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Abstract

Epinephelus marginatus is a widely distributed species that inhabits rocky reef habitat. Its globalpopulation is comprised of at least four mostly separated subpopulations. It has been heavily targetedby recreational and commercial fishers, especially in the European/Mediterranean portion of its range,for hundreds of years. As a result, its population is known to be greatly reduced in certain areas, andimmature individuals are now increasingly also taken. Landings data for this species are reportedannually to FAO by some countries, particularly southern Europe and the Mediterranean and parts ofnorthwestern Africa, but to a much lesser extent in southeastern Africa and southeastern SouthAmerica. When aggregated on a global level, landings have declined by about 86% over the past 24years (from 1992-2016). Reliable data are mostly limited in most of its four subpopulations, especially trends in fishing effort, but it remains a highly-valued species throughout its range, and it is unlikelythat fishing effort for it would have been voluntarily reduced.
The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2008: T7859A100467602
Scope: Global
Language: English
Epinephelus marginatus, Dusky Grouper
Assessment by: Pollard, D.A., Afonso, P., Bertoncini, A.A., Fennessy, S., Francour,
P. & Barreiros, J.
View on www.iucnredlist.org
Citation: Pollard, D.A., Afonso, P., Bertoncini, A.A., Fennessy, S., Francour, P. & Barreiros, J. 2018.
Epinephelus marginatus. The IUCN Red List of Threatened Species 2018: e.T7859A100467602.
http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
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THE IUCN RED LIST OF THREATENED SPECIES™
Taxonomy
Kingdom Phylum Class Order Family
Animalia Chordata Actinopterygii Perciformes Epinephelidae
Taxon Name:ÊÊEpinephelus marginatus (Lowe, 1834)
Synonym(s):
Epinephelus guaza (Linneaus, 1758)
Serranus aspersus Jenyns, 1840
Serranus marginatus Lowe, 1834
Regional Assessments:
• Mediterranean
• Europe
Common Name(s):
• English: Dusky Grouper, Yellowbelly Grouper, Yellowbelly Rockcod
• French: Méerou Brun
• Spanish: Mero Moreno
Taxonomic Source(s):
Craig, M.T. and Hastings, P.A. 2007. A molecular phylogeny of the groupers of the subfamily
Epinephelinae (Serranidae) with a revised classification of the Epinephelini. Ichthyological Research
54(1): 1-17.
Taxonomic Notes:
Based on molecular phylogenetic analysis, Craig and Hastings (2007) consider the species Epinephelus
marginatus to be a member of genus Mycteroperca.
Assessment Information
Red List Category & Criteria: Vulnerable A2bd+4bd ver 3.1
Year Published: 2018
Date Assessed: November 20, 2016
Justification:
Epinephelus marginatus is a widely distributed species that inhabits rocky reef habitat. Its global
population is comprised of at least four mostly separated subpopulations. It has been heavily targeted
by recreational and commercial fishers, especially in the European/Mediterranean portion of its range,
for hundreds of years. As a result, its population is known to be greatly reduced in certain areas, and
immature individuals are now increasingly also taken. Landings data for this species are reported
annually to FAO by some countries, particularly southern Europe and the Mediterranean and parts of
northwestern Africa, but to a much lesser extent in southeastern Africa and southeastern South
America. When aggregated on a global level, landings have declined by about 86% over the past 24
years (from 1992-2016). Reliable data are mostly limited in most of its four subpopulations, especially
© The IUCN Red List of Threatened Species: Epinephelus marginatus – published in 2018.
http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
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on trends in fishing effort, but it remains a highly-valued species throughout its range, and it is unlikely
that fishing effort for it would have been voluntarily reduced.
The four subpopulations are summarized as follows:
Northeast Atlantic/Mediterranean: recorded declines in landings averaging 88% over the past
generation length (estimated as 33.75 years); some recovery in abundance is occurring where fishing
effort has been significantly reduced (e.g., northern Mediterranean);
West Africa: lack of data makes status poorly understood, but grouper fisheries do exist in the region,
so the potential for declines is possible;
Southwestern Indian Ocean: apparently overexploited in South Africa at least in the late 1990s and
status elsewhere in the region not well known;
Southwestern Atlantic: significant declines in landings over the past 10 to 15 years across southern
Brazil and status elsewhere in the region not well known. In addition, fishing is expected to continue,
and has been recently increasing in some areas.
This species also has a high intrinsic vulnerability to overfishing due to protogynous hermaphroditism,
aggregate spawning behaviour and slow growth. There is evidence for some localised recovery in certain
protected areas with no-take zones mainly in the Northeast Atlantic/Mediterranean portion of its range,
including in French waters where a complete fishing ban for this species has been in place since at least
2003. Quantitative data are insufficient to estimate population trends over a three generation length
period (about 101 years); however, considering that the majority of the global population of this species
is within the Northeast Atlantic/Mediterranean subpopulation, which has experienced serious declines
exceeding 80% over the past generation length and probably more, and given anecdotal reports of
serious declines expected to continue into the future elsewhere in its range, we believe a precautionary
approach that suspects a global-level decline of at least 30-50% over the next two generation lengths is
appropriate. Considering the uncertainty in the data, it is conservatively listed as Vulnerable A2bd+4bd.
Further research is needed on its population status, especially in the southwestern Indian Ocean, the
southwestern Atlantic and West Africa, and actions that reduce fishing effort are greatly needed. The
change in status from the previous assessment reflects an improved application of the IUCN Red List
Categories and Criteria, as well as a better understanding of available data.
Previously Published Red List Assessments
2004 – Endangered (EN)
http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T7859A12857009.en
1996 – Lower Risk/near threatened (LR/nt)
Geographic Range
Range Description:
This species is distributed in the northeastern Atlantic Ocean from the southern English Channel, south
along the coasts of western Spain and Portugal, throughout the Mediterranean Sea and Macaronesian
islands and south along West Africa to southern Angola and possibly northern Namibia at the Cunene
River (H. Holtzhausen pers. comm. 2016). It also occurs in the Western Indian Ocean from western
South Africa (C. Attwood pers. comm. 2016) to southern Mozambique, southeastern Madagascar (25°S,
47°E; P. Heemstra unpub. data, S. Fennessy pers. obs. 2013) and Reunion Island (Reid et al. 2016). In the
southwestern Atlantic Ocean, it is distributed from the mouth of the Rio Doce in the state of Espírito
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Santo in Brazil south to northern Patagonia in Argentina (Irigoyen et al. 2005, M. Borgonha pers. comm.
2016, Condini et al. 2016). Its depth range is zero to 300 metres.
In the past it has been recorded from the Sea of Marmara within the Mediterranean (Devedjian 1915 in
Bilecenoglu et al. 2002), but hasn't been recorded there since, and is absent from the Black Sea (Keskin
2010, M. Bilecenoglu pers. comm. 2016). In the northeastern Atlantic, there are few records north of
~45°N latitude, the northern-most being from the French coastline in the English Channel (49°21.5’N,
0°35’W; Mahé et al. 2012). In West Africa, it may be absent from parts of the Gulf of Guinea, but this still
requires confirmation (J.P. Barreiros pers. comm. 2016). Records from southern Oman (Randall 1995)
are probably waifs or misidentifications.
Country Occurrence:
Native: Albania; Algeria; Angola; Argentina; Benin; Bosnia and Herzegovina; Brazil; Cabo Verde;
Cameroon; Congo; Congo, The Democratic Republic of the; Côte d'Ivoire; Croatia; Cyprus; Egypt;
Equatorial Guinea (Annobón, Equatorial Guinea (mainland)); France (Corsica, France (mainland));
Gabon; Gambia; Ghana; Gibraltar; Greece; Guernsey; Guinea; Guinea-Bissau; Israel; Italy (Italy
(mainland), Sardegna, Sicilia); Jersey; Lebanon; Liberia; Libya; Madagascar; Malta; Mauritania; Monaco;
Montenegro; Morocco; Nigeria; Portugal (Azores, Madeira, Portugal (mainland), Selvagens); Réunion;
Senegal; Sierra Leone; Slovenia; South Africa; Spain (Baleares, Canary Is., Spain (mainland), Spanish
North African Territories); Syrian Arab Republic; Togo; Tunisia; Turkey; United Kingdom; Uruguay;
Western Sahara
FAO Marine Fishing Areas:
Native: Atlantic - southwest, Atlantic - southeast, Atlantic - northeast, Atlantic - eastern central, Indian
Ocean - western, Mediterranean and Black Sea -
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Distribution Map
Epinephelus marginatus
© The IUCN Red List of Threatened Species: Epinephelus marginatus – published in 2018.
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Population
This species occurs in at least four main separate/disjunct populations with minimal gene flow between
them: the northeastern Atlantic/Mediterranean, the southeastern Atlantic/West Africa, the
southwestern Indian Ocean and the southwestern Atlantic Ocean (Schunter et al. 2011). Population
information is available from some areas in its range from fishery landings and underwater surveys. In
shallower areas, underwater surveying is probably the most effective method for population estimation.
In the Mediterranean Sea, which is one of the main centres of its global population, landings data
indicate a serious and continuing decline. Some populations of this species (e.g., in Macaronesia and
probably also parts of southern Brazil) have apparently experienced a lesser impact from fishing
pressure than the Mediterranean and southern Europe population; however, these areas are likely to
represent a relatively small proportion of the overall global population in comparison to the
Mediterranean and northwestern Africa. There is a lack of adequate catch/population information from
some of its relatively wide distribution (e.g., South Africa, and parts of Brazil) which could be used to
determine any significant population trends in these areas. Populations around some of the
Macaronesian islands, and particularly the Azores (J.P. Barreiros pers. comm. 2016), although relatively
small, are considered to be relatively healthy compared with those found in mainland southern
European and Mediterranean waters, but may also be declining (Figure 1 in the Supplementary
Material).
According to total global landings reported to FAO from 1950 to the mid 2010s (mostly only reported at
the species level by European/Mediterranean countries), catch was about 200 metric tons in 1950 and
gradually increased over the subsequent 23 years to a peak of about 6,000 metric tons in 1973 (FishStatJ
database accessed 2015; Figure 2 in the Supplementary Material). Between 1975 and 1983, annual
landings declined to between 1,000 to 2,000 metric tons and then rapidly increased to peak at about
8,000 metric tons in 1992. These landings were primarily attributed to developing fisheries in the
Mediterranean. From 1993 onwards, global landings declined very rapidly to about 1,000 metric tons in
2015 and are expected to have since remained at that level. This represents an estimated decline of 86%
over the past 24 years (1992-2016), a period equivalent to about one generation length, and these
declines are considered to be ongoing. In addition, there was an estimated decline of ~88% over 10
years for southern Europe and the Mediterranean prior to 2001; and an even greater decline of ~94%
over 20 years using decadal averages for southern Europe for the period between 1984 and 2013.
Quantitative data are lacking in two out of the four subpopulations, but based on knowledge that
grouper fisheries are in significant decline in those areas, it is suspected that at least a 30-50% decline in
its global-level population has occurred over the past generation length (about 34 years; 1982-2016)
and is expected to continue into the future over the next two generation lengths, which is a time period
that extends to about 2083 (a total of 101 years).
Northeastern Atlantic and Mediterranean: According to archaeological sites in Spain, Tunisia, Corsica,
Cyprus, Sicily and Italy, this species was very abundant in the coastal systems between the 35th and
40th parallels, accounting for 30-80% of the examined bony remains until the end of the Mesolithic and
during the Neolithic eras (Desse and Desse-Berset 1999). A survey of ancient Greek, Etruscan and
Roman mosaics and paintings reported the depiction of large groupers being caught near the water’s
surface by fishermen using poles or harpoons from boats, techniques that would yield no grouper catch
today, which also supports the implication that abundance in coastal waters was high in the distant past
(Guidetti and Micheli 2011). In the northern Mediterranean, this species had not been reproductively
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active until relatively recently, probably due to an unbalanced sex-ratio (i.e., lack of males) caused by
fishing (Bodilis et al. 2003), but has also traditionally been more naturally abundant in the southern
Mediterranean (Echwikhi et al. 2014). However, increases in density, recruitment and reproductive
populations/spawning aggregations have been observed in the northwestern Mediterranean since
about 2010 (P. Lenfant and P. Francour pers. comm. 2016) due to an effective fishing moratorium along
the French Mediterranean coast. Individuals reported from the northeastern Atlantic at latitudes above
~45 degrees north are generally large and probably correspond to non-reproducing vagrants. In most of
Spain and Italy, this species is relatively abundant only in marine protected areas (MPAs) where fishing is
totally prohibited (La Mesa and Vacchi 1999, Guidetti et al. 2014, Barreiros 2015). There is evidence
from underwater surveys that this species may be undergoing recovery in several Mediterranean marine
protected areas where fishing is either restricted or banned (Vacchi et al. 1998, Harmelin-Vivien et al.
2008, Di Franco et al. 2009, Sala et al. 2012, Villamor and Becerro 2012, Garcia-Rubies et al. 2013,
Harmelin 2013, Guidetti et al. 2014).
According to FAO landings statistics, catch declined over the past 20 years in Italy by 98%, in Turkey by
78%, in Libya by 83%, in Greece by 28%, in Spain by 59% and in Portugal by 93% (FishStatJ database
accessed 2015; Figure 2 in the Supplementary Information). The targeted fishery for this species in
Turkey and Libya developed and peaked later than the fishery in Italy. The fishery in Spain and Portugal
peaked earlier than that in Italy. A decline has also more recently been observed in Tunisia and southern
Spain due to overfishing (Francour and Gratiot 2007); but no further details are available. Catches from
Libya currently comprise the majority of catch from the Mediterranean Sea, and around half of the
current global catch of this species. In the Azores archipelago, total catch fluctuated between 1978 and
2015, and generally declined after 2000 (Santos 2015).
West Africa: According to FAO landings statistics, Mauritania has reported four years of catch (from
2010 to 2013), that averaged ~66 metric tons per year. From 2003 to 2013, annual catch reported by
Senegal averaged ~123 metric tons, with no particular trend over time. Anecdotal reports claim large
commercial catches of this species were exported from southern Angola in the 1990s (S. Fennessy pers.
comm. 2016). In 2008, it comprised 2% of the artisanal catch in Namibe and Tombua, Angola (W. Potts
pers. comm. 2016).
Western Indian Ocean: This species is occasionally caught south to Knysna, South Africa (34°S, 23°E),
whereafter (i.e., westwards of there) it is increasingly uncommon. Specimens found to the south of 31°S
are reproductively inactive, and much smaller than those found further to the north along the east coast
of southern Africa (Fennessy 2006). Based on data collected in 1995-1997, spawning biomass per recruit
in the South African population had been reduced to ~30% of pristine levels and was considered
overexploited (Fennessy 2000). The only South African long-term data of grouper catch trends is from
largely unverified compulsory commercial catch records submitted by fishing boat skippers to the
national fisheries department, and these data were aggregated for all serranids (though four species,
including this one, were predominant in the catch). A substantial reduction in commercial fishing effort
occurred in 2003 as well as a reduction in the recreational bag limit and an increase in the minimum size
limit to 60 cm. Evidence of any recovery following these interventions was, however, not clear. Two
surveys conducted in the 1990s and 2000s recorded that this species comprised a relatively low portion
of catches in eastern South Africa. In southern Mozambique between 2002 and 2014, catch per unit
effort of this species in the semi-industrial line fishery varied between 0.5 and 8.7 kg/boat/per day, with
no significant trends over time. However, this fishery had commenced in earnest by the mid-1990s, and
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the contribution of this species to the overall catch is suspected to have declined since then (S. Fennessy
pers. comm. 2016; Figure 3 in the Supplementary Information).
Southwestern Atlantic Ocean: This species is targeted by artisanal fisheries and spearfishers from
Espírito Santo to Santa Catarina in southern Brazil (Andrade et al. 2003). It is also targeted by bottom
long-line fleets from Espirito Santo to Rio Grande do Sul in southern Brazil. No useful longer-term catch
data are available from this subpopulation, except for the Santa Catarina region of southern Brazil
(Figures 4 and 5 in the Supplementary Information). The Santa Catarina fishery developed over a ten-
year period from around 1988 (~25 metric tons) to 1998 (~75 metric tons), after which catches declined
by almost 99% to only ~1 metric tons by 2012 (about 15 years). The fishery in Sao Paulo is smaller, and
showed no particular trend, fluctuating between ~5 and ~25 metric tons between 1998 and 2015. In Rio
de Janeiro, catch data are only available from 2011 to 2014, during which total annual catch declined
from ~9.2 to ~6.4 metric tons. Catch per unit effort also declined from about 75 to 20 kg/trip between
2011 and 2014.
For further information about this species, see Supplementary Material.
Current Population Trend:ÊÊDecreasing
Habitat and Ecology (see Appendix for additional information)
This species inhabits rocky substrate to about 300 metres depth, but occurs in higher abundance to 50
metres (Bruslé 1985, Heemstra and Randall 1993, Reiner 1996, Harmelin and Harmelin-Vivien 1999,
Louisy 2005, Andrello et al. 2013). Post-metamorphic juveniles can be very common (and even
abundant) in tide pools during the first two weeks of September in the Azores (J.P. Barreiros and P.
Afonso unpub. data). It has a relatively small home range and high site fidelity (Maggs et al. 2013,
Oceanographic Research Institute unpublished data). It primarily feeds on fishes, crustaceans (mainly
crabs and lobsters) and cephalopods (mainly octopus) (Smale 1986). This species forms small spawning
aggregations of a few tens of individuals (Zabala et al. 1997a, b). In European waters, aggregation sites
have been observed in the Mediterranean Sea in the Medes Islands Marine Reserve, Spain (Zabala et al.
1997a, Hereu et al. 2006), off Lampedusa Island, Italy (Marino et al. 2001), in the National Park of Port-
Cros, France (Chauvet and Francour 1990) and in the Bouches de Bonifacio Marine Reserve, Corsica,
France (J.M. Culioli pers. comm. 2016); and in the Atlantic Ocean at the Azores Islands (Barreiros 1998,
Barreiros and Santos 1998) and probably elsewhere in the Macaronesian islands and southern mainland
Portugal. In the northwestern Mediterranean, peak spawning occurs in July and August (Hereu et al.
2006, Reñones et al. 2010) and in December in Brazil (Andrade et al. 2003). Aggregation sites also likely
exist in Brazil as spearfishermen have reported large catches (of up to 400 kg) being taken within a few
days from the same areas (Andrade et al. 2003).
This is a monandric protogynous hermaphroditic species, that transitions from female to male with
growth. Females in Tunisian waters reach sexual maturity at age five, and transitioned to males between
nine and sixteen years of age (Chauvet 1988). In the Balearic Islands, females reach sexual maturity at
49 cm total length and six years, and sex reversal can be notably delayed (Reñones et al. 2010). In Brazil,
50% of females reached sexual maturity at 49 cm, the overall largest female was 79 cm and the smallest
male was 80 cm. In Spain, the maximum reported age was 52 years for females and 61 years for males
(Reñones et al. 2007). Based on a longevity of 61 years, age of first maturity of 6.5 years, and applying
the mean generational turnover formula in Depczynski and Bellwood (2006), one generation length is
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estimated to be 33.75 years.
Systems:ÊÊMarine
Use and Trade
This emblematic species is targeted by commercial and recreational fisheries, especially in the
Mediterranean Sea and southeastern Africa. It is also caught by small-scale/artisanal fishers in Brazil,
Mozambique and Madagascar (P. Heemstra unpublished data, S. Fennessy pers. obs. 2013). It is
generally caught using long-lines, hand-lines or spear. This species also supports dive ecotourism
(Briquet-Laugier et al. 2007).
There have been some efforts to develop aquaculture for this species to fill market need left by depleted
wild populations as well as mass production of juveniles to possibly restock wild populations in the
Mediterranean, Portugal and Rio de Janeiro, Brazil (Bruzon 2007, Pierre et al. 2007, Marino et al. 2007,
J.P. Barreiros and A. Bertoncini pers. comm. 2016).
Threats (see Appendix for additional information)
Overexploitation is a major threat to this species. The slow growth rate, protogynous hermaphroditism
and spawning aggregation behaviour of this species causes it to be particularly susceptible to rapid
population decline upon high fishing pressure (Fennessy 1998, 2000).
Conservation Actions (see Appendix for additional information)
Northeastern Atlantic and Mediterranean: A spearfishing ban has been imposed on this species in
France, Monaco, the Azores and Madeira. In France, the first moratorium from 1993 to 1998 prohibited
only spearfishing, but in 2003, it was extended to include angling by both artisanal and professional
fishermen, and is now expected to remain until at least 2023. Increasing abundance in French marine
protected areas (MPAs) is believed to be related to several factors: increased numbers of MPAs and
connectivity between them, spearfishing bans and warming of the Mediterranean Sea (Harmelin 2013).
The removal of legal protections for this species (i.e., a resumption of spearfishing and linefishing)
would impact the re-established juvenile populations that now exist in this area (Bodilis et al. 2003).
Banning spearfishing while allowing linefishing may offer little protection for this and other similar large
grouper species (J.P. Barreiros pers. comm. 2016). At the international level, E. marginatus is listed in
Annex III of the Barcelona Convention (species for which their exploitation is regulated). This species is
also recorded in Annexe III of the Bern Convention, but only for the Mediterranean Sea. A number of
MPAs have also been established which protect both the populations and habitats of this species
throughout various parts of the Mediterranean Sea and Macaronesia (EUNIS 2014). Renones et al.
(2010) recommends implementing a “slot” size limit for this species in Spain to allow only capture of
individuals between 50 and 80 cm total length (i.e., only females) and to establish MPAs with no-take
zones.
Southwestern Atlantic Ocean: In Brazil, there is a minimum catch size of 47 cm for all fisheries that
capture this species, and it occurs in many MPAs. Monitoring of artisanal/recreational fisheries landings
are insufficient in Brazil.
Western Indian Ocean: In South Africa, there is a bag limit of one fish per person per day and a
minimum size limit of 60 cm total length for all fisheries. It occurs in several MPAs in South Africa and
© The IUCN Red List of Threatened Species: Epinephelus marginatus – published in 2018.
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southern Mozambique.
West Africa: There are no species-specific conservation measures in the West African region.
Tidepools are an important habitat for juveniles, and thus, protections within MPA networks are needed
(Barreiros et al. 2004, Afonso et al. 2011). Further genetic research on the populations of this species is
needed (Schunter et al. 2011).
Credits
Assessor(s): Pollard, D.A., Afonso, P., Bertoncini, A.A., Fennessy, S., Francour, P. & Barreiros, J.
Reviewer(s): Linardich, C.
Contributor(s): Padovani-Ferreira, B.
Facilitators(s) and
Compiler(s):
Ralph, G., Craig, M.T.
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Citation
Pollard, D.A., Afonso, P., Bertoncini, A.A., Fennessy, S., Francour, P. & Barreiros, J. 2018. Epinephelus
marginatus. The IUCN Red List of Threatened Species 2018: e.T7859A100467602.
http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
Disclaimer
To make use of this information, please check the Terms of Use.
External Resources
For Supplementary Material, and for Images and External Links to Additional Information, please see the
Red List website.
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http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
13
Appendix
Habitats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Habitat Season Suitability Major
Importance?
9. Marine Neritic -> 9.2. Marine Neritic - Subtidal Rock and Rocky Reefs Resident Suitable Yes
Threats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Threat Timing Scope Severity Impact Score
5. Biological resource use -> 5.4. Fishing & harvesting
aquatic resources -> 5.4.1. Intentional use:
(subsistence/small scale) [harvest]
Ongoing Minority (50%) Slow, significant
declines
Low impact: 5
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]
Ongoing Whole (>90%) Rapid declines High impact: 8
Stresses: 2. Species Stresses -> 2.1. Species mortality
Conservation Actions in Place
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Actions in Place
In-Place Land/Water Protection and Management
Occur in at least one PA: Yes
Conservation Actions Needed
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Actions Needed
1. Land/water protection -> 1.1. Site/area protection
2. Land/water management -> 2.1. Site/area management
3. Species management -> 3.1. Species management -> 3.1.1. Harvest management
5. Law & policy -> 5.1. Legislation -> 5.1.1. International level
5. Law & policy -> 5.1. Legislation -> 5.1.2. National level
Research Needed
© The IUCN Red List of Threatened Species: Epinephelus marginatus – published in 2018.
http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
14
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Research Needed
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.3. Life history & ecology
2. Conservation Planning -> 2.3. Harvest & Trade Management Plan
3. Monitoring -> 3.1. Population trends
Additional Data Fields
Distribution
Lower depth limit (m): 300
Upper depth limit (m): 0
Habitats and Ecology
Generation Length (years): 33.75
© The IUCN Red List of Threatened Species: Epinephelus marginatus – published in 2018.
http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T7859A100467602.en
15
The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2008: T7859A100467602
Scope: Global
Language: English
The IUCN Red List Partnership
The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species
Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership.
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16
... As a consequence of the global decline, the species has been categorized globally as Vulnerable by the International Union for the Conservation of Nature (Pollard et al., 2018) While strong local spawning-site fidelity and lack of spawning migrations in dusky grouper (Lembo et al., 2002) may contribute to population structure, its prolonged pelagic larval phase may contribute to high dispersal and gene flow. Previous population genetic studies of dusky grouper (e.g. ...
... A life-history characterized by slow growth, late maturity, and sequential hermaphroditism makes dusky grouper particularly susceptible to overfishing. The species is the object of highly valuable commercial and sport fisheries that have driven populations into steady decline throughout its range (Condini, García-Charton & Garcia, 2018;Pollard et al., 2018). Dusky grouper is regarded as overexploited in the Mediterranean Sea, presenting concern regarding its protection and sustainable use for Mediterranean countries (Mavruk et al., 2018). ...
Article
• The dusky grouper Epinephelus marginatus is a large epinephelid species that occurs in the eastern and south‐western Atlantic and western Indian Oceans. Late maturity, protogynous hermaphroditism, site fidelity, and overfishing have all contributed to its demographic decline. • Connectivity and demography within a broad sampling of dusky grouper populations throughout its distribution were assessed. To do so, genetic variation at 11 polymorphic microsatellite loci and a partial sequence of the mitochondrial control region (mtCR) were evaluated. • Two major mtCR lineages with a sequence divergence of 1.6% were found. The magnitude of genetic differentiation for mtCR among north and south Atlantic and Indian Ocean populations was high, with ΦST = 0.528. • DEST and results of discriminant analysis of principal component revealed significant microsatellite genetic differentiation between all collection areas. Significant pairwise DEST showed moderate (0.084) to very great (0.603) differentiation. The effective population size was low for all localities, ranging between 25 (Azores Archipelago) and 311 (Rio Grande do Sul). The overall effective population size was estimated as 299 (confidence interval = 215–412), and there was no evidence of strong or recent bottleneck effects. • Local and regional genetic structuring among dusky grouper populations is the consequence of the species' site fidelity, distribution across multiple oceanographic boundaries, and probably also of sequential hermaphroditism that contributes to the intensity of random genetic drift. • The spatial pattern of genetic structuring of dusky groupers is such that fisheries management and conservation of population genetic integrity will have to be pursued at the local and regional scales.
... As highlighted in this current review, there are key aspects of the biology, ecology and fisheries of the dusky grouper that remain poorly understood, such as accurate location of spawning aggregations, and spatial and temporal trends in fisheries landing data, which constitute fundamental information for the planning and implementation of efficient management actions. Despite these crucial gaps in many areas of its geographical distribution, there are fisheries management actions in place for several Epinephelidae species showing promising results (IUCN 2004): (1) A minimum size limit for capture has been implemented for E. albomarginatus in South Africa, where it is prohibited to catch individuals \ 400 mm TL (Fennessy 2004); (2) a limitation in the number of fishing vessels has been used in the Arabian Sea to control fishing effort on E. gabriellae (Macllwain et al. 2008); (3) a total ban has been imposed on the fishing of E. itajara in Brazil, Puerto Rico and the US Virgin Islands (Craig 2011), of E. striatus in the US federal waters and Puerto Rico (Cornish and Eklund 2003), and of E. marginatus in France (Pollard et al. unpublished data); (4) a system of catch quotas has been implemented to control fishing of E. albomarginatus in South Africa (Fennessy 2004), E. striatus in Cuba (Cornish and Eklund 2003) and Hyporthodus niveatus in the USA (Thierry et al. 2008); (5) a fishing ban during specific periods like spawning seasons and spawning aggregations has been implemented for E. striatus in the Dominican Republic, Mexico, the Bahamas and Belize (Cornish and Eklund 2003); (6) the creation of marine protected areas (MPAs) has been broadly used as a conservation tool to protect several endangered Epinephelidae species García-Charton et al. 2008;Wood et al. 2008;Lester et al. 2009;Guidetti et al. 2014;Costello and Ballantine 2015;Di Franco et al. 2016). ...
... As highlighted in this current review, there are key aspects of the biology, ecology and fisheries of the dusky grouper that remain poorly understood, such as accurate location of spawning aggregations, and spatial and temporal trends in fisheries landing data, which constitute fundamental information for the planning and implementation of efficient management actions. Despite these crucial gaps in many areas of its geographical distribution, there are fisheries management actions in place for several Epinephelidae species showing promising results (IUCN 2004): (1) A minimum size limit for capture has been implemented for E. albomarginatus in South Africa, where it is prohibited to catch individuals \ 400 mm TL (Fennessy 2004); (2) a limitation in the number of fishing vessels has been used in the Arabian Sea to control fishing effort on E. gabriellae (Macllwain et al. 2008); (3) a total ban has been imposed on the fishing of E. itajara in Brazil, Puerto Rico and the US Virgin Islands (Craig 2011), of E. striatus in the US federal waters and Puerto Rico (Cornish and Eklund 2003), and of E. marginatus in France (Pollard et al. unpublished data); (4) a system of catch quotas has been implemented to control fishing of E. albomarginatus in South Africa (Fennessy 2004), E. striatus in Cuba (Cornish and Eklund 2003) and Hyporthodus niveatus in the USA (Thierry et al. 2008); (5) a fishing ban during specific periods like spawning seasons and spawning aggregations has been implemented for E. striatus in the Dominican Republic, Mexico, the Bahamas and Belize (Cornish and Eklund 2003); (6) the creation of marine protected areas (MPAs) has been broadly used as a conservation tool to protect several endangered Epinephelidae species García-Charton et al. 2008;Wood et al. 2008;Lester et al. 2009;Guidetti et al. 2014;Costello and Ballantine 2015;Di Franco et al. 2016). ...
Article
Full-text available
The dusky grouper is a large-bodied marine species usually associated with rocky substrates and reefs currently experiencing increasing anthropogenic pressures. Here, we critically evaluate studies conducted during the last few decades on this endangered species, focusing on its biology, ecology, behavior, stock structure and fisheries, and identify future research directions to fill current knowledge gaps. This species plays an important functional role in the rocky bottom habitats in which it lives, usually occupying the highest trophic levels and with the potential role as a keystone species in some ecosystems. It has a complex life cycle characterized by a high longevity, a slow growth rate and a monandric protogynous hermaphroditic mode of reproduction. The species also exhibits spawning aggregation behavior, which makes it more vulnerable to fishing activity. Aside from its ecological importance, this species has high commercial value for professional fishers and is also highly prized by recreational spearfishers. These biological features, associated with increasing fishing pressures throughout most of its geographical distribution, have led to Epinephelus marginatus being included since 2004 in the IUCN Red List of Threatened Species as Endangered. Despite a large amount of research being conducted on this species over the last five decades or so, using a number of different tools and techniques, key questions regarding its biology still remain unanswered. In terms of conservation and management plans designed to safeguard this endangered species, we identified the crucial need to improve fisheries landing statistics for the species and to increase the number of marine protected areas within its distribution beyond the Mediterranean Sea.
... As highlighted in this current review, there are key aspects of the biology, ecology and fisheries of the dusky grouper that remain poorly understood, such as accurate location of spawning aggregations, and spatial and temporal trends in fisheries landing data, which constitute fundamental information for the planning and implementation of efficient management actions. Despite these crucial gaps in many areas of its geographical distribution, there are fisheries management actions in place for several Epinephelidae species showing promising results (IUCN 2004): (1) A minimum size limit for capture has been implemented for E. albomarginatus in South Africa, where it is prohibited to catch individuals \ 400 mm TL (Fennessy 2004); (2) a limitation in the number of fishing vessels has been used in the Arabian Sea to control fishing effort on E. gabriellae (Macllwain et al. 2008); (3) a total ban has been imposed on the fishing of E. itajara in Brazil, Puerto Rico and the US Virgin Islands (Craig 2011), of E. striatus in the US federal waters and Puerto Rico (Cornish and Eklund 2003), and of E. marginatus in France (Pollard et al. unpublished data); (4) a system of catch quotas has been implemented to control fishing of E. albomarginatus in South Africa (Fennessy 2004), E. striatus in Cuba (Cornish and Eklund 2003) and Hyporthodus niveatus in the USA (Thierry et al. 2008); (5) a fishing ban during specific periods like spawning seasons and spawning aggregations has been implemented for E. striatus in the Dominican Republic, Mexico, the Bahamas and Belize (Cornish and Eklund 2003); (6) the creation of marine protected areas (MPAs) has been broadly used as a conservation tool to protect several endangered Epinephelidae species García-Charton et al. 2008;Wood et al. 2008;Lester et al. 2009;Guidetti et al. 2014;Costello and Ballantine 2015;Di Franco et al. 2016). ...
... As highlighted in this current review, there are key aspects of the biology, ecology and fisheries of the dusky grouper that remain poorly understood, such as accurate location of spawning aggregations, and spatial and temporal trends in fisheries landing data, which constitute fundamental information for the planning and implementation of efficient management actions. Despite these crucial gaps in many areas of its geographical distribution, there are fisheries management actions in place for several Epinephelidae species showing promising results (IUCN 2004): (1) A minimum size limit for capture has been implemented for E. albomarginatus in South Africa, where it is prohibited to catch individuals \ 400 mm TL (Fennessy 2004); (2) a limitation in the number of fishing vessels has been used in the Arabian Sea to control fishing effort on E. gabriellae (Macllwain et al. 2008); (3) a total ban has been imposed on the fishing of E. itajara in Brazil, Puerto Rico and the US Virgin Islands (Craig 2011), of E. striatus in the US federal waters and Puerto Rico (Cornish and Eklund 2003), and of E. marginatus in France (Pollard et al. unpublished data); (4) a system of catch quotas has been implemented to control fishing of E. albomarginatus in South Africa (Fennessy 2004), E. striatus in Cuba (Cornish and Eklund 2003) and Hyporthodus niveatus in the USA (Thierry et al. 2008); (5) a fishing ban during specific periods like spawning seasons and spawning aggregations has been implemented for E. striatus in the Dominican Republic, Mexico, the Bahamas and Belize (Cornish and Eklund 2003); (6) the creation of marine protected areas (MPAs) has been broadly used as a conservation tool to protect several endangered Epinephelidae species García-Charton et al. 2008;Wood et al. 2008;Lester et al. 2009;Guidetti et al. 2014;Costello and Ballantine 2015;Di Franco et al. 2016). ...
Conference Paper
A better understanding of population dynamics including the identification of reproductive areas and their contribution to the maintenance of fish stocks is essential for population conservation. Dusky grouper, Epinephelus marginatus, is a broadly distributed fish species, usually found in marine rocky bottoms. It is currently listed as “endangered” by the IUCN Red List. The available information on its population in southern Brazil suggests that the neritic habitat of Carpinteiro Bank - CB is the main growth and spawning ground in the region. We investigated if the dusky groupers caught in the rocky-jetties of Rio Grande city (a littoral artificial habitat with no spawning activity) originated from the CB. We sampled 28 individuals from the littoral rocky-jetties aged between 2 and 12 years, and 44 individuals from the neritic CB aged between 2 and 40 years. Individuals from both areas had their otolith sections analyzed with LA-ICPMS (core-to-edge profiles) for 86Sr:43Ca, 138Ba:43Ca ratios. The otolith core (natal origin) and edge (time shortly before capture) from individuals of the same age class showed no difference between the two sites. Individual profiles of 138Ba:43Ca ratios of fish from the littoral zone indicated, for the first time, that some juveniles of dusky grouper enter the Patos lagoon and remain within the estuarine environment between the first and second years of life. This interpretation of otolith chemical data is supported by the marked differences in salinity between the littoral and estuarine sites in these studies areas, and by the marked differences in otolith 138Ba:43Ca of other fish species analyzed along the salinity gradient in the Patos Lagoon estuary. The identification of differential juvenile habitat use patterns is crucial for the establishment and implementation of management and conservation strategies to safeguard this endangered species.
... PLOS ONE | https://doi.org/10.1371/journal.pone.0226810 December 31,2019 8 / 35 ...
Article
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Marine megafauna has always elicited contrasting feelings. In the past, large marine animals were often depicted as fantastic mythological creatures and dangerous monsters, while also arousing human curiosity. Marine megafauna has been a valuable resource to exploit, leading to the collapse of populations and local extinctions. In addition, some species have been perceived as competitors of fishers for marine resources and were often actively culled. Since the 1970s, there has been a change in the perception and use of megafauna. The growth of marine tourism, increasingly oriented towards the observation of wildlife, has driven a shift from extractive to non-extractive use, supporting the conservation of at least some species of marine megafauna. In this paper, we review and compare the changes in the perception and use of three megafaunal groups, cetaceans, elasmobranchs and groupers, with a special focus on European cultures. We highlight the main drivers and the timing of these changes, compare different taxonomic groups and species, and highlight the implications for management and conservation. One of the main drivers of the shift in perception, shared by all the three groups of megafauna, has been a general increase in curiosity towards wildlife, stimulated inter alia by documentaries (from the early 1970s onwards), and also promoted by easy access to scuba diving. At the same time, environmental campaigns have been developed to raise public awareness regarding marine wildlife, especially cetaceans, a process greatly facilitated by the rise of Internet and the World Wide Web. Currently, all the three groups (cetaceans, elasmobranchs and groupers) may represent valuable resources for ecotourism. Strikingly, the economic value of live specimens may exceed their value for human consumption. A further change in perception involving all the three groups is related to a growing understanding and appreciation of their key ecological role. The shift from extractive to non-extractive use has the potential for promoting species conservation and local economic growth. However, the change in use may not benefit the original stakeholders (e.g. fishers or whalers) and there may therefore be a case for providing compensation for disadvantaged stakeholders. Moreover, it is increasingly clear that even non-extractive use may have a negative impact on marine megafauna, therefore regulations are needed.
... As highlighted in this current review, there are key aspects of the biology, ecology and fisheries of the dusky grouper that remain poorly understood, such as accurate location of spawning aggregations, and spatial and temporal trends in fisheries landing data, which constitute fundamental information for the planning and implementation of efficient management actions. Despite these crucial gaps in many areas of its geographical distribution, there are fisheries manage- ment actions in place for several Epinephelidae species showing promising results (IUCN 2004): (1) A minimum size limit for capture has been imple- mented for E. albomarginatus in South Africa, where it is prohibited to catch individuals \ 400 mm TL (Fennessy 2004); (2) a limitation in the number of fishing vessels has been used in the Arabian Sea to control fishing effort on E. gabriellae ( Macllwain et al. 2008); (3) a total ban has been imposed on the fishing of E. itajara in Brazil, Puerto Rico and the US Virgin Islands (Craig 2011), of E. striatus in the US federal waters and Puerto Rico (Cornish and Eklund 2003), and of E. marginatus in France (Pollard et al. unpub- lished data); (4) a system of catch quotas has been implemented to control fishing of E. albomarginatus in South Africa (Fennessy 2004), E. striatus in Cuba ( Cornish and Eklund 2003) and Hyporthodus niveatus in the USA ( Thierry et al. 2008); (5) a fishing ban during specific periods like spawning seasons and spawning aggregations has been implemented for E. striatus in the Dominican Republic, Mexico, the Bahamas and Belize (Cornish and Eklund 2003); (6) the creation of marine protected areas (MPAs) has been broadly used as a conservation tool to protect several endangered Epinephelidae species García-Charton et al. 2008;Wood et al. 2008;Lester et al. 2009;Guidetti et al. 2014;Costello and Ballantine 2015;Di Franco et al. 2016). ...
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