Taxon name
Carcharhinus altimus
(Springer, 1950)
Uploaded by
National Red List Database
Taxonomic information
Scientific name
Carcharhinus altimus
(Springer, 1950)
Assessed taxon level
Species
Higher level taxonomic groupings
Vertebrates
Fishes
Species authority
(Springer, 1950)
Taxonomic notes and synonyms listed
The Bignose Shark is morphologically distinct but genetically similar to the Sandbar Shark (Carcharhinus plumbeus) (Naylor et al. 2012, Duffy and Struthers 2017).
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
In UAE waters, the Bignose Shark occurs only in the Sea of Oman in deep waters. Little specific data are available for this species in the UAE. It is apparently highly migratory, and has slow life history characteristics including low fecundity and a low annual rate of population increase. Considering this, the species has a low capacity to recover from even moderate levels of exploitation. It is especially susceptible to exploitation (target and bycatch) in many largely unregulated longline fisheries that operate within its range outside and surrounding UAE waters. Some management measures are now in place in the Arabian Sea region (i.e. through the IOTC), 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. This species faces intense fishing pressures throughout the Arabian Sea. Based on recorded levels of exploitation and decline in habitat quality, it is suspected to have declined by at least 30% over the past three generation lengths, or about 64 years. It is listed as Vulnerable 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
In the UAE, the Bignose Shark occurs only on the Sea of Oman coast. It is excluded from the Arabian Gulf. Globally, it is widespread but patchy throughout the Indo-Pacific and Atlantic Oceans (Last and Stevens 2009). This species is possibly easily confused with Carcharhinus plumbeus (Henderson et al. 2016).
Is there a map available in assessment?
Yes
Habitat and systems
Ecological system type
Habitat
Habitat details as listed in assessment
The Bignose Shark occurs mainly on the edge of continental shelves in waters to 800 m deep, but is more common between 80 and 220 m with occasional captures in shallow water (Tester 1969). Individuals have been caught at night near the surface over deep water in the Maldives (Anderson and Ahmed 1993) and this species is thought to display diurnal vertical migrations (Anderson and Stevens 1996). It attains a maximum size of 282 cm total length (TL) with an average reproductive age of ~21 years (Compagno 1984, Kohler et al. 1995, Jensen et al. 1996). Males reach maturity at 216 cm TL and females at 226 cm TL. Females are reported to give birth to 1-13 pups per litter with size at birth around 70-90 cm TL.
Threats and conservation measures listed
Threats listed in assessment
Information pertaining to threats specific to the UAE are unavailable. This species is impacted by target (for fins and their valuable meat) and bycatch fisheries that are active elsewhere in its range. 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).
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.
