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This
is a highly sought-after, nomadic bird that is by no means a guaranteed
find on a trip to its endemic region – the Karoo. Yet, despite varying
in abundance here, it remains fairly common throughout Bushmanland and
the dedicated birder does stand a good chance here of finding the rather
elusive bird.
As with many
birds in this region, knowledge of their favoured habitat is essential: Sclater’s
Larks occur largely on very stony substrate
with little vegetation. When walking through this habitat, be aware that
their inconspicuous yet distinctive flight call is an excellent way to
locate them. However, perhaps the best method of finding this lark is to
wait patiently near a water source adjacent to suitable habitat and
spend the otherwise unproductive heat of the day watching for birds
coming in to drink, usually in pairs or small groups.
It
is a small lark with a short conical and strong bill. Its wings are
relatively long, with the outermost primary less reduced than in
Calandrella. The plumage is
streaked on the crown and the back.
It prefers a habitat of open, well-grazed grasslands, semi-arid
and arid shrub-lands, desert grasslands and arid gravel plains. The nest
a cup, not domed, often with apron of nest material in the front.
Other
Names :
Sclater’s Short-toed Lark
It
is approximately 14 cm long and weighs around 19g. The sexes are alike
in appearance. It is small lark with a stocky build and large bill
giving a big-headed appearance. The upper parts are brownish buff,
broadly streaked with darker brown. The feathers have dark centres and
buff-brown edges. The Lores are whitish with an indistinct buff
supercilium and a dark line from the base of the bill through the eye
and around the ear coverts. Both sexes have a white crescent below the
eyes, under which is a dark brown ‘teardrop’ and a cup-shaped mark
with a short vertical streak below it. The chin and throat is white,
with a few brown speckles. The
rest of under parts are a rufuos-buff colour and the breast is streaked
brown. The tail is brown, with the outer web of outer 2-3 feathers
whitish and distinctive in flight. The bill is brownish pink to brownish
horn. The eyes are brown and legs light brown.
Juveniles
are paler and greyer than the adults and more spotted than streaked
above, with less distinct facial markings.
It
has a variety of short, melodious calls, including a peew, trew, tew,
trit, tchweet, trit-trit and trit-tew-tew-trit, given in flight or on a
perch
It
is endemic to South Africa and mostly confined to the Nama and Karoo. It
is most abundant on the vast, stony plains of Bushmanland, Northern
Cape, between Brandvlei and Pofadder, with localised records from as far
south-east as the Beaufort West district, to southern Namibia as far
north as the Mariental district.
It
is a Nomadic bird, presumably in response to localised rainfall events,
but the true nature of the relationship is obscure - conspicuous numbers
have been observed breeding at localities during both wet and dry
conditions. Over a 4 yr study at a locality in Bushmanland, the local
population was greatest and breeding, during a period of extreme
drought, and considerably smaller during a wet season.
It
is mostly found in gravely and stony arid to semi-arid plains with
scattered shrubs, grasses and extensive bare patches.
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They
are usually found in small, dispersed flocks of up to 25 birds when not
breeding. Generally seen in open areas, where it walks about with a
slow, plodding gait; rather cryptic and often only observed when
flushed; it is particularly associated with open areas of quartz gravel.
They normally fly approximately 3 m above the ground with a slow,
dipping flight, calling intermittently. It drinks frequently,
particularly when breeding.
It
forages in small, dispersed flocks; seeds are picked up from the ground
or stripped off low grasses and birds will turn over small, flat stones
to search for insects beneath them. It half crouches to peck vigorously
into the bases of dead Enneapogon desvauxii grass tufts, using the
heavy, sharply pointed bill to good effect in extracting large seeds
clasped in the basal leaf sheaths. It feeds on the seeds of a variety of
grasses (Brachiaria glomerata, E. desvauxii, Schmidtia kalahariensis,
Stipagrostis spp) shrubs (Fabaceae) and forbs (Polygonum spp) and
invertebrates, mainly harvester termites (Hodotermes), but also
Lepidopteran larvae, grasshoppers, ants (Messor capensis, Monomorium spp),
weevils and small beetles
The
bird is monogamous and is a solitary nester, but nests are placed as
close as 7 metres apart. Although nesting activity has been observed
after rainfall, the main breeding season falls within the driest time of
the year, even during extreme droughts. High mid-summer temperatures
probably preclude breeding from December to February.
The
nest is a neat cup of fine, dry leaves, stems and feathery awns of
grasses, usually Stipagrostis spp.
The inner cup diameter is between 47 and 59mm and a depth of
between 21 to 35mm. It is excavated by the bird, using its feet and
scattering the soil by wing fluttering. A rim of pebbles up to 8 cm
wide, comprising between 59 and 253 pebbles is often added. Most nests
are sited in completely exposed situations in bare patches of quartz
pebbles or shale gravel, far from shrubs or grass tufts, but always
within 1 km of a water source
They
invariably lay only 1 egg. It is oval to elliptical in shape and is
white or off-white in colour with brownish tinges and finely spotted
with greyish brown or speckled with brown and a few brown blotches over
underlying slate speckles. These markings are usually concentrated on
the obtuse end.
Incubation
of the eggs and nest care is done by both sexes. During hot, cloudless
weather, incubation shifts last between 11 to 65 minutes, with the
attending bird spending most of the time standing over the nest to shade
the egg, facing towards the sun or into a breeze and with feathers
raised and eyes half closed to reduce heat gain. It is reluctant to
leave the nest when it is very hot. When it is hot, the incubating bird
pants continuously and must fly to drink several times a day.
The
incubation period is not determined, but it is thought to be between 11
and 12.5 days.
Newly
hatched young has blackish skin with buff-coloured tufts of down on the
crown, back, wings and rump; The gape is yellowish and the inside of
mouth is orange-yellow and tongue spots are present. The first feathers
appear at 4 days and are replacing the down by 6 days.
The
chicks are unable to fly for several days after leaving the nest, and
move to the shade of a nearby shrub.
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