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

Taxa
Rhina ancylostoma | Bloch & Schneider, 1801
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 Bowmouth Guitarfish occurs throughout UAE waters (Tourenq et al. 2008). Globally, it is widespread in the Indo-West Pacific (Last et al. 2016).
Habitats and Ecology
Ecological system type
Terrestrial system
No
Freshwater system
No
Marine system
Yes
Habitat
Habitat details as listed in assessment
The Bowmouth Guitarfish has an intertidal and coastal distribution. It generally occurs close inshore and around coral reefs to about 90 m (Fricke et al. 2011). It occurs on or close to the seabed, mainly over sandy or muddy substrates. Very little is known about the life history characteristics of this species. However, it is a large species growing to at least 294 cm total length (TL) and is lecithotrophic viviparous (Compagno and Last 1999, Jabado 2018). Males mature between 150 and 175 cm TL, and one pregnant female was recorded with 9 mid-term embryos ranging between 27-31 cm TL (Last and Stevens 2009). A single new born individual of 53 cm TL has been recorded from Bahrain (Randall 1995). Further research on the biology and life history of this species is needed.Maximum age for Rhynchobatus spp. in Australia is 5 years (males) and 12 years (females), but these data were not from the largest individuals (White et al. 2014) and are not reliable for the estimation of generation length for rhinids. This is therefore estimated from the maximum age (19 years) and age at maturity (7 years) taken from the growth curve provided by White et al. (2014) for the Giant Guitarfish (Glaucostegus typus), which gives an estimated generation length of 13 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 Bowmouth Guitarfish occurs throughout UAE inshore waters. This species is not targeted in the UAE and trawling has been banned there since 1980; however, it is frequently taken as bycatch in coastal net fisheries. It is taken in variable quantities in gill net and trawl fisheries elsewhere in the Arabian Gulf, and coastal habitat degradation is a significant threat, particularly in the Gulf. It is under extremely intense and increasing demersal fishing pressure in much of the Arabian Sea region. It exhibits 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 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 30-50% over the past three generation lengths, or about 39 years. It is listed as 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
This species is impacted by fishing activities in the UAE, where it is targeted for local consumption and taken as bycatch (Jabado 2018). This species may also be 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-family: Georgia; font-size: 12pt;""> 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:
Conservation measures notes:
Required conservation measures:

Scientific Name Kingdom Phylum Class Order Family Genus
Rhina ancylostoma Animalia Chordata Chondrichthyes Rhinopristiformes Rhinidae Rhina