seagrass beds off the coast of Florida, USA (8,9,11).

m_bonaci_clip_image002Source: SCRFA
The above diagram shows the range of the black grouper (highlighted in green)
and reported spawning aggregation sites (highlighted in red)

 

Life History

M. bonaci is a large fish with a protruding lower jaw. It has an oblong body shape and olive or gray body colouration along with dark rectangular blotches. The species can live over 30 years, but most of the growth occurs during the first ten years of life. Adults feed primarily on other smaller reef fishes and crustaceans while juvenile feed solely on crustaceans) (4,11,14).

Black grouper is oviparous and protogynous hermaphrodite. At about ~100-120cm (TL), some of the population changes sex from female to male. The groupers are reproductively active from November through May, with vitellogenic oocytes and oocytes in the final stages of maturation most commonly found during January to March. A study indicated that 50% maturity of females was attained at 72.1cm (FL), while median size at sexual inversion was 103.3cm (FL), and 50% of the females had transformed into males at 111.4cm (FL) (1,3,4,5,15,16).

The grouper has several predators including sandbar sharks (Carcharhinus plumbeus), great hammerhead (Sphyrna mokarran), barracuda (Sphyraena barracuda) and moray eels. It also has several common parasites all of which affect the stomach and intestines, including trematodes, cestodes, and nematodes (11,13,14).


Spawning Aggregations

Aggregations have been reported from most of the range of the black grouper, including from the Bahamas, Belize, Cayman Islands, Cuba, and Southeastern USA. The species in the Gulf of Mexico and Caribbean Sea form spawning aggregations in winter (December to March). Fish residing in the northeastern of Brazilian coast aggregate to spawn from April to September and also aggregate to feed (a phenomenon named "correcão" in Portuguese during winter). During "correcão", black grouper takes advantage of spawning aggregations of other species to feed on them. The species was observed to aggregate at reef promontory, and outer reef slopes. There are reports of spawning aggregations on different lunar days with no consistent lunar pattern noted for spawning (1,3,6,7,14,15,19).

m_bonaci_ushioda_seapics Photo: Seapics

Fisheries

M. bonaci is marketed fresh and its flesh is valuable and of excellent quality. It is a common commercial and recreational fish, easily one of the most sought-after species in the region. The black grouper is usually sold fresh and iced; a small fraction of them are filleted and frozen (whole fish). There have been reported cases of ciguatera poisoning.

Both recreational and commercial fishing of black grouper occur. Recreationally, people sail in ‘party' boats, and fish using fishing rods and reels, sometimes electric reels; or spear fishers fish with SCUBA diving gear. Commercially, fishers catch black grouper mostly with handlines, but also use shrimp trawls, lobster traps, fish pots, seines, trammels & gill nets, and longlines.

The species supports an important fishery in the region. In the Yucatan, Mexico, the black grouper contributes up to 40% of the total weight of the commercial marine fish production. In South Florida, its commercial landings consistently exceed landings of any other grouper in the area, and are highest in winter when the gonadosomatic indices peak. However, the estimated value of the species being landed in Florida has declined from US$2.7M in 1990 to $1.1M in 1996.

The black grouper is an important species for the demersal fisheries in the northeastern Brazilian coast, and is the most frequently caught serranid in the demersal bottom line fisheries in this area. The species is probably already undergoing overfishing effects, as the capture of the black grouper has decreased the last two decades.
(7,8,10,15,17,18,19)

Mariculture

No information. There is no research or commercial culture of the species.


Threats

The major threat to the black grouper is overfishing, in exacerbated because spawning aggregations are commonly targeted. For example, in Bermuda the rapid development of trap fishing on grouper populations in shallow waters in the 1980s led to decrease in grouper catches over a period of seven years; the decrease was from 40,000 kg/yr to 68,000 kg/yr for the black grouper: a six-fold reduction.

The black grouper is a commercially important species in Florida but its total landing value declined by more than half in 6 years. Fishery data indicated that large grouper are still abundant in deeper and more remote areas, while they rarely appear in shallow waters adjacent to normal fishing grounds.

Overfishing is also reported in Brazil and Mexico.
(2,7,8,12,18,19)


Conservation & Management

M. bonaci is commonly landed in commercial grouper fisheries in the Gulf of Mexico and the south Atlantic Ocean, where some countries regulate the trade by imposing size limits (minimum size limits). The species is also protected by several marine protected areas (MPA) within its range. However, the stress on the species is high because it isheavily fished throughout its range and the effectiveness of MPA protection is not known. Moreover, spawning and feeding aggregations commonly targeted; and nursery areas affected by sedimentation. The species is listed as ‘near threatened' in the IUCN red list. It is regarded as vulnerable to fishing and to have a low resilience to fishing pressure.

In order to conserve black grouper, the government of Florida has imposed regulations on both recreational (50 cm TL and daily catch limits) and commercial (50 cm TL and annual quota) fishing. Nonetheless, this restriction will affect the species due to its hermaphroditic nature, which makes it more sensitive to size-selective fishing, skewing populations towards females, in turn possibly affecting spawning success if male numbers become too low. Studies indicate that mature males and females are found in size classes from 60-130 cm (FL), and minimum size limits should hence be set accordingly.

Mexico is also facing a similar situation as noted in Florida. The species is considered to be highly vulnerable to fishing, and, because of its biological characteristics, black grouper should be carefully managed to avoid rapid overfishing and stock collapse. Therefore, conservation and management efforts should incorporate the biology of the target species (especially reproduction). For instance, a minimum size limit at which 50% of the females are sexually mature (i.e. around 75cm FL), and closed season during peak spawning aggregations.

The black grouper is now effectively protected inside the Florida Keys National Marine Sanctuary. The spawning aggregations sites observed have now been included in the reserve boundary, incorporating the needs and biology of the species.
(7,8,9,10,15,17,18,19)

 

References

1. Allsop, D.J. & West S.A (2003) Constant relative age and size at sex change for sequentially hermaphroditic fish. Journal of Evolutionary Biology 16:921-929.
2. Bannerot et al (1987) Reproductive strategies and the management of tropical snappers and groupers. In Tropical snappers and groupers: biology and fisheries management, pp. 561-603. Boulder: Westview Press.
3. Brulé et al (2003) Reproduction in the protogynous black grouper (Mycteroperca bonaci (Poey)) from the southern Gulf of Mexico. Fisheries Bulletin 101: 463-475.
4. Brulé et al (2005) Diet composition of juvenile black grouper (Mycteroperca bonaci) from coastal nursery areas of the Yucatan peninsula, Mexico. Bulletin of marine science, 77(3): 441-452.
5. Crabtree, R.E. & Bullock, L.H. (1998) Age, growth, and reproduction of black grouper, Mycteroperca bonaci, in Florida waters. Fisheries Bulletin 96((4)): 735-753.
6. Domeier, M.J. & Colin, P.L. (1997) Tropical reef fish spawning aggregations: defined and reviewed. Bulletin of Marine Science 60: 698-726.
7. Eklund, A.M. et al (2000) Black grouper aggregation in relation to protected areas within the Florida Keys National Marine Sanctuary. Bulletin of Marine Science 66: 721-728.
8. Ferreira, B.P. et al (2008). Mycteroperca bonaci. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. <www.iucnredlist.org>.
9. Fishbase (2009) http://www.fishbase.org/Summary/SpeciesSummary.php?id=1209
10. Florida keys national marine sanctuary (2007) State of the sanctuary report. http://sanctuaries.noaa.gov/sos2006/floridakeys.html
11. Ford T. (2009) Biological profile of black grouper. http://www.flmnh.ufl.edu/fish/Gallery/Descript/BlackGrouper/BlackGrouper.html
12. Fredou et al (2006) A univariate and multivariate study of reef fisheries off northeastern Brazil. Journal of Marine Science 63: 883-896.
13. Heemstra, P.C. & Randall, J.E. (1993) FAO species catalogue. Vol. 16. Groupers of the world (family Serranidae, subfamily Epinephelinae). An annotated and illustrated catalogue of the grouper, rockcod, hind, coral grouper and lyretail species known to date. ftp://ftp.fao.org/docrep/fao/009/t0540e/t0540e00.pdf
14. Jory, D.E. & Iversen, E.S. (1989) Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (south Florida). Black, red, and Nassau groupers.
15. Renan X. et al (2001) Preliminary results on the reproductive cycle of the black grouper from the Southern Gulf of Mexico. Proceedings of the 52nd Gulf and Caribbean Fisheries Institute. http://nsgl.gso.uri.edu/flsgp/flsgpw99004/flsgpw99004_part1.pdf
16. Sluka R. et al (1998) Density, species and size distribution of groupers (Serranidae) in three habitats at elbow reef, Florida Keys. Bulletin of marine science 62(1): 219-228.
17. Sluka R. et al (2001) Influence of habitat on grouper abundance in the Florida Keys, U.S.A. Journal of fish biology 58: 682-700.
18. Sluka R. & Sullivan K.M (1998) The influence of spear fishing on species composition and size of groupers on patch reefs in the upper Florida Keys. Fishery bulletin 96: 388-392.
19. Teixeira, S.F. et al (2004) Aspects of fishing and reproduction of the black grouper Mycteroperca bonaci (Poey, 1860) (Serranidae: Epinephelinae) in the Northeastern Brazil. Neotropical Ichthyology 2(1): 19-30.