Eretmochelys imbricata - UAE National Red List of Herpetofauna: Amphibians & Terrestrial Reptiles, Sea Snakes & Marine Turtles
Publication
Asessment status in full
Vulnerable
Assessment status abreviation
VU
Assessment status criteria
B2ab(i,ii,iii,iv); D1
Assessment rationale/justification
This species is found throughout the territorial waters of the United Arab Emirates, although feeding areas are concentrated in the central and western areas of the Arabian Gulf, with very few found in eastern parts of the Arabian Gulf and along the Gulf of Oman. The species nests within the Arabian Gulf, and in the UAE nesting is primarily occurs on off-shore islands, although nesting also currently occurs on the mainland coast at Jebel Ali. A single recent occurrence at Khor Kalba on the east coast is excluded from the assessment until repeated annual nesting occurs. Some historical nesting sites, both on the islands and on the mainland, are no longer used. The extent of occurrence (EOO), based on known active nesting sites within the UAE exceeds 30,000 km<sup>2</sup>. The area of occupancy (AOO), based on the known nesting sites, is restricted, estimated at very much less than 500 km<sup>2</sup> using a 2 x 2 km grid (IUCN 2017). The species occurs in ten locations (with those within Marawah Marine Biosphere Reserve and the Al Yasat MPA considered a single location in each case), again based on the currently known nesting sites.With the currently available information, the species is assessed as Vulnerable (VU B2ab(i,ii,iii,iv); D1) on the basis of the restricted AOO and number of locations, with an observed continuing decline in the quality and extent of habitat, especially of nesting beaches, and an inferred continuing decline in the number of locations, with some sites not experiencing regular nesting activity (e.g., Al Siniyah) and others at risk (e.g., Jebel Ali). The species also qualifies as VU under criterion D1 given that there are estimated to be fewer than 1,000 mature individuals.Although natal homing imprecision means that some individuals originating outside the UAE may nest within the UAE, the potential rescue effect is not considered significant, and there is no regional adjustment to the assigned category.The ongoing conservation actions and research for this species within the UAE need to be maintained and expanded. In particular, monitoring and research are essential to the understanding of long-term future population trends, and actions are needed to protect nesting sites, especially those not currently within protected areas. This species should be reassessed for the UAE National Red List if new data become available on population size or trend, or on the impact of the known threats.Even though most currently-utilised nesting habitat for Hawksbill turtles is currently under some level of protection, we cannot assume that nesting and feeding habitats within Protected Areas are not at risk, as different activities with the potential to impact on the quality of these habitats may still take place within or near the boundaries of these areas. Therefore, monitoring and implementation of management plans should be exercised and assessed to infer the potential level of impact and risks to Hawksbill turtle populations, and to assess the efficacy of both management plans and protected area management for this species.The evidence of fine-scale population structure within the UAE and between the UAE and other nesting colonies in the Arabian Gulf provided by the study of Natoli et al. (2017) is relevant, even though based on a small sample size, as it provides an overall picture of the metapopulation dynamic for hawksbill turtles, where restricted gene flow between northern and southern areas of the Gulf, and between the inshore and offshore nesting colonies in the UAE, particularly Sir Bu Nair and Dubai nesting areas, exist. From these findings, one could infer that the known threats may have differential effects across subpopulations, and impacts may be particularly significant on those with a reduced number of nesters, as is the case of Dubai (the Jebel Ali nesting colony), with implications for the entire UAE subpopulation. As a result, future assessments would have to assess this impact carefully, and the species might well qualify for the Endangered category on the basis of actual or future declines in the numbers of mature individuals.
Assessment year
2018
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 specifics
IUCN v3.1 + Regional Guidelines v4.0
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.
Endemic to region
Not assigned
Endemism Notes
Is an endemic?: Not_assigned
Threats listed in assessment
In the Arabian region, the impact of human activities remains largely unchecked and present the primary threat to Hawksbill turtles in UAE waters. The following threats have been described, with boat strike, fishing gear entanglement, marine debris ingestion, and nesting habitat destruction resulting from rapid coastal development representing the primary threats. Destruction of nesting habitat Coastlines in the UAE have undergone very rapid urban, industrial and tourism development, which has led to the destruction of nesting habitat, especially on the mainland. some island nesting sites have been less impacted, for example, those occurring within the Marawah Biosphere Reserve. Because Hawksbills prefer to nest under vegetation they are particularly impacted by beach-front development and the clearance of dune vegetation. Gas and oil refineries may seriously disrupt nesting habitat.Nesting habitat destruction has been rapid and extensive in the UAE, and has not yet ceased. For example, the Jebel Ali nesting site is likely to be severely impacted or lost if the development of Palm Jebel Ali recommences. Fisheries bycatch Hawksbills are particularly susceptible to entanglement in gill nets and capture on fishing hooks (Mortimer 1998). The full extent of the impact of fisheries bycatch on Hawksbill turtle populations is not yet well understood in the UAE. It is considered that increasing numbers of adults are stranding with evidence of drowning in fishing gear (Pilcher et al. 2008). Recent assessments in the Gulf region raise concerns about the potentially high impact that fisheries bycatch may have on turtles (83.6% of bycatch composition, representing ~4,726 captures year (Abdulqader et al. 2017). Boat strike, entanglement and ingestion of marine debris Ingestion of marine debris by Hawksbills is significant (White 2004). Recent research found that the majority of turtle strandings (including Hawksbill) in Abu Dhabi showed evidence of human interaction (boat strike 20% and entanglement 58%) (EAD 2016). Oil pollution There is evidence oil pollution has a greater impact on Hawksbills than on other species of turtle (Meylan and Redlow 2006). In some parts of the world (especially the Middle East) oil pollution is a major problem. Natural threats relevant to the UAE Hawksbill turtles are also subject to a range of natural threats. The Arabian Gulf undergoes extreme water and air temperature fluctuations, which present climate-related challenges to species diversity and distribution. Many smaller turtles strand in the Arabian Gulf from cold-stunning in the winter months (Pilcher et al. 2014b, 2015). Shell, egg and meat trade and consumption Despite listing of all Hawksbill populations on Appendix I of CITES since 1977, trade continued at high levels, with Japan continuing to import shell under a CITES reservation (exception) until 1993. Illegal trade continues, but there is no information on how this trade impacts the populations found in UAE waters. Intense levels of egg exploitation continue in many parts of the world., and adult and juvenile Hawksbills are still killed for meat in many areas, and in some areas turtle meat is used by fishermen as shark bait (J. Mortimer and C. Lagueux unpubl. data 2008). Again, there is no evidence of consumption in the UAE at present. Destruction of foraging habitat Hawksbills are typically associated with coral reefs, which are among the world's most endangered marine ecosystems. Climate change has led to massive coral bleaching events with permanent consequences for local habitats.In the Arabian Gulf, corals exist in a naturally extreme environment (Sheppard et al. 1992) at the absolute limit of their environmental tolerances (Riegl et al. 2011). Sea surface temperatures can fluctuate by more than >20'°C over the course of a single year, with summer daily-mean temperatures of >35'°C, while winter winds can chill water to <12'°C (Sheppard et al. 1992, 2010). Corals in the Arabian Gulf also survive in a hypersaline environment year round with salinities regularly >42 ppt (Sheppard et al. 1992) with significant seasonal insolation fluctuations (Sheppard et al. 2010). Partly as a result of these conditions, marine macrobenthos in the Arabian Gulf is limited in diversity and distribution (Basson et al. 1977, Al-Yamani et al. 2009). Corals in the Arabian Gulf are not only subject to natural stressors, but are also subject to increasing pressure from anthropogenic impacts such as overfishing, large-scale coastal development (Sheppard et al. 2010, Sale et al. 2011) and bleaching events as a result of human-induced climate change (Riegl et al. 2011).Coral reefs in the Arabian Gulf were severely affected by thermal bleaching in both 1996 and 1998 (Riegl 2002), and to a lesser extent in 2002 and 2010 (Foster et al. 2012), causing extensive loss of coral cover from patch reefs located along the coastline in the UAE (Riegl 1999, Sheppard and Loughland 2002). A shift in dominance towards faviids and poritids was also noted as well as spatial variation of coral communities with some areas showing low species richness (Burt et al. 2011). The loss of acroporid dominated communities and the shift to poritid and faviid dominated communities was reported by Bauman et al. (2012) to have occurred more widely than previously thought.The knock-on effect on other reef-dependent organisms is largely unknown, although Buchanan et al. (2015) identified 23 coral-dependent fishes of the Arabian Gulf and determined that, due to the limited area and degraded and fragmented nature of coral assemblages in the Arabian Gulf, all coral-dependent fishes were at elevated risk of extinction as defined by the IUCN Red List of Threatened Species' Categories and Criteria. Hybridisation and population constraints At certain sites where Hawksbill numbers are particularly low, they regularly hybridise with other species of sea turtles.A recent study (Natoli et al. 2017) raised concerns over the genetic viability of the UAE - and the wider Arabian Gulf - population of this species. The study found UAE individuals to have low genetic variability, with differences between populations both within the Arabian Gulf and between the Gulf and Indian Ocean populations, and that the Gulf population overall experienced a bottleneck/founder event. Predation Nest disturbance and the predation of eggs and young turtles by native and non-native (e.g., domestic dogs) is an unquantified threat but may be significant at some sites. For example, the single known nesting attempt on the east coast of the UAE was predated by an Arabian red fox (Hebbelmann et al. 2016).
Conservation Measures
Conservation measures:
Conservation measures notes:
Required conservation measures: