Dermatolepis inermis 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Actinopterygii Perciformes Epinephelidae

Scientific Name: Dermatolepis inermis (Valenciennes, 1833)
Regional Assessments:
Common Name(s):
English Marbled Grouper, Donkey Fish, Mutton Hamlet, Rockhind, Sickelfish Grouper
French Merou Marbre
Spanish Boricua, Cherna Jaspeada, Mero, Mero Marmal, Mero Tigre, Viuda
Dermatolepis inermis (Valenciennes, 1833)
Serranus inermis Valenciennes, 1833

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2008
Date Assessed: 2008-01-01
Assessor(s): Rocha, L., Ferreira, B., Choat, J.H., Craig, M.T., Sadovy, Y., Bertoncini, A.A. & Sampaio, C.
Reviewer(s): Craig, M., Sadovy, Y. & Bertoncini, A. (Grouper and Wrasse Red List Authority)
Dermatolepis inermis is listed as Near Threatened (NT) because although it is very widespread and has a large depth range it is a rare species, and apparently may only be found in part of that range now. It is subjected to fishing pressure including very probably on spawning aggregations. Given problems associated with aggregation fishing, and the rarity of the species and indications of past declines, for a species that is relatively rare in a group of fish considered to be good for eating, the species should be considered as NT.
Previously published Red List assessments:

Geographic Range [top]

Range Description:Dermatolepis inermis is a western Atlantic species ranging from North Carolina (USA) to Venezuela, including the Gulf of Mexico and the Caribbean. A separate range exists from northern Brazil to Rio de Janeiro, including the off-shore islands.
Countries occurrence:
Anguilla; Antigua and Barbuda; Aruba; Bahamas; Barbados; Belize; Bermuda; Bonaire, Sint Eustatius and Saba (Saba, Sint Eustatius); Brazil (Alagoas, Bahia, Ceará, Espírito Santo, Paraíba, Pernambuco, Rio de Janeiro, Rio Grande do Norte, São Paulo, Sergipe, Trindade); Cayman Islands; Colombia; Costa Rica; Cuba; Curaçao; Dominica; Dominican Republic; French Guiana; Grenada; Guadeloupe; Guatemala; Guyana; Haiti; Honduras; Jamaica; Martinique; Mexico (Campeche, Quintana Roo, Tabasco, Veracruz, Yucatán); Montserrat; Nicaragua; Panama; Puerto Rico; Saint Kitts and Nevis; Saint Lucia; Saint Martin (French part); Saint Vincent and the Grenadines; Sint Maarten (Dutch part); Suriname; Trinidad and Tobago; Turks and Caicos Islands; United States (Alabama, Florida, Georgia, Louisiana, North Carolina, South Carolina, Texas); Venezuela, Bolivarian Republic of; Virgin Islands, British; Virgin Islands, U.S.
FAO Marine Fishing Areas:
Atlantic – western central; Atlantic – southeast
Additional data:
Lower depth limit (metres):213
Upper depth limit (metres):3
Range Map:Click here to open the map viewer and explore range.

Population [top]

Dermatolepis inermis is relatively rare throughout its range and rarely seen in markets.

There are very few studies for this Atlantic species. D. inermis is scarce in catches from US waters or apparently elsewhere (Heemstra and Randall 1993, Huntsman et al 1999).

Fishery-independent Data
The Flower Garden Banks National Marine Sanctuary (FGBNMS) Research Team has conducted 187 remotely operated vehicle (ROV) surveys for a duration of 218 H 13 M between February 2001 and March 2007. The survey times ranged from 0.5 H to approximately 4 H at average depths of 68.5 m. Of these 187 surveys, 144 were conducted at the FGBNMS, located in the northwestern Gulf of Mexico. The remaining 43 were conducted at other shelf edge and mid shelf banks in the northwestern Gulf of Mexico, outside of the Sanctuary boundaries. During these surveys, 150 records of individual D. inermis were made. It is estimated, based on annotations and dive tracks that conservatively, 10% of these animals were repeat counts, leaving 135 records of individuals. The most animals seen in one location was nine individuals. Based on these observations and compared to other observations Caribbean wide, the reefs and banks of the northwestern Gulf of Mexico are hotspots for this species, although still at relatively low abundance levels. The majority of the observations are of adult-size animals (Table 1).

See the supplementary material for Table 1: records of D. inermis sighted on remotely operated vehicle (ROV) dives between February 2001 and March 2007.

This species was also sighted during manned submersible fish surveys in 2002. Six surveys were conducted between 19 and 90 meters depth for a duration of 28 H (Table 2).

See the supplementary material for Table 2: records from submersible dives targeting fishes in 2002.

During these submersible surveys, several juvenile D. inermis were filmed taking refuge in and around spines of sea urchin that were creating mounds on the sea floor.

In addition to these observations, unquantified sightings of D. inermis have been made by qualified SCUBA divers at Stetson Bank, East and West Flower Garden Banks and at Bright and Geyer Banks (source: Emma Hickerson, P.P. Schmahl, Flower Garden Banks NMS, Galveston, Texas).

The Reef Environmental Education Foundation (REEF)’s Fish Survey Project ( allows volunteer SCUBA divers and snorkelers to collect and report information on marine fish populations in the USA from 1993 to present. Throughout the sampling period 1993 to 2005, it seems that the sighting frequency of D. inermis could be regarded as a rare species (<0.6% of all surveys) (Table 3).

See the supplementary material for Table 3: sighting frequency estimates collected by volunteer divers and snorkelers (1993-2005) by the Reef Environmental Education Foundation (REEF).

A recreational fishing charter (head boat) operator, Captain Elliot’s, out of Freeport, Texas, confirmed landing 67 D. inermis between August 23-25 2006. Due to the large number of fish, this could possibly represent the only known spawning aggregation. The location of the catch was not reported specifically, but as on the shelf edge banks off the coast of Louisiana. This corresponds to the shelf edge banks in the vicinity of the Flower Garden Banks NMS. (NOAA Fisheries, Pascagoula, MS SEAMAP Data; source: Christopher Gledhill and Kevin Rademacher, NOAA Fisheries, Pascagoula, MS).

In drop-camera surveys conducted in the northwestern Gulf of Mexico from 1992 to 1997, 2001, and 2004 to 2005, over a duration of 1,260 hours 44 minutes of video, a total minimum count of sixty six (66) D. inermis was documented. "Mincount" is the minimum count (see MAXNO in Ellis and DiMartini 1995), the largest number of fish observed in a single frame of video. Mincount was not available for 1992, however it can be estimated that a further three animals were present.

Chris Koenig (PhD. Reef Fish Ecology Group, Florida State University Coastal and Marine Laboratory) gives the following expert personal assessment of the species: the species is “rare almost everywhere; the only place where we find them is in the western Gulf of Mexico Banks, and they are being systematically fished out. I spoke with fish collectors in the Fla Keys, including Billy Causey in his former life, and they say that they don't see them anymore, but did in the distant past. I consider this fish similar to the ivory-billed woodpecker, never abundant, but existing now only in small pockets".

Fishery-dependent Data
Dermatolepis inermis represented only 2.5 % of the total weight recorded during a survey using long-line in the shelf break in the Central coast of Brazil, with a maximum catch rate of 2.6 kg per 1,000 hooks in the 100 to 300 depth.

Gulf of Mexico region
According to NMFS annual landings of commercial catches in the USA from 1986 to 2004, the quantity caught ranged from 0.4 in 1987 to 19.7 metric tonnes in 1993. From 1999 to 2004, the average annual landings were less than 1.4 metric tonnes (, accessed on 5th Jan 2006) (Table 4).

See the supplementary material for Table 4: commercial catch estimates from the National Marine Fisheries Service (NMFS) from 1986 to 2004.

According to NMFS’s annual harvest estimates from 1981 to 2004, a total number of 7,891 fish (8,955+ lbs) were caught for recreational purpose. (Note: there are very large proportional standard errors associated with the annual estimates of landings by number, which suggest these are rare-event landings in the recreational fisheries of the Gulf of Mexico). (Tom Sminskey pers. comm., 10th Jan 06) (Table 5).

See the supplementary material for Table 5: recreational catches of D. inermis between 1981 and 2004.

Head boat landings collected by NOAA Fisheries, Beaufort, since 1986 report D. inermis landings from headboats originating from two areas in Texas (see Table 6).

See the supplementary material for Table 6: head boat landing statistics from Areas 25 (Sabine Pass to Freeport, TX) and Area 26 (Pt. Aransas, TX) between 1995 and 2006.

The increased level of landings in 2006 suggests extraction from a spawning aggregation.
For further information about this species, see 39303_Dermatolepis_inermis.pdf.
A PDF viewer such as Adobe Reader is required.
Current Population Trend:Decreasing
Additional data:
Population severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:Dermatolepis inermis is a reef-associated species usually found on deep ledges, at depths to 210 m and on reefs, usually in caves or deep crevices. Marbled grouper are solitary and secretive, but presumably form spawning aggregation like other species of the genus.
Congregatory:Congregatory (and dispersive)

Threats [top]

Major Threat(s): Dermatolepis inermis is threatened by overfishing both as adults within the commercial and recreational fishery and as juveniles by the aquarium trade, including on spawning aggregations.

Conservation Actions [top]

Conservation Actions: Dermatolepis inermis is present in marine protected areas in some parts of its range. More information is needed on potential spawning aggregation sites and, once located, protection should be afforded these areas.

D. inermis was included on the Red List of the IUCN in 1996. Marbled grouper were classified as vulnerable by the American Fisheries Society based on the U.S. Fish and Wildlife Service (USFWS)’s concept of District Population Segments (DPS) (Musick et al 2000).

Classifications [top]

9. Marine Neritic -> 9.2. Marine Neritic - Subtidal Rock and Rocky Reefs
9. Marine Neritic -> 9.8. Marine Neritic - Coral Reef -> 9.8.1. Outer Reef Channel
9. Marine Neritic -> 9.8. Marine Neritic - Coral Reef -> 9.8.2. Back Slope
9. Marine Neritic -> 9.8. Marine Neritic - Coral Reef -> 9.8.3. Foreslope (Outer Reef Slope)
2. Land/water management -> 2.1. Site/area management

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
  Occur in at least one PA:Yes
In-Place Species Management
In-Place Education
5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.1. Intentional use: (subsistence/small scale) [harvest]
♦ timing:Ongoing    
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.2. Intentional use: (large scale) [harvest]
♦ timing:Ongoing    
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

1. Research -> 1.3. Life history & ecology

♦  Food - human
 Local : ✓   National : ✓ 

♦  Pets/display animals, horticulture
 National : ✓  International : ✓ 

Bibliography [top]

Heemstra, P.C. and 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. FAO, Rome.

Huntsman, G.R., Potts, J., Mays, R.W. and Vaughan, D. 1999. Groupers (Serranidae, Ephinephelinae): endangered apex predators of reef communities.

IUCN. 2008. IUCN Red List of Threatened Species. Available at: (Accessed: 5 October 2008).

Musick, J.A., Harbin, M.M., Berkeley, S.A., Burgess, G.H., Eklund, A.M., Findley, L., Gilmore, R.G., Golden, J.T., Ha, D.S., et al. 2000. Marine, estuarine, and diadromous fish stocks at risk of extinction in North America (Exclusive of Pacific Salmonids)..

Citation: Rocha, L., Ferreira, B., Choat, J.H., Craig, M.T., Sadovy, Y., Bertoncini, A.A. & Sampaio, C. 2008. Dermatolepis inermis. The IUCN Red List of Threatened Species 2008: e.T39303A10186064. . Downloaded on 24 October 2017.
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