Chelonia mydas | UAE National Red List of Herpetofauna: Amphibians & Terrestrial Reptiles, Sea Snakes & Marine Turtles

Taxa
Chelonia mydas | (Linnaeus, 1758)
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
Reptiles
Assessed taxon level
Species
Taxon distribution as listed in assessment
Green turtles are by far the most abundant species of turtle in the Arabian region and the population there makes up a substantial percentage of the global population, with large populations located in Oman and Yemen (Ross and Barwani 1982, Nasher and Jumaily 2015). The species occurs throughout UAE waters in the Arabian Gulf and the Sea of Oman (<a href=""http://seamap.env.duke.edu/"" style="""">OBIS-SEAMAP</a>; Halpin et al. 2009). In the UAE, foraging aggregations are reported in waters off Abu Dhabi (EAD 2016), Ras Al Khaimah (Al-Ghais et al. 1998), Umm Al Quwain (Emirates Nature-WWF), and feed in large aggregations in the Alqurm protected area in Khor Kalba on the Gulf of Oman coast (EPAA Sharjah internal reports). Linkages between foraging areas in UAE and nesting sites in Oman have been demonstrated through a tracking project of Emirates Nature. One female has been tracked from the eastern coast of UAE to the Bay of Bengal (near the Andaman and Nicobar Islands (Robinson et al. 2017).Green turtles nest in the Arabian Gulf in the waters of Saudi Arabia, Kuwait, and Iran in limited numbers with the exception of Bahrain and Qatar (Pilcher et al. 2015), with extensive nesting occurring on beaches in Oman and Yemen. In the UAE, there are historical references from fishers and local communities to nesting sites in several places along the UAE coast, including on Sir Bu Na'air Island (Sharjah), and in 2010 Al Suweidi et al. (2012) reported infrequent nesting on the island, then in 2014 a single nest was found on the east coast at Khor Kalba in the Alqurm protected area (Hebbelmann et al. 2016), two years after this site was designated as a protected area and thirty years after last recording nesting. The local community at Khor Kalba had reported up to 50 nesting females using the beach each season, however, nesting had declined and then ceased in the 1980s (Hebbelmann et al. 2016).In Abu Dhabi, there are no significant wide and long sandy beaches of the kind of habitat found elsewhere in the region where animals nest, and it is likely that historically there were no extensive nesting sites on the Arabian Gulf coast of the UAE, however, the extent of previous nesting occurrence in the UAE prior to intensive development is uncertain.The Green turtle has a circumglobal distribution, occurring throughout tropical and, to a lesser extent, subtropical waters (Atlantic Ocean -“ eastern central, northeast, northwest, southeast, southwest, western central; Indian Ocean -“ eastern, western; Mediterranean Sea; Pacific Ocean -“ eastern central, northwest, southwest, western central). Green turtles are highly migratory and they undertake complex movements and migrations through geographically disparate habitats. Nesting occurs in more than 80 countries worldwide (Hirth 1997). Their movements within the marine environment are less understood but it is believed that green turtles inhabit coastal waters of over 140 countries (Groombridge and Luxmoore 1989).
Habitats and Ecology
Ecological system type
Terrestrial system
No
Freshwater system
No
Marine system
No
Habitat
Habitat details as listed in assessment
Within the UAE, the main foraging areas are associated with seagrass beds along the Arabian Gulf coast from Ras Al Khaimah to Abu Dhabi. On the east coast, the species is likely to forage on algae, cephalopods, small fishes, seagrass etc (F. Yagmour pers. comm. 2018). The EPAA Sharjah is in the process of concluding a study on the diet component of green turtles from the Gulf of Oman. There has been extensive coastal habitat change within the UAE, however, the scale of impacts on turtle habitats is less well known. It is assumed that foraging habitat, especially seagrass beds have declined, but there are no precise estimates of the scale of decline. AGEDI (2013) found seagrass beds in the Arabian Gulf as a whole to be poorly represented in protected areas and considered the seagrass ecosystem to be Endangered, however extensive areas of seagrass occur in UAE waters. Within Abu Dhabi Emirate, seagrass beds are a protected critical habitat and represented within several marine protected areas (Al Dhaheri et al. 2017). Despite this, a continuing decline in habitat quality and extent is inferred based on a range of threats, including coastal development and pollution, oil spills, dredging and so on.The seagrass meadows of the Arabian Gulf are poorly studied (Campbell et al. 2015). The most extensive seagrass meadows in the Arabian Gulf are found along the coast of Abu Dhabi Emirate, while seagrass can also be found in other Emirates; such as Al Taweelah and Jebel Ali (Erftemeijer and Shuail 2012), as well as Khor al Beidah in Umm al Qawain, and Ras Al Khaimah (Emirates Nature -“ WWF in press). The waters of the Arabian Gulf are subject to large variations in salinity and temperature (Price and Coles 1992), and these conditions contribute to the presence of the opportunistic, short-lived seagrass species in the UAE that recover quickly and rapidly recolonize open substrate. The large variations in sea surface temperature result in stress that places limits on survival and colonization (Price and Coles 1992). The presence of only three species of seagrass (Halophila ovalis, Halodule uninervis, Halophila stipulacea) in the Gulf might be related to these environmental conditions (Campbell et al. 2015). Like most sea turtles, this species is highly migratory and use a wide range of broadly separated localities and habitats during their lifetimes. Upon leaving the nesting beach, hatchlings begin an oceanic phase, perhaps floating passively in major current systems (gyres) that serve as open-ocean developmental grounds. After a number of years in the oceanic zone, these turtles recruit to neritic developmental areas rich in seagrass and/or marine algae where they forage and grow until maturity. Upon attaining sexual maturity, turtles commence breeding migrations between foraging grounds and nesting areas that are undertaken every few years. Migrations are carried out by both males and females and may traverse oceanic zones, often spanning thousands of kilometres. During non-breeding periods adults reside at coastal neritic feeding areas that sometimes coincide with juvenile developmental habitats.The generation length of the turtles found in UAE waters is estimated at 42.8 years (see <a href=""http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T4615A11037468.en"">Table 3, Supplementary material, Seminoff 2004</a>).
Is there a map available in assessment?
Yes
Assessed status
Asessment status in full
Vulnerable
Assessment status abreviation
VU
Assessment status criteria
C1
Assessment rationale/justification
Green turtles occur throughout UAE territorial waters as passage animals (from the primary nesting sites in Oman and Yemen) to the Arabian Gulf and in foraging habitats. Extensive nesting used to occur, on the east coast at least, however, this declined and then ceased with the commencement of extensive coastal development, however, there have been recent reports from both the Gulf of Oman coast and the Arabian Gulf coast of nesting attempts by Green turtles.Extrapolating from population surveys undertaken in protected areas in Abu Dhabi coastal waters, it is suspected that the overall number of mature individuals occurring within UAE territorial waters is likely to be less than 10,000. Whilst the current population trend is not known, a future continuing decline in the number of mature individuals is inferred from the three primary threats; ingestion of marine debris, boat strikes, entanglement (in marine debris, including abandoned and lost fishing gear), and habitat loss from a range of drivers. The scale of this population decline is uncertain, but it is reasonable to suspect a decline of at least 10% in the number of mature individuals over a 100-year time frame (one generation length = 42.8 years). As a result, the Green turtle is assessed as Vulnerable (VU C1). Whilst nesting attempts have recommenced in UAE waters, this contribution to the population is at present not significant, and the Green turtle is considered a non-breeding visitor for this national assessment. The condition of the North West Indian Ocean population is considered to still be deteriorating, and so there is no change in the category for this national assessment. Populations outside the UAE are impacted by light pollution at nesting sites in Oman (resulting in declines in recruitment), whilst the impact of other threats such as bioaccumulation of heavy metals, the long-term impacts of oil pollution, mortality of hatchlings in beach debris, and increased storm and other climatic change, require ongoing research.
About the assessment
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
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.
Endemism
Endemic to region
Not_assigned
Endemism Notes
Is an endemic?: Not_assigned
Conservation
Threats listed in assessment
Sheppard et al. (2010) reported on the unprecedented changes to Arabian Gulf marine and coastal habitats over the past decade, which has seen rapid industrial development, large-scale land reclamation, coastal infrastructure, tourism and housing development, and long-term fisheries activities, all of which have caused widespread loss and degradation of benthic habitats. Seagrass habitats in the Arabian Gulf have suffered as a consequence though there are no published reports on the scale of these impacts or the extent and rates of decline (Erftemeijer and Shuail, 2012). The species faces a range of significant threats in UAE waters; Boat strikes In Abu Dhabi, it was found that 20% of all stranded turtles died from vessel strikes. EPAA Sharjah is in the process of concluding a three-year study on the impact of boat strikes on marine turtles, including this species (EAD 2016). Boat strike occurrence on the eastern coast of Sharjah is also frequent. Fisheries bycatch The full extent of impact on green turtle populations is not yet well understood in the UAE, but 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).On the east coast, fishers report that turtles are often caught, but that they are released alive. Entanglement and ingestion of marine debris The understanding of the level of impact of marine debris and entanglement on marine turtle is limited for the region, but recent findings of marine debris ingestion by green turtles indicate a potentially high level of interaction between these turtles and marine debris along the Gulf of Oman coast of the UAE (Yaghmour et al. 2018a,b).In Abu Dhabi, 52% of marine turtle mortalities were attributed to entanglement in abandoned fishing gear. A recent EPAA study found that sea turtles may also be caught in abandoned gargoor fish traps (EAD 2016, Yaghmour et al. 2018b). Coastal development Green turtles are typically associated with seagrass beds that grow in shallow waters and therefore are affected by coastal development. Turtles have been found within water intakes of desalination plants but it is not known if this species is impacted by this threat. Natural threats relevant to the UAE Green turtles are also subject to 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 (Robinson et al. 2017), although these threats may not be so significant to this species. At the global scale, the species may be impacted by a range of threats, however, the impact of these threats on animals found in UAE waters is not known. Pollution and pathogens Marine pollution and debris that affect marine turtles (i.e. through ingestion or entanglement, disorientation caused by artificial lights), as well as impacts of pervasive pathogens (e.g. Fibropapilloma virus causing Fibropapillomatosis) on turtle health, although there are no records at present of this virus in UAE waters.The EPAA Sharjah is in the process of concluding a three-year study on the impact of oil spills on marine turtles which include this species. Marine debris (plastics, ropes, is a significant threat to this species. A study from the east coast found 86% of dead individuals found contained marine debris. Climate change Current and future impacts from climate change on marine turtles and their habitats (e.g. increasing sand temperatures on nesting beaches affecting hatchling sex ratios, sea level rise, storm frequency and intensity affecting nesting habitats, etc.). A primary turtle foraging habitat, seagrass beds, is known to be sensitive to increasing temperatures (Arias-Ortiz et al. 2018).
Conservation Measures

Conservation measures:
Conservation measures notes:
Required conservation measures:

Scientific Name Kingdom Phylum Class Order Family Genus
Chelonia mydas Animalia Chordata Reptilia Testudines Cheloniidae Chelonia