Carcharhinus falciformis | UAE National Red List of Marine Species: Reef-building corals, cartilaginous fishes and select bony fishes

Taxa
Carcharhinus falciformis | (Bibron, 1839)
Location
Countries in Assessment
United Arab Emirates
Country ISO code(s)
ARE
Does the assessment cover a marine EEZ area(s)?
Off
Scope (Assessment)
National
Taxon
Taxonomic Group
Vertebrates
Taxonomic Group Level 2
Fishes
Assessed taxon level
Species
Taxon distribution as listed in assessment
The Silky Shark occurs throughout UAE waters. Elsewhere, it is circumglobally distributed in tropical waters (Last and Stevens 2009).
Habitats and Ecology
Ecological system type
Terrestrial system
No
Freshwater system
No
Marine system
Yes
Habitat
Habitat details as listed in assessment
The Silky Shark is a circumtropical oceanic and coastal-pelagic species, most often found near the edge of continental and insular shelves at depths of 200 m or more in the epipelagic zone. It is often associated with islands, insular slopes and deepwater reefs preferring warmer waters (about 23'°C) although it also occurs from the surface to a depth of at least 500 m offshore (Last and Stevens 2009). Smaller sharks are often found in coastal nurseries and adults further offshore over deeper water. In pelagic habitats, the Silky Shark is often associated with drifting materials on the surface (Filmalter et al. 2013). Life history parameters of this species vary considerably among regions (Clarke et al. 2015a). The maximum size varies from 229-371 cm total length (TL) with a size at maturity from 180-230 cm TL for males and 180-246 cm TL for females (Clarke et al. 2015). Age at maturity ranges from 5-13 years for males and 6-15 years for females with maximum ages of 8-28.6 years for males and 11-35.8 years for females. The Silky Shark gives birth to live young, averaging 5-7 pups per litter with a range of 2-18 pups per litter (Clarke et al. 2015a). Size at birth ranges from 65-81 cm TL and the gestation period ranges from 9-12 months depending on location and study (Clarke et al. 2015). Anderson and Ahmed (1993) report juveniles of 56-63 cm TL captured off the Maldives. Fecundity increases with increasing size of females, and females give birth every 1-2 years (Clarke et al. 2015). In the eastern Arabian Sea, total length and age at maturity for males is 201-“223 cm (TL) and 10 years, and 224-“231 cm and 11 years for females (Varghese et al. 2016). Generation length is estimated to be 15 years based on the average age of maturity of females as 9 years old and average maximum age of 21 years old (excluding outliers). This is in close agreement with generation length of 16 years in Dulvy et al. (2008).
Is there a map available in assessment?
Yes
Assessed status
Asessment status in full
Near Threatened
Assessment status abreviation
NT
Assessment status criteria
A2cd
Assessment rationale/justification
The Silky Shark occurs throughout UAE inshore and offshore waters. Little specific data are available for this species in the UAE. There has been a total ban on fishing for this species in UAE waters since 2019. This species is valued for its meat and fins across the Arabian Sea region. It is one of the dominant species in landings across the Arabian Sea region, and both adults and juveniles are landed. 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 pelagic tuna longline and purse seine 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 20-30% over the past three generation lengths, or about 45 years. It is listed as Near Threatened and nearly meets the thresholds for Vulnerable A2cd.
About the assessment
Assessment year
2019
Assessors/contributors/reviewers listed
UAE National Red List Workshop
Affliation of assessor(s)/contributors/reviewers listed on assessment
Government
IGO
Assessor affiliation specific
Government|IGO
Criteria system
Criteria system specifics
IUCN v3.1
Criteria system used
IUCN
Criteria Citation
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.
Endemism
Endemic to region
Not_assigned
Endemism Notes
Is an endemic?: Not_assigned
Conservation
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 Arabian Gulf are experiencing high levels of disturbance and quickly deteriorating due to major impacts from development activities (including dredging and reclamation), desalination plants, industrial activities, habitat destruction through the removal of shallow productive areas and major shipping lanes (Sheppard et al. 2010).
Conservation Measures

Conservation measures:
Conservation measures notes:
Required conservation measures:

Scientific Name Kingdom Phylum Class Order Family Genus
Carcharhinus falciformis Animalia Chordata Chondrichthyes Carcharhiniformes Carcharhinidae Carcharhinus