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

Taxa
Pristis zijsron | Bleeker, 1851
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
Taxonomic Notes
Recent taxonomic work has confirmed that the Green Sawfish (Pristis zijsron) is a valid species with an Indo-West Pacific distribution (Faria et al. 2013).
Taxon distribution as listed in assessment
The Green Sawfish occurs throughout UAE waters. Globally, it was historically widespread in the Indo-West Pacific, including throughout the Arabian Sea region from the Red Sea to India (Harrison and Dulvy 2014, Dulvy et al. 2016). Its current occurrence in much of this region is uncertain due to a lack of reliable data, but it is presumed to have been extirpated from much of its range due to severe impacts from intensive inshore gill net and trawl fisheries. It is currently known to be extant in Sudan, Eritrea and the UAE (Dulvy et al. 2016, Jabado et al. 2017).
Habitats and Ecology
Ecological system type
Terrestrial system
No
Freshwater system
No
Marine system
Yes
Habitat
Habitat details as listed in assessment
Green Sawfish are most common in shallow water coastal and estuarine areas, but occur to depths to over 70 m (Stevens et al. 2005). In the UAE, specimens of up to 600 cm TL were reported from shallow sandy areas with seagrass or further offshore by fishers (Jabado et al. 2017). A 350 cm total length (TL) female and a 250 cm TL male tracked in Australia remained in shallow water (mean depth &lt;1.5 m) and within 200 m of a mangrove shoreline (Peverell and Pillans 2004, Stevens et al. 2008). The young are known to use nearshore and estuarine areas as nurseries, and adults occur more broadly and into deeper areas (Stephenson and Chidlow 2003).Green Sawfish may be the largest of the sawfishes, with reports of individuals up to 730 cm TL (Weigmann 2016). Mean size at birth in the Gulf of Carpentaria is 76 cm TL, and size at maturity at 340 to 380 cm TL (Peverell 2008, Last and Stevens 2009). Age and growth based on specimens from the Gulf of Carpentaria indicate that maturity is reached at about nine years, and maximum age may be &gt;50 years (Peverell 2008). Little is known of its reproductive biology. Reproduction is aplacental viviparous and litter size is about 12. Demographic models based on life history data from the Gulf of Carpentaria indicate that the generation time is 14.6 years, the intrinsic rate of population increase is very low (0.02 yr<sup>-1</sup>), and population doubling time is ~28 years (Moreno Iturria 2012).
Is there a map available in assessment?
Yes
Assessed status
Asessment status in full
Critically Endangered
Assessment status abreviation
CR
Assessment status criteria
A2bcd
Assessment rationale/justification
The Green Sawfish occurs throughout UAE inshore and offshore waters, and was historically relatively abundant there. Capture of this species has been banned in the UAE since 2008, but accidental captures, especially in gill net fisheries, still occur. According to fisher interviews conducted in the UAE, sightings of this species declined by 72% over at least the past 17 years and that it was historically more abundant around 20 years ago. The species is now very rarely sighted, with the last sighting occurring in Abu Dhabi in 2016. 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 demersal 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. 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 fisher interviews, recorded levels of exploitation and decline in habitat quality, it is suspected to have declined by at least 80% over the past three generation lengths, or about 45 years. It is listed as Critically Endangered A2bcd. Based on the continuation of gill net fisheries and nearshore habitat degradation, the species remains under threat, though the ban of its capture in the UAE may have mitigated threats to some degree. Further research is needed on population trends and life history.
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
In the UAE, this species has been impacted by high levels of largely unmanaged and unreported mortality in target and bycatch fisheries. Fishers reported overfishing as the major cause for the observed decline in this species (Jabado et al. 2017). Though fishing for this species in the UAE has been banned since 2008, the species remains greatly threatened by accidental capture. Other threats include habitat loss (particularly loss of mangrove forest, intertidal areas, and coastal development), pollution, and climate change. Marine habitats in the Gulf, including the UAE, are experiencing high levels of disturbance 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). Suspected historical nurseries sites used by this species have been lost to coastal development (Al Hameli pers. comm. 2019). Across its range, continuing threats from mostly unregulated and unmanaged fisheries as well as habitat loss and degradation are resulting in the continual declines of remnant populations (Dulvy et al. 2016).
Conservation Measures

Conservation measures:
Conservation measures notes:
Required conservation measures:

Scientific Name Kingdom Phylum Class Order Family Genus
Pristis zijsron Animalia Chordata Chondrichthyes Rhinopristiformes Pristidae Pristis