Geographical variation in Desert Lark Alauda
deserti is complex, and numerous races have been named mainly on the basis
of plumage coloration. The colour of the
birds appears to be directly related to the colour of the local soil and rocks
with birds from sandy habitats are mostly buff-coloured, those of stony or
rocky ground various shades of grey, rufous, or brown with blackish
races living in black lava deserts. Confusingly, pale and dark birds occasionally
live side by side in some areas and bleaching and abrasion have marked effect on
colouration and produce further complications often making sub-specific
identification difficult. The races occurring in Saudi
Arabia include nominate A. d. deserti
that occurs locally in the Nile valley between northern Sudan and central Egypt
and has also been recorded from the Red Sea coasts of Egypt, southern Sinai,
Jordan, and Tabuk and Ha'il in northern Saudi Arabia with birds being dark
grey-brown or brownish-grey above, like whitakeri, but much smaller and with an
almost wholly dark tail. A. d.
samharensis occurs along the Red
Sea coasts of Sudan, Eritrea and the Arabian Peninsula south to the Yemen
border and is much darker, dark grey-brown above, sandy buff below when
compared to isabellinus with those named
samharensis Shelley, 1902, and hijazensis Bates, 1935 appearing
inseparable. A. d. isabellinus occurs from northern Egypt, east to south and
east Israel, southern Jordan, north-west Saudi Arabia and southern Iraq and is
small and pale, generally light sandy to pale buff-brown with greyish or pale
olive-grey tinge above, buff or creamy buff below, tail rufous with triangular
black area at tip. Birds presumably of this subspecies occur throughout northern
Saudi Arabia gradually becoming plaler towards the east becoming pale cream
similar to azizi. A. d. azizi occurs
in northeast Saudi Arabia around the Hufuf and Shedgum areas and is the palest
race with pale creamy plumage. A.
d. saturata occurs in black lava deserts of southern Arabia from the northern
Hijaz to Aden and is very like samharensis, but the bill is longer and
stouter. Birds from Saudi Arabia are
smaller in size than those occurring in Africa. I have taken photographs of a
number of different looking Desert Larks from various parts of Saudi Arabia
some of which are shown below. Sub-specific identification can be difficult but
I have tried to put names to them. It is clear there is some difference between
colouration, bill size and tail colour of many of the birds in Saudi Arabia but
how much of this is clinal is unknown.
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Desert Lark samharensis (pale-hijazensis) - Taif |
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Desert Lark deserti - Tabuk |
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Desert Lark isabellinus - Thumamah |
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Desert Lark isabellinus - Jebal Nayriyyah |
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Desert Lark azizi - Shedgum |