Mutton Snapper

Mutton SnapperPhoto: Jack Randall (Fish Base) 

  

Lutjanus analis 

Description and Distribution

Mutton snapper, or king snapper, is distributed in the western Atlantic, ranging from United States south to Brazil including Bermuda, the Gulf of Mexico, and the Caribbean.  It occurs on the continental shelf areas as well as in clear waters around islands. The species forms small aggregations or schools which disband during the night. It feeds both day and night on fishes, shrimps, crabs, cephalopods, and gastropods. Mutton snapper has an average length of 50 cm (FL), while the maximum size can reach 94.0 cm TL (male) and 15.6 kg in weight. The maximum recorded age is 40 years. The species is listed as "vulnerable" on the IUCN red list (assessed in 1996) (1,3,12,14,18).

Preferred Habitat

L. analis is found most commonly over vegetated sand bottoms, in bays and estuaries and along mangrove coasts.  It also occurs around coral reefs, with large adults usually seen among rocks and coral, while juveniles occur over sandy and vegetated bottoms (1,3,8).

l_analis_rangeSource: SCRFA
The above diagram shows the range of the mutton snapper (highlighted in green)
and reported spawning aggregation sites (highlighted in red)

Life History

The mutton snapper has a distinct black spot on the upper back and blue stripes on the cheek region below the eye. It shows both plain and barred colour phases, with olive green on its back and upper-side and a red tinge on the lower side and underside. It is a relatively deep-bodied fish, with an almost lunate-shaped tail. It has a moderately bi-lobed dorsal fin, and a sharply pointed anal fin. The pectoral fin is long, reaching just past the anal origin.
Mutton snappers are active diurnally and nocturnally. The feeding habits of mutton snapper change during its life. Larval snapper feeds on plankton near the surface of water; as it settles out into shallow grass beds, it begins to feed on larger plankton and small invertebrates. The diet then switches to shrimps, snails, crabs, and small fishes including mullets and small grunts.
Like many snapper species, eggs of mutton snapper are pelagic and are hatched after approximately 20 hours.  At lengths of less than 10 mm, the larvae tend to be planktonic. They can be found in both brackish and marine waters at depths of 25-95 m. Juveniles are most common in inshore waterways where the substrate consists of sand, seagrass, or coral rubble.  Adults are typically found in deeper waters, at depths of 40 - 70 m, where they often form small schools during daylight hours, but disband at night.  Adults tend to remain in an area once they have become established and are most common in the open waters of shelf areas and around islands.  Larger adults inhabit coral reefs and rocky, hard bottom areas.
Male mutton snappers reach sexual maturity at about 38 to 43 cm (FL) while female snappers mature at about 45 to 47 cm (FL). The species is a gonochorist (i.e. separate sexes throughout life).
(1,3,4,7,8,9,11,12,14,16,18,20,21,22)


Spawning Aggregations

As with most larger snappers, L. analis spawns offshore in groups in which spawning typically occurs in summer.  The snapper is a solitary species, and rarely seen in groups outside of the spawning season. The snapper spawns throughout their range, though most record is obtained in the north-eastern Caribbean. They form large, transient aggregations in which spawning may last for several weeks in a month for several months each year. Spawning aggregations occur from April to September, at outer reef slopes, and on reef promontories and drop-offs. Mutton snapper exhibit high site-fidelity, spawning at the same site and on the same lunar calendar days (during full moon or in the third lunar quarter), year after year. The snapper is oviparous, releasing pelagic eggs that move freely with the water currents. As is typical of pelagic spawners, the number of eggs is dependent upon the size of the female, with larger fish containing more eggs. After spawning, the adult fish moves offshore to deeper waters (4,5,6,13,23).

Mutton Snapper 2Photo:Robert Patzner (Fish Base)

Fisheries

L. analis is highly commercial, and targeted as game fish and for aquarium trade. The flesh is marketed fresh and frozen, providing exceptionally good quality fish meat. It is often labelled as "red snapper". Mutton snapper is a wary fish, battles hard on the line and can be a very challenging game fish. Main methods of capture include boat seines, gill nets, bottom longlines, handlines, traps, and spearfishing by divers. Spawning aggregations are targeted by commercial fishers, contributing to around 50% of the total catch of the species in some areas. The species was once the major commercial snapper catch. However, its population in the wild has decreased recently, resulting in a decline in commercial fisheries. In Puerto Rico, FAO data reports a three-fold decline in mutton snapper catch, from 60 -70 tonnes in the late 1990s to 21 tonnes in 2007 (2,4,8,10).
In Cuba, mutton snapper contributes around 4% of the total commercial finfish catch, being one of the most valuable demersal fishes in the country. The species is mainly caught by seine, but during the spawning season, hook and line and set nets are also applied. The maximum catches are obtained in May to June, during the peak spawning aggregation season. A large proportion of immature individuals are caught in Cuba and Jamaica, before they are able to spawn, hence exerting significant stress onto the populations (7,21).
A study on catch-per-unit-effort (CPUE) of mutton snapper was conducted in Puerto Rico. The study analyzed fisheries data from 1989-2005. Over the period of assessment, the fishery CPUE value was fairly stable in the early years (up to 2000) and peaked at 2003 with a decline thereafter.  A similar study in Belize also reported a declining trend of inter-seasonal catch, effort and yield, with a decrease in mean landings per boat (8,9,13).

Mariculture

Mutton snapper has been spawned and raised in captivity. The species is maricultured by hatchery-rearing in net cages experimentally in Bahamas and Florida (2,24).

Threat

Marked declines have been recorded in mutton snapper populations in fisheries in a number of locations suggesting that the species may be widely overfished. A significant decline in lengths and weights has also observed in Belize, Florida and Puerto Rico (8,9,13).
Mutton snappers are known to form spawning aggregations with a high degree of site fidelity. A number of the aggregation sites have been heavily exploited by commercial fisheries during the last few decades throughout the range. As localized aggregations may be intensively exploited until they cease to form, such fishing potentially impairs recruitment (2,14,21).
In Cuba, many of the mutton snappers have not matured at the time of the catch. Due to their relatively large size of sexual maturation (around 50cm (TL)), establishing a minimum catch size that allows individuals to spawn at least once is difficult. Also, fishing gears to catch mutton snapper are usually non-selective, and applied in multispecies fisheries in which smaller-sized fishes dominate (6,7).

Conservation & Management

Mutton snapper is listed as "vulnerable" on the IUCN red list (assessed in 1996). Various studies indicated that the population of the species is declining, with moderate to high vulnerability and low resilience to fishing pressure. The species is currently protected by some marine protected areas (see below for their effectiveness), limited fishing gear types, and spawning season sales bans (5,12,14,15).                        
In Belize, the mutton snapper is targeted especially at spawning aggregations which has resulted in declines in CPUE and smaller fish size among catches. The spawning aggregation sites are being protected by two marine reserves but problems like poaching and ineffective management exist.  Therefore, a combined approach to rectify the situation, including a reproductive seasonal catch closure, and large-scale, actively enforced, no-take MPAs incorporating reproductive migratory pathways, are proposed(13).

In November 2005, the U.S. government implemented an amendment to the fishing regulation of snapper and grouper fisheries in the south Atlantic by imposing a 30 cm (TL) minimum size limit, seasonal closure during the spawning season in May and June, and restrictions on certain destructive fishing methods. In the U.S. Caribbean, other management regulations include the prohibition of possession of the species and fishing on spawning aggregation areas during summer (April to June) (7,16,22).

A two-month spawning season closure has been initiated since 1992 in Florida. However, such closures simply shift the commercial fishing effort to months on either side of the period, resulting in an increased total annual harvest of mutton snappers and reduced landings during part of the spawning months. The intent of the regulations, to protect spawning fish, was therefore not achieved. An ecological reserve was, therefore, created to specifically protect the spawning aggregations and the habitat of mutton snappers by prohibiting all uses within the reserve, except continuous transit through the reserve for research purposes. A research study monitoring the population inside the reserve found out that over 4 years, spawning aggregations have begun to re-form, showing an increase in number of fish (4,5).

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. Benetti D.D. et al (2002) Growth, survival, and feed conversion rates of hatery-reared mutton snapper Lutjanus analis cultured in floating net cages. Journal of the world aquaculture society 33(3): 349-357.
3. Bortone S.A. & Williams J.L. (1986) Species profile: gray, lane, mutton, and yellowtail snappers. http://library.fgcu.edu/caloo/sp1152.pdf
4. Burton, M.L. (2002) Age, growth and mortality of mutton snapper, Lutjanus analis, from the east coast of Florida, with a brief discussion of management implications. Fishery research 59(1-2):2002.
5. Burton, M.L. et al. (2005) Preliminary evidence of increased spawning aggregations of mutton snapper (Lutjanus analis) at Riley's Hump two years after establishment of the Tortugas South Ecological Reserve. Fishery Bulletin 103(2):404-410.
6. Claro R. & Lindeman K.C. (2003) Spawning aggregation sites of snapper and grouper species (Lutjanidae and Serranidae) on the shelf of cuba. Gulf and Caribbean research 14(2): 91-106.
7. Claro R. et al. (2001) Ecology of the marine fishes of Cuba. Smithsonian institution. 253p.
8. Cummings, N. (2007) An examination of the mutton snapper, Lutjanus analis, commercial catch per unit of effort data in Puerto Rico from 1983-2005 available for use in developing estimates of abundance. SEDAR-14 Assessment Workshop Report No-1. 44p.
9. Cummings, N. (2007) Important Aspects of the life history of mutton snapper, Lutjanus analis, with emphasis on populations in the Caribbean. SEDAR-14 Assessment Workshop Report No-2. 12p.
10. Cummings, N. & Matos-Caraballo D. (2007) Information on commercial removals of the mutton snapper, Lutjanus analis, in Puerto Rico from 1983 through 2005 and trends in nominal catch per unit of effort. SEDAR 14 Data Workshop Report No. 7. 40p.
11. Duarte, L.O. & Garcia C.B. (1999) Diet of the mutton snapper, Lutjanus analis (Cuvier) from the Gulf of Salamanca, Colombia, Caribbean Sea. Bulletin of marine science 65(2):453-465.
12. Fishbase (2009) http://www.fishbase.org/Summary/SpeciesSummary.php?id=1403
13. Graham R.T. et al. (2008) Historical and contemporary evidence of a mutton snapper (Lutjanus analis Cuvier, 1828) spawning aggregation fishery in decline. Coral Reefs 27:311-319.
14. Huntsman, G. (1996) Lutjanus analis. In: IUCN 2009. IUCN red list of threatened species. http://www.iucnredlist.org.
15. Lindeman, K.C. et al. (2000) Developmental patterns within a multispecies reef fishery: management applications for essential fish habitats and protected areas. Bulletin of marine science 66(3):929-956.
16. 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
17. Matos-Caraballo, D. (2004). Historical landings and biostatistical CFSP data analysis for five important species. Portrait of the fishery of mutton snapper, Lutjanus analis, in Puerto Rico during 1988-2001. http://www.sefsc.noaa.gov/sedar/download/S14SAR2%20Mutton%20Report.pdf?id=DOCUMENT
18. Murray R. & Bester C. (2009) Biological profile of mutton snapper.
http://www.flmnh.ufl.edu/fish/Gallery/Descript/MuttonSnapper/MuttonSnapper.html
19. Monteiro-Neto, C. et al. (2003) Analysis of the marine ornamental fish trade at Cear√° State, northeast Brazil. Biodiversity conservation 12:1287-1295.
20. Muller K.W. (1995) Size structure of mutton snapper, Lutjanus analis, associated with unexploited artificial patch reefs in the central Bahamas. Fisheries Bulletin 93: 573-576.
21. Munro J.L. (1983) Caribbean Coral Reef Fishery resources. ICLARM studies and reviews 7, 276p.
22. NOAA (2005) Stock assessment and fishery evaluation report for the snapper and grouper fishery of the south Atlantic. http://ocean.floridamarine.org/efh_coral/pdfs/SnapperGrouperSAFE111805.pdf
23. Paris, C.B. et al (2005) Larval transport pathways from Cuban snapper (Lutjanidae) spawning aggregations based on biophysical modeling. Marine ecology progress series 296: 93-106
24. Watanabe W.O. et al (1998) Artificial propagation of mutton snapper Lutjanus analis, a new candidate marine fish species for aquaculture. Journal of the World Aquaculture Society 29(2): 176-187