Al Sawadi – A Weekend Adventure

The Al Sawadi Beach Resort Weekend outing was not the usual ENHG activity. But it seemed a good way to really get the program going. I “discovered” the spot during a one week holiday in mid August and determined that I would offer to organize a weekend trip centred there, with a tour of the Rustaq – Nakhl region as the “natural history” aspect of the trip. I was pleased when twenty people signed up almost immediately – I was overwhelmed when it grew to 50. The Resort staff were really helpful with the reservations. They blocked off twenty-nine rooms, held them for late check-in, gave us a discount on their posted rate and put up with the changes as people discovered they had to work, or had other commitments. Even the Omani Highways Department co-operated! They removed the construction zone that prevented us from making a left turn off the coast highway onto the side road leading to the resort. This was important, as we would have had to drive ten km further down the highway to Barka then do a U-turn and come back ten km to the same place on the other side of the road. And the weekend itself?

Al Sawadi – A Weekend Adventure cont...

Al Sawadi – A Weekend Adventure cont...

The drive from Rustaq to Nakhl is no more than 30 minutes. The fort presents itself as you approach town, just be careful not to turn right immediately after the blue high-way sign, wait for the larger road about 800 feet further

Al Sawadi – A Weekend Adventure cont...

The story began when the decision was made to expand the Abu Dhabi International Airport, constructing a second runway and, eventually, building a new terminal building and related facilities. The organization charged with managing the project, the Special Committee for the Abu Dhabi International Airport, or SCADIA, ordered an environmental impact assessment (EIA) before construction began. The EIA, organized by the international firm URS, determined that there was a large colony of dhub on the site and, given the fact these animals are acknowledged as “protected” by the federal government and are a Class II species recognized by the CITES agreement, the decision was made to capture and relocate as many of these animals as possible.

                            Dhub do not hang around waiting for photographers, so apologies for the string, but…

Initially, the Environmental Research and Wildlife Development Agency (ERWDA, now the Environment Agency, or EA), captured more than a dozen animals and released them on a site west of Abu Dhabi. This pilot project was intended to see how well the animals adapted to capture and relocation.

In the course of the project, it was realized that the species were a relatively newly recognized species (U. lepteni) as opposed to the well-known UAE residents Uromastyx aegyptius microlepis.

Meetings were held in April and early May as the equipment was assembled to begin the rough grading of the site. It appeared there were only a few days available to capture the animals before the bulldozers moved in. As a result, a rescue program was organized and members of the ENHG chapters invited to send volunteers to help capture the dhubs.

For two weekends in May, volunteers set and baited metal live-capture traps and prepared to send captured animals to a temporary shelter in Sharjah. Though almost 30 animals were captured, it was apparent a full-time rescue would have to be organized. Beginning in late May, URS contracted two individuals to conduct the capture. Brien Holmes, of the Al Ain chapter of ENHG, and Thomas Wilems, from Germany, began the process of trapping, identifying and housing dhubs from the site.

Saving the Dhub cont…

There are sections on the archaeology and geology of the UAE’s only mountain (including the recently-discovered, extensive cave system near the summit), as well as studies of its wildlife. The are specific chapters about its flora, mammals, birds, reptiles and invertebrates, each chapter written by experts including many of our own Al Ain ENHG members. The photos are extraordinary, especially those taken by Bob Reimer - no-one should miss his amazing shot of beetles mating. The maps, including a satellite photo, are clear and helpful. The book lacks an index, but that is in hand.

We all hope that books such as this, publicizing the unique habitat of Hafit, might help prevent future developments which intrude on the stark beauty of the mountain.

Wadi Aboul – a Friday Outing

     "For years scientists have assumed that desert varnish was composed primarily of manganese and iron oxides, precipitated out of the rock through weathering processes. However, the varnish structure eluded precise analysis because it is composed of particles too fine to be characterized by X-rays, the main diagnostic tool of mineralogical investigation.
     "Infrared spectroscopy, a technique which illuminates mineral samples with infrared light and records the pattern of absorbed wavelengths, was applied to the study of desert varnish by two Caltech scientists. George R. Rossman, associate professor of mineralogy, and Russel M. Potter, Caltech graduate student, used rock samples from 20 locations in California, New Mexico, and Arizona in the analysis of desert varnish. The samples included quartz, granite, basalt, rhyolite, quartzite, feldspar, and sandstone.
     "The results of the analysis revealed that the main constituent in desert varnish, totaling about 70%, is clay, not manganese and iron oxides. The oxides form the remaining 30%. The red coating on the underside of the varnished rocks, previously believed to be iron oxide, turned out to be 90% clay incorporating an iron oxide stain, similar to the iron in the black finish on the rocks' exposed portions. In addition it was found that all desert varnish, whether it formed on the side of a cliff or on a 10-inch boulder, shares a similar composition."

      HOWEVER: http://www.geo.arizona.edu/palynology/geos462/14rockvarnish.html report differently, namely that desert varnish is:

"a biogenic deposit produced by mixotrophic bacteria living on rock surfaces, digesting organic debris." The paper goes on to explain:
"History of Study: biological origin proposed in 1921. Recent advances based on electron beam microprobe (Hooke et al., 1979), which demonstrated layering of varnish.
"Technique: analyzed by X-ray diffraction (reveals clay mineralogy), infrared spectroscopy, electron microscopy, microprobe, bulk chemical analysis, TAMS dating, isotope analysis."

I conclude that, while the bacteria explanation was first proposed in 1921, it was not widely accepted until only recently, with the Arizona research provided the first (?) evidence to support the theory. Evidently modern

technology provided the means to test the theories.
This discussion evolved when Steve was among the members joining us for the tour of Khudrah. On the gravel plain overlooking the oasis, I explained that the dark stain on the "desert armour", the rocks covering the flat surface of the gravel plain, was believed to be caused by some bacterial action. Steve, to his great credit, undertook to investigate the claim and forwarded links to two papers. One, from Caltech, offered an explanation involving clay while the more-recent Arizona paper supports the bacteria connection.
The Arizona paper also includes some interesting notes explaining the appearance and color of the varnish. As many of you know, the color here is a dark red which suggests, and Arizona confirms, the presence of iron.

"Fluctuations in clays and Fe and Mn oxides and hydroxides produce color:
black: manganese-rich
red: iron-rich"

But it is also interesting that the appearance -- much of our varnish is very shiny or glossy -- varies depending on clay accumulation (the paper makes reference to the ratio of bacteria and clay):

"Rate of bacterial growth relative to clay accumulation produces appearance:
dark dull varnish = bacterial growth dominant
light shiny varnish = clay accumulation dominant "

I trust Steve will let me know if there have been any further developments. And, on behalf of the membership, thank you to Steve for sparking the discussion!

A Friday Outing: The Wadi Kahl to Wadi Sharm Desert Drive

Friday, September 23rd saw 32 people gather outside the Buraimi Hotel for the desert drive from wadi Kahl to Wadi Sharm A distance which could be covered in 20 to 30 minutes by an experienced driver in a hurry, took us about 3 hours. Soft sand is not the same as hard packed sand, dunes are not the same as flats. Long gentle slopes are not the same as short steep pitches – and it is still hot out there. We learned about camels, about their clay rolling areas, about fossils (nice one, Bob) and about the geology of the region (thanks Stephen). We tried out a walkie-talkie system and found it to be an excellent aid – we learned about convoy driving and how easy it is to lose your mates. It was an altogether excellent day. Here are some of the pics people have sent in. Do join us next time.

A Friday Outing: The Wadi Kahl to Wadi Sharm Desert Drive cont…

ENHG members over the years have identified many grave sites and have dated them based on their alignment relative to Mecca – any grave not aligned according to Islamic tradition is pre-Islamic. However, there was a presupposition that the foot to head alignment was the important one, when in fact it is at ninety degrees to this that Islamic tradition follows, because the body is placed in the grave on its side with the face towards Mecca. This addition to our knowledge means we have to go back over all the sites previously identified and re-check their orientation. We learned all this at this grave site along the Kahl – Sharm passage.

                                            Here are some of the places we ENHGers go - Al Ain is in the bottom left corner

of the plants available on the airport site was necessary to ensure the appropriate vegetation would be available at release sites.

Later this year, the rescue operation will move inside the security fencing at the airport to capture dhubs, hares and gazelle.

Although rare and endangered species have been captured and relocated in various programs around the world, it is believed that this is the first instance of reptiles being the subject of such a program.

SCADIA has been so enthusiastic about the rescue program that there are plans to incorporate the dhub population in the final design of the airport, with some of the survivors enjoying a retirement in a special area set aside in preservation for the animals.