Newsletter September 1999 No. 190

Newsletter September 1999 No. 190

Contents

• Discovering treasures in our archives, a Lost City and more
• Keeping in touch via the email discussion group at listbot.com
• Understanding and appreciating the ancient desert around us
• Our roots: ‘Bish’ Brown, founder of the Emirates Natural History Group

“In a bookshop in Stirling, Scotland, I obtained a second-hand copy of a book called ‘The Sand Kings of Oman’ by O'Shea published in 1947. It describes his experiences while based at Sharjah Fort during his career as an RAF officer in 1944. Chapter 17 describes an incident when a colleague flies off course and sights ruins of a town in the Empty Quarter -- Rubh al Khali, and how O'Shea proceeds on an expedition to locate it.”

So begins an article by John D. MacRae which appeared in the March 1980 issue of the Bulletin published by the Abu Dhabi chapter of the ENHG. Those who share my own enthusiasm for the desert can imagine how excited I was to discover this article which was, like the lost city, waiting to be rediscovered.

When the committee decided last spring to see if we could manage our archive material more productively for members, I don’t think any of us imagined what we would find. We had already thrown out a lot of old notes and miscellany. Then, in August, I began reading a collection of bound papers.

The Bulletins were published by the Abu Dhabi group between 1976 and 1990, with three issues each year. There are approximately 300 articles by ordinary members, some of the leading amateur natural historians of the time, as well as archaeologists involved in uncovering the secrets of Hili, Umm an Nar, Wadi Kubh and Qarn bint Saud. There are discussions of bird sightings, fish observed, along with bees and wasps and snakes and lizards. A wealth of information!

The committee members knew there were articles of interest to members in past Newsletters, including the work of food specialist Phil Iddison and Al Ain’s ‘reluctant lepidopterist’ Michael Gillet. Work was already underway to collect and organize these works to redistribute to members.

While the committee considers how to make the material available, the task of making the articles available electronically has already begun. Volunteers are already busy entering the information in MSWord format. The texts will then be converted to HTML format and, if all goes well, posted on a public web site for everyone to enjoy.

In the meantime, a list of bulletin articles is available and individual members may request copies of articles. As we have only one set of the Bulletins, we are reluctant to release them for general circulation.

“At four o'clock in the afternoon, after a hard gallop across the sands, we reached the slopes of the hill, which was about 500 feet above sand level. The summit, which I estimated was 1000 yards long, was as flat as a billiard table and the crumbling sandstone cliffs were precipitous and slippery. The camels were left grazing on some harm bushes at the foot of the hill while Schultz, Hamid and I climbed the rock, reaching the summit after a stiff climb. It was not quite as flat on top as we had imagined. The sides were smooth and covered with a layer of sand, but in the center there was a large bowl-shaped depression with gently-sloping sides. The slopes were profuse with vegetation, including stunted gharf and samr bushes, and a short, dry grass with razor-like edges. What took our breath away, however, was the sight of a derelict town at the base of this bowl.

‘”The buildings covered about two acres and were surrounded by a low wall of crumbled sandstone blocks which at one time had been much higher. Most of the buildings were a mass of rubble, so that it was difficult to distinguish houses or streets, but two of the towers were still standing; these measured 30 feet in circumference and 40 feet high. The tops were not crenellated like the fort towers of Oman, but smooth and unembellished, with small lookouts through which one had a good view of the surrounding desert. The walls themselves were in places four feet thick, the stone blocks -- the largest of which measured two feet in length and 18 inches in width -- being held together by a rough mortar made of gypsum and clay.”

Does such a city really exist? Thesiger, Thomas, Lawrence and others mentioned such a place. Bedouin legends talk about such a place.

A perfect article for those among us who still doubt our natural history is exciting and magical!

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Last year, the Al Ain Chapter of the Emirates Natural History Group established an email discussion group at listbot.com. This is a free service for individual members.

What is an email discussion group? It is an easy way for individuals to keep in touch with one another. An email message sent to one address is ‘broadcast’ to all subscribers. With an increasing number of our members maintaining email accounts, it seemed appropriate to use one of the free services available on the internet so that members can keep each other informed.

How do I susbscribe? Last year, all members who noted an email address on their membership application form were sent an invitation to subscribe to the group. Those who wanted to take advantage of the service simply sent a blank reply to the listbot.com server to complete the registration; it is that easy. Anyone with access to the Internet can be a subscriber to the discussion group. To subscribe on your own:

• go to the ENHG web page at http://enhg.listbot.com
• click on the button for new subscriber
• follow the instructions and fill in information as requested (leave any spaces blank, if you prefer)

As memberships are processed, the committee will check that all members who indicate an email address are on the distribution list for the discussion group. Those who are not listed will be sent a private invitation; if you do not wish to receive messages, simply ignore the invitation; the ENHG cannot add your address without your permission.

How can I use the discussion group? Since its inception, few individuals have bothered to use the service to contact other members of the Al Ain chapter. It is hoped that, as individuals become more familiar with the service, they will use the system to ask questions, invite others to join them for impromptu outings, as well as pass on news and information to other members.

For example, if you would like to know where to find a den of desert foxes within a half hour’s drive of Al Ain, send an email addressed to enhg@listbot.com. It is very likely someone in our group will have some information for you. Or information on ideal swimming sites in the nearby mountains of Oman, or where to find Dhubs, or the most likely spot to observe owls, find Stone Age arrowheads, or the starting point for the climb to the Hanging Gardens.

The most regular contributor to the group at the moment is The Twitchers’ Guide contributed by Peter Hellyer and Simon Aspinall. Each month, they report bird sightings recorded by other ENHG members. For the many bird watching enthusiasts in our group, this is a useful guide to current activities in the bird populations resident in or just passing through the UAE.

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Most of the surface of the present day UAE is a sand desert, stretching from the Arabian Gulf coast south to the unbroken and uninhabited sands of the Empty Quarter, and east to the gravel plains bordering the Hajar Mountains. The desert is a geologically recent feature, the result of prolonged subaerial erosion and deposition in an arid environment. The sands overlie the thick, oil-rich sedimentary strata of the Arabian Platform which constitutes the bedrock of most of the UAE, but the oil producing rocks are nowhere exposed at the surface, and are known only from drilling.

In many areas near the coast, the sand is stabilized by vegetation, although the natural flora has been altered in recent times by extensive grazing of domesticated animals. Further inland the sands may be quite barren, as few plants can successfully colonize the mobile dunes.

Sand dune formation is controlled by a combination of wind strength and direction, and sediment supply. In detail, however, the formation of dune patterns is complex and remains poorly understood. Within a given area the dune pattern may be quite regular, but also very intricate. Physical features are typically created on several different scales: giant sand ridges on a scale of hundreds of metres to a few kilometres, sand dunes measured in metres to tens of metres, and ripples on a scale of centimetres to a metre or more. This hierarchy can be readily observed in the deserts of the UAE.

Since dune patterns vary with wind direction, seasonal or occasional variations in wind direction introduce new elements into the overall pattern. These elements may reinforce or cancel each other, in the same manner as ocean waves. In addition, because sand dunes cannot move or change as quickly as ocean waves, past history may play a significant part in what we see today. Despite relatively consistent prevailing wind directions in the present day UAE, dune patterns and alignment vary considerably from area to area.

The largest dune features of the present day UAE, including the major transverse dunes of Liwa and Manadir, the smaller eroded dune ridges of the Northern Emirates, and the longitudinal dunes of the south-west, are believed to date from the most recent glacial period, more than 10,000 years ago. A glacial origin for these major features is consistent with the fact that they do not seem to be aligned with today's prevailing winds.

The present day wind regime appears to be transporting material from the coast inland and reworking the surface of the major earlier structures without, so far, removing or reorienting them. For example, one may observe between Abu Dhabi and the Liwa oasis that extensive tongues of pale sand resembling a choppy sea of dunes (aligned NE-SW) are filling in broad troughs between higher, flatter ridges of red sand (aligned WNW-ESE). The latter are known as suruq , or easy travel zones, and are interpreted as the eroded cores of older, larger ridges. Further inland, however, the major transverse dune ridges of Liwa and Manadir are neither in motion nor are they being eroded at the present time, although the smaller dunes on their surfaces conform to present day winds.

In addition to changes in wind regime, the UAE deserts have experienced changes in rainfall at various times in the past. This is indicated by the widespread occurrence of outcrops of lightly cemented, cross-bedded dune sands. These were cemented by the precipitation of calcium carbonate and other salts from ground water at a time when the water table was higher than it is today. Other evidence of higher rainfall in the past includes playa lake sediments, horizons containing abundant fossil roots and burrows, fossil reeds, crocodile bone, freshwater mollusc shells and trails, and fragments of ostrich eggshell. Occasional gravel deposits, often preserved as low, flat-topped hills or mesas , testify to the presence of rivers.

Some of these features may be attributable to the alternation of so-called pluvial (wet) and inter-pluvial (dry) periods recognized elsewhere and believed to correlate with the stages of Pleistocene glaciation. Arid conditions in the UAE predated the Pleistocene, however. The widespread Miocene deposits of the Baynunah Formation (c.6-7 million years old) in the west of Abu Dhabi are interpreted as a major river system that watered a semi-arid, subtropical savannah. The Baynunah formation contains the fossilized remains of early relatives of elephants, hippopotamus, horses, cows, crocodiles, turtles and other animals. The intervening Pliocene is not known from the UAE, but was a period of drought in both East Africa and the Mediterranean.

Sabkha is the Arabic term for low-lying saline flats subject to periodic inundation. Three types are recognized, based on their environment of formation. All are found in the UAE. Coastal sabkha, as the name implies, forms at or near the marine shoreline. Fluvio-lacustrine (ie river-lake) sabkha is formed in association with riverine drainage patterns in arid areas. Inland or interdune sabkha is found in low-lying basins within the sand desert.

All sabkhas share certain characteristics. Although they are restricted to hot, arid regions, the sabkha surface is always very close to the local water table, usually within about a metre. Groundwater is drawn towards the surface by capillary action and evaporates in the upper subsurface in response to the high temperatures. There it deposits dissolved salts, including calcium carbonate, gypsum (CaSO4-2H2O), anhydrite (CaSO4) and sodium chloride or halite (NaCl), which precipitate in that order. These salts create a hard, impermeable crust in a zone about half a metre below the surface. This crust, along with high salinity, discourages all plant growth. The crust also impedes the drainage of surface water, so that after rains the sabkhas flood. The surface water then evaporates over time, often leaving behind a dazzling white crust of salt.

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(The July/August 1995 issue of the Newsletter contained the sad news of the death of 'The Father of Local Natural History', J.N.B. [Bish] Brown.)

J.N.B. "Bish" Brown, formerly of ADMA-OPCO, and founder of the Emmirates Natural History Group, died peacefully in hospital in England on August 3 after a long illness. He was 69.

He, his former employers and many friends in Abu Dhabi would all agree happily that, while Bish had, with quiet efficiency, carried out his tasks at ADMA-OPCO dutifully, he will be remembered mainly for his great contributions, stretching over 40 years, to the promotion of the study of the natural history of the Arabian Gulf.

Bish Brown was fortunate to be just young enough to escape service in the second world war, though only for a matter of weeks. Indeed, he had already completed flying training for the British Royal Navy's Fleet Air Arm when the war ended, and remained proud of his fighter pilot training for the rest of his life.

He first came to the Gulf in 1951, to work in Kuwait, for what was to become the Kuwait Oil Company. An interest in the world outside oil, however, soon developed and Bish was one of the founders of the Ahmadi Natural History Group, the first such body established anywhere in the region.

Bish spent 20 years in Kuwait, amassing a wealth of information about the country's bird, animal and plant life and helping to lay the groundwork for subsequent studies of its natural history. A couple of years in the vastly different environment of Japan followed, but by 1976, he had returned to the Gulf, taking up a job in Sharjah.

Transferred to Abu Dhabi the next year, he and his wife Beth went home on leave, bought an old Land Rover, and proceeded to drive to Abu Dhabi in August 1977, all without the benefit of air conditioning.

Once back in the Emirates, he was a prime mover along with current British Ambassador Anthony Harris and an ADMA colleague, Rob Western, in the establishment of the Emirates Natural History Group, and settled down to nearly 50 years work on promoting the study of the UAE's environment.

Although he retired from ADMA-OPCO in 1985, he was back a couple of years later to work for the Centre for Documentation and Research in Abu Dhabi's Old Fort on classifying and expanding the ENHG's collections, and stayed until nearly 1992 before finally retiring from the Gulf.

The contribution made by Bish Brown to the study of natural history of the Emirates was unparalled. In this modern age of specialist studies, he was remarkable in the breadth of his interests and the depths of his self-taught knowledge. There was no one better with whom to go on a field trip. He could identify grasses and plants, spot birds, catch small mammals, tell companions the names of lizards and snakes, identify the tracks of small insects, and round out the process with an impromptu lecture about the origin of a piece of pottery -- in short, a latter day Renaissance Man, harking back to a time when breadth of knowledge and interest was valued more highly than specialization in more and more tightly defined spheres of study.

Bish's great love, though, was reptiles, not just lizards, but snakes of all kinds. He could catch them, photograph them from close range without showing any fear of their venom, and produced the first, and so far the only, check list of UAE snakes. This pasttime, or absorbing passion, had, of course, its odd aspects. With the amused tolerance of his wife, a large dustbin outside his front door was ocassionally used as a receptacle where oil company friends would deposit live snakes caught in the desert for him to study.

Quiet and unassuming, Bish had, at the same time, an enormous ability to communicate his enthusiasm for natural history to others, and to teach them to understand and to love the varied delights of the UAE environment.

Sadly, his illness over the past couple of years prevented him from preparing for publication his vast collection of notes and photographs from four decades of studying the Gulf's natural history. (Editor’s Note:The Newsletter will reprint a number of articles from the ENHG Bulletins including articles contributed by ‘Bish’ Brown. I had the personal good fortune to have met Bish in 1989 and he shared with me a rough map of sites where camel caravans had routinely stopped as they traveled between Al Ain and Abu Dhabi. His infectious curiosity and enthusiasm, coupled with his wealth of knowledge, made him a most interesting individual! It is hoped that Rob Western, one of Bish’s constant companions, will speak to our group later this season.)

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