Contents:
Blue-tailed lizard drinking water
Backyard Terrarium
"Springtime" in Oman
Land Snails in Fox Droppings
Hajar Mountain Nature Hike
Clam shrimps found at Hatta, too
New Site for Rare Pond Snail
Shelling Report October/November 2000
Tahr on Jebel Hafit
Facts about Bats
Caralluma in Flower
Blue-tailed lizard drinking water
(Reptiles)
By Dr Reza Khan
We were out in Wadi Wurayyah earlier this year. We drove our 4WD vehicle up
to the end of the wadi bottom track, past the waterfall. It was 9 in the morning
when we started looking for signs of animals and noting the plant cover of the
area around. Almost the entire vegetation cover of the area was dry barring a
few Tephrosia, Gymnocarpus and Euphorbia larica. Reed and grass species grew
along the wadi where there was water around. Dyerophytum indicum leaves had a
full layer of wax and when we removed it the leaf appeared brittle.
Most of the wadi was dry except for the portions where the wadi had run deep
through a very narrow gorge that is unapproachable from the topside of the wadi.
At the end of the track there was a fairly big pool still receiving little water
from a feebly flowing stream. There were several toads but no tadpoles and many
wadi fish Garra barreimiae. There was also a swarm of whirligig beetles, diving
beetles, dragonflies and larvae of both beetles and dragonflies. Many snails had
accumulated on a mat of algae, partly submerged in the pool.
Close to the pool several pieces of small rocks remained misplaced due to the
activities of humans or vehicular movements. Water seeped close to such stones.
We saw a Blue-tailed lizard (Lacerta cyanura), a species endemic to the Hajar
Mountains, walking by the side of the pool. It came close to one of the upturned
stones, slowly went at its side where there was just a bit of water and seemed
to sip! At this time I could go within a metre of the lizard. After a minute or
so the lizard started moving away from the stone and literally ran from there to
the steep side of the wadi and disappeared completely.
When we first saw the lizard we thought it was looking for insects. But this is
not its usual haunt for searching food, as it prefers dry rocky areas. We
followed it for over 10 minutes when it covered more than 5 metres before
reaching the particular stone that had little water at its base.
The place from where it drank(!) water was shadowed. So, I could not be
absolutely sure that it was sipping water. But the position I got in my picture
reveals it was doing something that could be similar to drinking water. Also,
the way it vanished from the site indicated that it did not come to the side of
the pool looking for food. This may seem unremarkable, but it is common for arid
region reptiles to satisfy all or most of their fluid needs from their food,
without actually drinking. For example, there are no reported observations of
mountain agamas or geckos drinking water.
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Backyard Terrarium
(Reptiles)
By Gary Feulner
Fascinated by an epidemic of amphisbaenids (legless lizards) in a neighbour's
yard after recent rains, Christine Namour searched her own backyard and turned
up not only an amphisbaenid, but also thread snakes (Leptotyphlops spp., true
reptiles that look like spaghetti).
Under rocks, she found the small but very successful little snail Allopeas
gracilis, which can also be found in grass and on the base of mossy trees. The
shell of A. gracilis is a tall thin spiral typically from 0.5 to 1.0 cm long,
and the aperture is U-shaped without any lip. Alive, the shell usually appears
two-tone -- yellow in front and brown at the tip. The animal itself is pale
yellow. A. gracilis is believed to be a native of the New World tropics but is
now a cosmopolitan resident of the tropics and subtropics worldwide, due to
dispersal by man and agriculture. It requires moisture, however, and is not
found in the wild in the UAE.
Christine's garden pond, which filled up after recent rains, now sports a
small population of dragonfly larvae, and adult dragonflies congregate in view
of the back porch. She plans to keep the pond topped up and landscaped so she
and the children can continue to watch the action, which has included good
examples of mating, egg-laying and territorial behaviour.
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"Springtime" in Oman
(Insects) (Natural History)
Report by Gary Feulner
National Day weekend saw Gary Feulner and Geoff Cosson hiking to the top of
the Saiq Plateau (2400m) in the eastern Jebel Akhdar, overlooking the Ghubrah
Bowl (Wadi Mistal) between Nakhl and Rustaq. This area supports permanent
springs where the relatively porous carbonate rocks of the plateau overlie
impermeable older rocks. It also had healthy autumn rains this year.
This was reflected in a weekend count of 13 species of butterflies, including
a Yellow Pansy and abundant Giant Skippers and Desert Orange Tips, both species
rarely seen in the UAE.
The steep, north-facing slopes inside the bowl, where they are not vertical
cliffs, support a veritable forest of trees such as wild olive or 'utm (Olea cf.
europaea), nimt (Sageretia spiciflora), boot (Monotheca buxifolia) and others.
They benefit, presumably, not only from subsurface water but also from the shade
of the escarpment.
On top of the plateau the vegetation is much sparser but the views are grand
for 360 degrees, one can see north to the coast and west all the way to the
radar dome atop Jebel Shams. One floral constant at higher elevations was the
bright yellow flowering Euryops pinifolius, a tall woody member of the daisy
family.
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Land Snails in Fox Droppings
(Mammals)
Report by Gary Feulner
Examining the contents of one of a number of samples of Blanford's fox
droppings he'd collected from various mountain sites around the UAE, Peter
Cunningham was surprised to find no fewer than 8 small (5mm) land snail shells
of three different species. Peter had never encountered this phenomenon before,
nor had a European expert who was consulted.
The most likely explanation is that the fox had eaten a prey species or other
food item that had run, fallen or been washed into a patch of soil and debris
where the tiny shells had been washed and accumulated as flotsam, and that the
fox had consumed the shells inadvertently. It is almost certainly not energy
efficient for a fox to seek out and consume 5 mm snails. Alternative theories
were not lacking, however. Shortly thereafter, Stephen Green found a small snail
shell caught in a bit of hair from a dead goat and suggested impishly that the
fox in question might have eaten a goat with snails attached.
Intriguing that the snail shells (made of calcium carbonate, CaC03) passed
through the fox intact. This was unexpected since calcium carbonate dissolves
readily in an acid environment like that of a mammalian digestive tract. Peter
Cunningham suggests this may be due to the fox's short digestion time, implying
a short residence time in the digestive tract for material consumed. But if the
shells were not dissolved, could the snails themselves have survived if they had
been ingested alive? And if so, is this a potentially unappreciated means of
dispersal for land snails?
The episode also suggests a future for forensic malacology. It was possible
to use the snail shells to identify the concerned fox dropping as having been
collected in the Ru'us Al-Jibal (as confirmed by Peter's notes), since two of
the three species are found only there and not further south in the UAE.
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Hajar Mountain Nature Hike
(Natural History)
Report by Gary Feulner with a little help from the editor of Gazelle
To our chairman's disappointment this nature hike was more hike than nature,
because the scattered showers in September and October were not enough to make a
great difference to the plant life in many areas. The plants may be dusted off,
but most are not revived. The hiking area seemed to have received only a
sprinkle of rain. One of the few plants seen in flower was the lavender,
Lavandula subnuda, which follows a strategy of "firing" its row of
buds one-at-a-time, so there's always a blossom - but often only one - on
display. Another was a lone specimen of the wispy mountain morning glory,
Convolvulus virgatus, perhaps fooled by the rain, which aimed three or four
white, funnel-shaped flowers towards the sun.
At the start of the hike was a natural spring and pool which previous field
trips have visited amidst lush vegetation of oleanders, wadi grass, reeds and
rushes. Sadly, all this had been cut and burned to facilitate the construction
of a concrete cistern, used as a water supply for new plantations, some two
kilometres downstream. A few toads had survived the destruction, but apparently
no wadi fish.
From their goal on the summit of Jebel Bulaydah, the group could see the
surrounding area, including the Masafi, the Masafi-Fujairah Road and the
plantations springing up along it, the white metamorphic rocks to the north, the
profile of Jebel Masafi. On top of Jebel Bulaydah a lone dragonfly paid a visit,
the pan-tropical Globe Skimmer (Pantala flavescens), a strong migrant.
From the ridge-top return route there were distant views of a group of four
large, soaring raptors. At a guess, based on colour pattern, they were probably
Booted Eagles.
To Gary's great surprise, one of the most popular photo opportunities seemed
to be the mummy of a dead donkey, still resting its head on a grassy pillow.
This was a rigorous hike where the ascent seemed to go on for ever and the
initial descent on loose skree was perhaps a lot faster than planned. It might
have been easier to sit on a large cushion and slide down. Everyone enjoyed the
day, and probably had the best night's sleep this year!
Special mention goes to Gary Feulner for ignoring the moans and groans behind
him, Richard Dennis for the most spring in his step (with Alan Buck as a
runner-up, at least downhill), Salah Al-Halyan for the best shortcuts, Paul
Callaghan for the longest nap at lunch, Gaye Harden for the most stylish hat,
and "Iron Mike" Lorrigan for best storytelling, with his recollections
of DNHG field trips past.
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Clam shrimps found at Hatta, too
(Natural History)
Report by Gary Feulner
Molly McQuarrie of the ENHG in Abu Dhabi read our reports in the Gazelle
about clam shrimps being found in mountain pools after recent rains in the
mountains NE of Al-Ain. While showing off the Hatta area to visitors, Molly
managed to find more clam shrimps in a small ephemeral pool in silt beside the
main wadi, just below Hatta village. Although one may question Molly's judgment
as a tour guide, this observation extends the known range of these organisms
locally (it is the northernmost report) and renews the question whether the
arrival of clam shrimps is recent, or whether observers have been missing them
all these years. They were first reported from Jebel Hafeet in 1999.
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New Site for Rare Pond Snail
(Natural History)
Report by Gary Feulner
Bulinus wrighti is the rarest of the UAE's native freshwater snails. It
represents a genus that may have originated in Arabia, although it is now
centred in Africa. It has attracted particular attention because the genus is a
potential host for schistosome parasites and B. wrighti itself is susceptible to
most schistosome strains. As a result, it is used for medical research;
specimens were collected for this purpose in September from one of two known
sites in the northern Hajar Mountains.
Coincidentally, a third site was discovered in the Ru'us Al-Jibal only last
month, in Wadi Naqab, just within the borders of the UAE, by a determined DNHG
party consisting of Barbara Couldrey, Nick Hepher, Peter Cunningham and Gary
Feulner. The site is a long pool carved in bedrock, more than 2 metres deep when
full, but now reduced to a small gravel puddle the size of a drinking cup.
Shells, but no live snails, were found.
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Shelling Report October/November 2000
(Marine Life)
Report by Dr. Sandy Fowler
Beryl and I checked out Rams beach on 27 October. It was in a terrible state.
Garbage everywhere and almost no shells. Patricia and Robert Rosetti had the
same experience the week before. We left in disgust after 2 hours.
I reported earlier taking a shell from a Khor Fakkan beach to the Natural
History Museum in June this year. It was identified as Latirus turritus, not
recorded before in UAE waters. I've found 3 more since, on the same beach, the
latest on the DNHG field trip of 10 November 2000.
For the Field Trip 10 November, a good turnout of shelling stalwarts turned
up at the beach north of Khor Fakkan, with an unlucky twosome undeterred by a
puncture in Masafi. Weather conditions, a perfect tide and a good mix of shells
should have let everyone collect at least 50 different species. I was lucky
enough to find a specimen of Volva volva previously unrecorded in Eastern
Arabia. With both ends of a beach to check out, the group quickly fragmented,
and I wasn't able to check everyone's finds individually. If anyone wants help
with identification, call me at home and I'll be glad to help if I can.
I checked out Hamriya beach this month. It's an easy 45-minute drive from
Dubai. There was a good mix of shells (I identified about 40 separate species),
and I was fascinated to see Terebralia embedded in rocks below the high water
mark. Is this why we're still finding them on the beaches? Are they truly
extinct within the Gulf? The hunt for live ones goes on!
One or two people have been asking for another shell workshop, where
interested shellers can get together at my home, compare finds, and maybe get
those stubborn shells identified. I provisionally hope to hold one in early
spring. If you are interested call me and put your name down for it; I'll
contact you when a date is fixed.
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Tahr on Jebel Hafit
(Mammals)
Report by Peter Cunningham
During a hike up to the summit wadi's on Jebel Hafit during October I
witnessed a rare event that made the unusual heat for this time of the year more
bearable. An adult male Tahr emerged unexpectedly out of a gully approximately
100m ahead of me. Recognizing it immediately I knew how privileged I was to see
this rare ungulate in its natural environment.
Arabian Tahr, Hemitragus jayakari, are endemic to the Arabian Peninsula and
occur in mountainous terrain throughout the eastern UAE and northern Oman, from
the Musandam in the north, to the mountains bordering the Wahiba Sands in the
south. The well-known Arabian explorer, Wilfred Thesiger, first documented them
from Jebel Hafit in 1949 and mentions them being regularly hunted by local Bedu
during that time. According to a study conducted on this species in Oman in the
late 70's, the Arabian Tahr world population did not exceed 2000 animals. A
helicopter survey of Jebel Hafit in 1980 sighted only 5 animals. During the 80's
they were thought to be extinct on Jebel Hafit as no sightings were reported.
Confirmed sightings are infrequent and they are classified as "critically
endangered" in the UAE (i.e. "facing an extremely high risk of
extinction in the wild in the immediate future").
This little known species is in direct competition with domestic and feral
goats for the available food. They are highly selective feeders mainly utilizing
the growth tips and fruits of certain shrubs. The carrying capacity of mountains
such as Jebel Hafit is generally low and the extra pressure of hunting (now
illegal although not enforced) and excessive goat numbers could lead to the
demise of this species in the wild if something drastic is not done to protect
them.
The individual I encountered was typical of males of the species with its
well-developed forequarters, prominent facial stripe, thick slightly curved
horns and dark-brown shaggy coat [A previous sighting I had of a female in the
Central Hajar Mountains had an overall slender build and "blonder"
appearance]. Initially it was unaware of me as I had the wind in my favour, and
had approached the rise I was on with care. As soon as I moved to get my camera
from my backpack it sensed me and loped off - not fleeing in fear - up the
mountain towards some inaccessible cliffs where I could not follow. As I was not
expecting to stumble upon Tahr, I was unprepared, but did eventually (after
having to change lenses in haste) get two photos of the Tahr just before it
disappeared over the crest. Unfortunately the distance involved as well as
midday lighting, did not make for a great photo and I am now trying to get the
subject enlarged. Although not detracting from the actual encounter of observing
Tahr at such close quarters, one thing I did however learn is to always be
prepared for the unexpected - next time!
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Facts about Bats
(Mammals)
Report by Peter Cunningham
Did you know:
- Nearly 1000 kinds of bats account for almost a quarter of all mammal
species and most are highly beneficial.
- A single bat can catch up to 600 mosquitoes in just 1 hour.
- Agricultural plants such as bananas, mangoes, dates and certain figs rely
on bats for pollination and seed dispersal.
- Bat droppings in caves support whole ecosystems of unique organisms.
- Contrary to popular belief, bats are not blind, do not become entangled in
human hair, bite only in self-defence, and seldom transmit disease to other
animals.
- Bats are exceptionally vulnerable to extinction, in part because they are
the slowest reproducing mammals on earth for their size with most producing
only one young per year.
- Only one species of "vampire bat" occurs in south and Central
America and does not suck blood, but makes an incision and then laps up the
blood.
- Very little scientific work has been conducted on bats from the UAE with
only 8 species ever recorded although it is suspected that many more may
occur.
I am busy doing some work on bat distribution in the UAE and would appreciate
information regarding the following:
- Bat roosts (i.e. caves/crevasses/ceilings, etc.)
- Bat gatherings (i.e. frequently used feeding areas or where seen often)
- Bat records (i.e. 16 Mouse-tailed Bats seen roosting at Abool Fort on 15
March 1999, etc.)
Any information regarding bats from the UAE & neighbouring Oman areas
could be useful. Any dead specimens and sculls, etc. could also be used for
identification purposes.
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Caralluma in Flower
(Botany)
With few exceptions, the showers that fell around the UAE in September,
October and early November have so far made little visible difference to the
parched landscape. It's nice to report, therefore, that at least a few Caralluma
arabica have been seen in flower, in the east (by Geoff Cosson) and west (by
Barbara Couldrey) of the Ru'us Al-Jibal. C. arabica is a succulent, leafless
milkweed that is easily mistaken for a cactus. The inflorescence is a globular
head of many small, deep wine-red flowers which are said to smell like rotting
meat.
A second Caralluma species with yellow flowers is found occasionally in the
area to the SW of Fujairah. There are no true cactuses native to the Old World,
but the prickly pear cactus (Opuntia sp.)
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