Stegostoma tigrinum - UAE National Red List of Marine Species: Reef-building corals, cartilaginous fishes and select bony fishes
Location
Countries in Assessment
United Arab Emirates (the)
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
Taxonomic Notes
The nomenclatural history of the species is somewhat complicated. The name Stegostoma fasciatum (Hermann, 1783) has been the standard name used, however Dahl et al. (2019) concluded that the original name Stegostoma tigrinum Forster, 1781 is the correct senior synonym.
Taxon distribution as listed in assessment
The Zebra Shark occurs throughout UAE waters (Field 2005). Globally, it is found in inshore waters of the continental and insular shelves of the Indo-West Pacific (Compagno 2001).
Habitats and Ecology
Ecological system type
Habitat
Habitat details as listed in assessment
The Zebra Shark occurs in tropical and subtropical, shallow inshore and offshore waters, often found on and around coral and rocky reefs and on sandy plateaus near reefs, at depths down to at least 62 m. It is often observed resting on the bottom as well as swimming near the surface as both juveniles and adults. The species undergoes seasonal movement patterns, forms aggregations and demonstrates strong site fidelity to particular reefs (Dudgeon et al. 2013), which may make them more susceptible to targeted fishing.The Zebra Shark is an oviparous species. Size at birth ranges between 20 and 36 cm total length (TL). Reproductive periodicity in the wild is unknown. Captive aquaria animals have demonstrated annual egg laying periods of up to 3 months with 40-80 eggs laid per year (Robinson et al. 2011) with up to 25% of eggs resulting in hatchlings (L. Squire Jnr pers. comm. 22/07/2014). Age of maturity of captive female sharks is approximately 6-8 years of age based on the commencement of egg laying (Thomas pers. comm. 18/02/2015, Robinson pers. comm. 11/01/2015) and 7 years of age for males (Watson pers. comm. 18/02/2015). Adults reach a maximum size of 246 cm TL with no sexual dimorphism evident (Dudgeon et al. 2008) and live over 28 years in aquaria (Thomas pers. comm. 17/02/2015). Generation length estimates based on 6 years first age at maturity and 28 years maximum longevity for female sharks is 17 years.
Is there a map available in assessment?
Yes
Assessed status
Asessment status in full
Vulnerable
Assessment status abreviation
VU
Assessment status criteria
A2cd
Assessment rationale/justification
The Zebra Shark occurs throughout UAE coastal waters usually near coral and rocky reef habitat, and is relatively common there. It is susceptible to capture in a range of inshore fisheries, but is rare in landings in the UAE due to its relatively low value. This species is not targeted or valued in markets of the UAE, trawling has been banned there since 1980 and it remains commonly sighted by divers. It has strong site fidelity and can form aggregations, which can facilitate the rapid removal of individuals in fisheries operations. In the Arabian Sea, it is landed in India and Pakistan, but less commonly elsewhere. It is especially susceptible to exploitation (target and bycatch) in many largely unregulated gill net 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 30% over the past three generation lengths, or about 50 years. It is listed as Vulnerable A2cd.
About the assessment
Assessors/contributors/reviewers listed
UAE National Red List Workshop
Affliation of assessor(s)/contributors/reviewers listed on assessment
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
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). This species may also being impacted by habitat degradation due to coastal development, especially nursery grounds. Marine habitats in the 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.<em style=""font-size: 12pt; font-family: Georgia;""> 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).
Conservation Measures
Conservation measures:
