Taxon name
Carcharhinus plumbeus
(Nardo, 1827)
Uploaded by
National Red List Database
Taxonomic information
Scientific name
Carcharhinus plumbeus
(Nardo, 1827)
Assessed taxon level
Species
Higher level taxonomic groupings
Vertebrates
Fishes
Species authority
(Nardo, 1827)
Location and scope
Specific locality or subnational name or regional name
United Arab Emirates (the)
Scope (of the Assessment)
National
Countries included within the scope of the assessment
United Arab Emirates (the)
Does the assessment cover a marine EEZ area(s)?
Not_assigned
Conservation Status
Qualifying criteria (if given)
A2cd
Criteria system used
IUCN
(see Assessment details)
Assessment rationale/justification
The Sandbar Shark occurs throughout UAE inshore and offshore waters. It is caught with longlines, hook-and-line, and set bottom nets and the fins are generally considered to be of high value. While there is limited information available on this species in the region, its large size, valuable fins and intensive fisheries mean that, like many other large carcharhinids in the region, it has declined significantly. In addition, this is one of the least biologically productive sharks, with high intrinsic vulnerability, and information from other parts of its global range have demonstrated that it is quickly overfished even with moderate levels of fishing. Little specific data are available for this species in the UAE. It is especially susceptible to exploitation (target and bycatch) in many largely unregulated gill net, longline and trawl fisheries that operate within its range outside and surrounding UAE waters. Some management measures are now in place in the Arabian Sea region, although domestic fisheries are likely to continue. Though data specifically from the UAE are not available, individuals in the UAE are a component of a larger, interconnected and migratory population that occurs broadly in the north-western Indian Ocean. It is inferred that declines reported in the Arabian Sea region are representative of its status in the UAE. Based on recorded levels of exploitation and decline in habitat quality, it is suspected to have declined by at least 50% over the past three generation lengths, or about 86 years. It is listed as Endangered A2cd.
Assessment details
Assessors/contributors/reviewers listed
UAE National Red List Workshop
Criteria system used
IUCN
Reference for methods given
IUCN. 2012. IUCN Red List Categories and Criteria: Version 3.1, Second edition. IUCN, Gland, Switzerland and Cambridge, UK. iv + 32pp pp. And IUCN. 2012. Guidelines for Application of IUCN Red List Criteria at Regional and National Levels: Version 4.0. Gland, Switzerland and Cambridge, UK: IUCN. iii + 41pp.
Further information
Endemism (according to assessment)
Endemic to region
Not assigned
Taxon distribution as listed in assessment
The Sandbar Shark occurs throughout UAE waters. Elsewhere, it is broad ranging but patchily distributed (Last and Stevens 2009).
Is there a map available in assessment?
Yes
Habitat and systems
Ecological system type
Habitat
Habitat details as listed in assessment
The Sandbar Shark occurs in coastal, often shallow waters and is associated with sandy or muddy flats, bays, estuaries and harbours (Grubbs et al. 2007). The species also occurs further offshore, particularly on banks, near islands, flat reefs and other topographic features in open waters from the surface to 280 m depth, but is typically found in waters less than 100 m depth (Compagno et al. 2005). It attains a maximum size of at least 240 cm total length (TL) (Ebert et al. 2013). Size at maturity in females ranges from 129-158 cm TL and from 123-156 cm TL in males. This species is viviparous with a yolk sac placenta with a gestation period estimated at 9-12 months (McAuley et al. 2007). Females apparently have young only every two or three years. Litter size is variable and depends in part on the size of the mother, and ranges from 1-10 (Tester 1969, McAuley et al. 2007). Size at birth varies slightly by region but does not follow the same geographic pattern. New born pups range from 40-65 cm TL (Capapé 1984, McAuley et al. 2007).Sandbar Sharks are slow-growing K-selected species (Hoff and Musick 1987, Sminkey and Musick 1995). Wild populations grow very slowly and mature at a relatively late age (Lawler 1976, Casey et al. 1985, Sminkey and Musick 1995). Maturity in these studies was estimated at 13-16 years. The ages at which 50% of female and male sharks were mature was estimated to be 16.2 and 13.8 years, respectively (McAuley et al. 2006) and longevity is 35-41 years (McAuley et al. 2006). In the Tasman Sea, age at maturity for females and males was 9.5 and 7 years, respectively (Geraghty et al. 2015). Generation length is therefore estimated as 28.5 years.
Threats and conservation measures listed
Threats listed in assessment
In the UAE, sharks have been impacted by targeted commercial fisheries until 2014 when a ban on export of sharks was imposed (Ministry of Climate Change and Environment). Sharks continue to be impacted by artisanal and bycatch fisheries (Annual Fisheries Statistical Report for Abu Dhabi Emirate 2001-2018), though catch data are not species-specific. Studies show that sandbar sharks are a long-lived species with low fecundity and are very susceptible to overfishing (Springer 1960, Casey et al. 1985, Sminkey and Musick 1995, 1996; McAuley et al. 2005, 2006). Marine habitats in the region have experienced high levels of disturbance and are quickly deteriorating due to major impacts from development activities (Sheppard et al. 2010). Corals in the UAE and Arabian Gulf have severely declined due to the increasing frequency of mass bleaching events caused by rising water temperatures, which is a consequence of climate change, as well as pervasive coastal development (Riegl et al. 2018, Burt et al. 2019).
Publication
Ralph, G.M., Stump, E., Linardich, C., Bullock, R.W., Carpenter, K.E., Allen D.J., Hilton-Taylor, C., Al Mheiri, R., and Alshamsi, O. 2021. UAE National Red List of Marine Species: Reef-building corals, cartilaginous fishes and select bony fishes. 2021. Ministry of Climate Change and Environment, Dubai, United Arab Emirates.