A brief overview of the nature

in the United Arab Emirates Dr Christophe Tourenq

Manager, Science and Research, Emirates Wildlife Society-WWF

For most people landing in the UAE, the country appears as a vast hot and arid

hostile desert with buzzing megapoles and a plethora of shopping-malls. But those

who make the extra effort will be rewarded by discovering this is just the surface of a

country with a unique and rich biodiversity.

Habitats

A wide variety of habitats can be found in the UAE, including extensive sand dunes,

sabkhas, coastal mangroves and wetlands, acacia savannah plains, inland gravel

outwash plains and high mountains of the Hajar Range and the Musandam

Peninsula that overlooks the passage through the Arabian Gulf from the Arabian

Sea.

1) Coastal habitats and islands

The Arabian Gulf littoral of the UAE is characterised by a succession of active coastal

sabkhas and mangroves, represented by a single species of tree: Avicennia marina.

Between desert and ocean, sabkhas, transliteration of the Arabic word for a “salt

flat”, develop 300 km in length extending continuously up to 20 km or more inland,

such as the Sabkha Matti, in Abu Dhabi emirate. This expansive area of sabkha, with

a total area of approximately 6,000 km2 extends 130 km southwards from the UAE

coastline into the Kingdom of Saudi Arabia, with the northern and eastern portion

falling inside the boundaries of the United Arab Emirates. Sabkha Matti was declared

of international importance, in terms of its uniqueness and its geological formations.

With the exception of the small site of 6 km2 on the Arabian Sea coast (Khor Kalba;

Sharjah Emirate), the entire natural mangrove is dispersed on the Arabian Gulf coast

where Avicennia marina reaches its northern limit in Asia. The mangrove distribution

is patchy and covers in total about 40 km2 of the UAE shoreline. Most areas of

mangrove are relatively small in size and only a few extensive mangroves exist.

Mangrove patches are known to have been more extensive both historically and in

the recent past prior to human interference.

Compared to the Arabian Sea and Gulf of Oman where the continental shelf drops

quickly below 100m and the salinity does not exceed 37ppt, the Arabian Gulf

coastal waters are extraordinarily shallow (mean depth of 20m), saline (37 to 45 ppt)

and gently shelving with numerous inshore and nearshore islands. Most of these

islands are simply part of a formerly more extensive and continuous sabkha invaded

and dissected by post-Quaternary Shamallic storms and thence inundated by a sea

level rise. Offshore, larger islands are mostly the higher parts of a diapiric surface, the

clearest evidence for which is where the migrating salt has erupted through to the

surface to form distinctive and obtrusive looking hills. Other islands are anything from

tiny, sandy and shelly shoals to those larger with raised coral and outcropping

limestone which are mostly covered with drift deposits.

Coral reefs of the sea are said to be the equivalent of rainforest of the land in terms

of biodiversity and services, they host up to 25% of the world’s total marine wildlife.

More than 50 different species of coral live in UAE. In the Arabian Gulf, corals are at

the northern limit of their geographical distribution in the world. There, they are able

to sustain high salinity but above all, fluctuations in sea-temperatures over 20°C

between summer and winter, which are the highest that any coral reef ecosystem in

the world is reported to be able to withstand!

(http://www.panda.org/who_we_are/wwf_offices/united_arab_emirates/?uProjectI

D=AE0007) Much of this biodiversity is dependent on coral reefs for food, shelter or

breeding, but healthy coral reefs are also an important contributor to the local

economy through tourism, fishing, bio-prospecting and recreational opportunities.

Moreover, coral reefs protect shorelines from waves and strong currents and prevent

erosion. Additionally, coral reefs are considered key to finding new medicines for the

21st century. Many drugs are now being developed from coral reef animals and

plants as possible cures for cancer, arthritis, infections, viruses, and other diseases.

2) Mountains

In the eastern region, the barren mountains form part of the great Hajar Mountain

range which parallels the East coast of the Arabian Sea from the Musandam

Peninsula in the North, to Muscat in Oman in the South. They rise rapidly to 1,300 m

above sea level and then descend to a narrow coastal lowland plain along the Gulf

of Oman. The northern ridges of these mountains, known as the Ru’us al Jibal or

Musandam, face the Strait of Hormuz and are in an enclave of Omani territory. The

highest peak is 2,087m, and the slopes drop precipitously, creating a highly irregular

coastline with spectacular fjord-like valleys. Geologically, the Hajar and Musandam

Mountains are comprised of Palaeozoic, metamorphic and igneous rocks formed at

the site of a mid-oceanic ridge in the Indian Ocean. During the Tertiary and

following uplift, erosion carved out spectacular scenery of rugged mountains,

incised by sharply convoluted wadis. Whereas limestone rocks are abundant in

Musandam, the rest of the Hajar range is showing what geologists from all around

the world come to see: one of the world’s finest and most extensive surface

exposures of rocks of the oceanic crust, with grey-brown ophiolites. The bedrock of

ophiolites is cut by deeply incised wadis which have subsequently been infilled with

fuviatile deposits. Generally, the annual average rainfall in the mountain region and

along the east coast is higher in comparison to the western part of the range.

Wadi Wurayah _ EWS-WWF

The Jebel Hafeet, the unique mountain of Abu Dhabi emirate, in Al Ain, is an isolated

massif 7 km long by 4 km wide culminating at 1,300m above the sea level comprised

of tertiary sedimentary rock (limestone). Because of its isolation from the rest of the

Hajar mountain chain, and its particular geology, Jebel Hafeet is home to a number

of plants which either only occur here or are otherwise very rare in the UAE.

Epipactis veratrifolia_ EWS-WWF

It is also one of the only places in the world where you have the chance to spot the

rare Arabian Tahr (Hemitragus jayakari). This species, like some other rare inhabitants

of the mountains are able to survive thanks to rare permanent water springs, one of

the most spectacular being Wadi Wurayah in Fujairah emirate that was recently

declared as the first mountain protected of the country

http://www.panda.org/who_we_are/wwf_offices/united_arab_emirates/index.cfm?

uProjectID=AE0011).

Cloud on Jebel Hafeet _ EWS-WWF

3) Deserts

Eastwards from the Sabkha Matti, the dominant landform is sand sheet with deflated

gravel plains overlain by aeolian dunes having inter-dunal aeolianite outcrops. The

transition from the flats of Sabkha Matti is gradual with small barchan dunes (=

mobile arc-shaped dunes) forming in the west and transitioning into barchanoid and

transverse dunes in a south easterly direction. The deflated gravel plains which

separate the barchan and barchanoid dune formations are often well vegetated.

Exposed aeolianite (= solidified sediment deposited by the wind) surfaces and

outcrops as well as rocky outcrops occur throughout the landscape. Continuing

further east and south east, as the height above sea level increases, the gravel

plains become smaller, being restricted to small interdunal palaeo surfaces. From

Sila, eastern Abu Dhabi, up to Ajman, south of the sabkah bordering the Arabian

Gulf coast, the dominant sand colour is white-greyish.

Red dunes Empty Quarter_ EWS-WWF

Deeper inland towards the Empty Quarter, a series of transverse (east to west) dunes

of orange-red sand are showing off with, in some cases, extensive interdune plains

(up to 25 km in length). The dunes which separate the plains are referred to as

‘mega barchanoid dunes’ having southward facing slip faces and are relatively

static.

Ghaf forest Ras al Khaimah_ EWS-WWF

The most impressive exemplars of these dunes are found in the Empty Quarter region

near Liwa oasis, south Abu Dhabi. From Ajman to Ras al Khaimah, down to Al Ain in

the south, orange-red sand dunes with extensive ghaf (Prosopis cineraria) forests can

be found as well along the gravel plains bordering the Hajar range

(http://www.panda.org/who_we_are/wwf_offices/united_arab_emirates/?uNewsID

=89720).

Hajar range_ EWS-WWF

Wildlife

The Arabian Peninsula is often regarded as a vast arid land with little or no value

from a biodiversity point of view. However, Arabian ecosystems host unique species

that show remarkable adjustments to survive harsh environmental conditions with

physiological, behavioural and morphological strategies.

Camel Abu Dhabi_ EWS-WWF

On land most animals hide during the day from the heat of the sun either under trees

and bushes or underground. While this is one adaptation to the hot and dry climate,

terrestrial species of the region have over time developed unique features and

become masters at keeping cool, saving water and living within sand and dust.

Examples are the hairy feet of the Sand cat's Cat (Felis margarita) and the hairy paw

pads of the Cheesman's gerbil (Gerbillus cheesmani); or the long fringed toes of the

Arabian toad-headed Agama (Phrynocephalus arabicus), preventing them from

burning and sinking in the hot soft sand; and the physiological ability of the Arabian

Oryx (Oryx leucoryx) to spend weeks without drinking, extracting water from the rare

vegetation.

With Oryx, UAE deserts host another remarkable ungulate, the Sand Gazelle (Gazella

subgutturosa marica), locally known as “Reem”, with which it shares the sparse

vegetation and a unique but more discrete fauna like the Ruppell’s Fox (Vulpes

rupelli), the Cape Hare (Lepus capensis) and the Lesser Jerboa (Jaculus jaculus), the

Sand boa (Eryx jayakari), the Least Semaphore Gecko (Pristurus minimus) and the

Leptien’s Spiny-tailed Lizard (Uromastyx aegyptia. leptieni), known locally as “Dhub”,

the two late species being endemic to UAE and Oman. On the coastal zone, the

desert hosts a rare jewel that may soon be living its last moments on Earth because

of land reclamation for development: the Arabian Wonder Gecko -or Desert Skink

Gecko- (Teratoscincus scincus), a beautifully coloured gecko with a combination of

pink, orange and black spots but as a precious stone, hard to find, because of its

nocturnal lifestyle. This species is only found in the Arabian Peninsula over a small

area between Ghantoot and Umm al Quwayn.

The UAE mountains host two of the most rare and endangered species in the world:

the Arabian Tahr (Hemitragus jayakari) and the Arabian Leopard (Panthera pardus

nimr). The Arabian Tahr is endemic to UAE and Oman arid highlands. Nowadays,

with Jebel Hafeet (Al Ain), Wadi Wurayah in Fujairah emirate is one of only two

places in the UAE where a small population of Arabian Tahr still survives. Its survival is

closely linked with the presence of permanent water holes where it can drink

regularly during the hot season. Mountain habitats are also the playground of other

rare species such as the Mountain Gazelle (Gazella gazella cora), the Blanford’s Fox

(Vulpes cana), the Caracal Lynx (Caracal caracal schmitzi) and Gordon's Wildcat

(Felis silvestris gordoni).

The UAE mountains host two species of amphibians: the Arabian Toad (Bufo

arabicus) and the Dhofar Toad (Bufo dhufarensis) and also five endemic reptiles to

the Hajar range: Blue-tailed Lizard (Omanosaura cyanura), Rock Semaphore Gecko

(Pristurus rupestris), Bar-tailed Semaphore Gecko (Pristurus celerrimus), Banded

ground Gecko (Bunopus spatalurus hajarensis) and Omani Carpet Viper (Echis

omanensis).

Echis omanensis_ EWS-WWF

Under the sea, the marine life of the UAE thrives despite the water reaching almost

30 degree during summer. The Arabian Gulf is rich with coral reefs, fish, plants, turtles,

and mammals.

The number of fish species in Abu Dhabi waters is difficult to precise because it varies

according to multiple parameters (the season, the substrate, salinity, currents, etc.).

Scientists estimate that there are 218 fish species from 71 families from cartilaginous

(= sharks and rays) to bony fishes in UAE waters only. Among these fish are several

species that only occur in the Arabian Gulf such as the Arabian Gulf sailfish

(Istiophorus platypterus) and reef fish like the Persian Dottyback (Pseudochromis

persicus), the Dark Butterflyfish (Chaetodon nigropunctatus) and the Arabian

Butterflyfish (Chaetodon melapterus). At least 46 different species of sharks, guitarfish

and rays are present in the waters of the Arabian Gulf and Eastern Coast of UAE,

including the majestuous Whale Shark (Rhincodon typus).

There are a lot more to reef fish than the colourful fish we see in aquariums around

the world. Several commercially important fish are primarily linked to the coral reef

habitat, such as the grouper species (Serranidae) or “Hamour” as we know them in

the UAE. The Orange-spotted Grouper (Epinephelus coioides) used to be a very

common reef species in the Arabian Gulf, where it is the most important

commercially exploited species, representing up to 35% of the catch and 40% of its

value in Abu Dhabi Emirate.

Of the seven species of marine turtles worldwide, two species, the Hawksbill turtle

(Eretmochelys imbricata) and the Green turtle (Chelonia mydas), are predominantly

occurring in the Gulf waters. Both species use intensively the area at Eastern Qatar-

western Abu Dhabi Emirate for foraging and nesting on the sandy beaches of the

coast and on the islands. They are considered as endangered by the International

Union for Conservation of Nature (IUCN).

The good old tales of Mermaids might well have been Dugongs (Dugong dugong)

playing tricks with sailors. Dugong derives from the Tagalog term “dugong” which

was in turn adopted from the Malay “duyung”, both meaning "lady of the sea".

Dugongs, also called ‘sea cows’, because they graze on sea grasses are mammals

and unlike some whales and dolphins, they cannot hold their breath under water

more than a few minutes at a time. The UAE holds the largest known population of

Dugongs outside Australia. Latest surveys conducted in Abu Dhabi indicate a

population of approximately 2,500 Dugongs. The species is fully protected by

Federal and local laws and the only main threats are loss of habitats, pollution,

drifting nets and boat collision. This population depends on the seagrass beds for

their feeding and on islands and coral reefs of the western Abu Dhabi Emirate.

Most people’s favourite sea-mammals, dolphin and whales are part of the rich

marine life of the UAE. It might come as a surprise to many that the UAE hosts at

least 17 different species of whales and dolphins, even the mighty Blue whale

(Balaenoptera musculus) has been seen here. The deep underwater canyons and

cliffs on the edge of the continental shelf off UAE's east coast is where most species

can be found, but the contrast of the warm, sandy shallows of the Arabian Gulf are

favored by some species adapted for shallow water life, such as the Indo-Pacific

humpback dolphin (Sousa chinensis) and the rare finless porpoise (Neophocaena

phocaenoides). Some species are at home in both environments for example the

famous “Flipper”, the Bottlenose Dolphin (Tursiops) of which two species might occur

(T. truncatus and T. aduncus) in the region. The diverse and productive seas of the

west and east coasts provide suitable habitat for many more cetaceans than

previously expected to occur.

And a lot has still to be discovered. During the last decade, two new species of

mammals, 3 species of reptiles, one species of freshwater fish

(http://www.panda.org/who_we_are/wwf_offices/united_arab_emirates/?165821/N

ew-species-of-Arabian-freshwater-fish-found-in-Oman) , 164 species and 6

subspecies of terrestrial arthropods, and ten species of corals, new for science have

been described in UAE and Oman, and numerous species of marine invertebrates

still remain unnamed. However, this fragile and unique biodiversity pays a toll to the

unplanned coastal development, mining, overgrazing, uncontrolled hunting,

overfishing, freshwater overexploitation, and climate change.