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The Namaqua Sandgrouse is found from the extreme south
western Angola to Namibia, Botswana and western South Africa. From the
West Coast to the Eastern Free State and Eastern Cape interior and as far
south as the wheat-lands of the south
western Cape.
It is a vagrant to Zimbabwe, Lesotho lowlands, KwaZulu Natal and Eastern
Cape seaboard.
Their movements are Nomadic. Southern populations are
partially migratory, especially in the Karoo. Populations in Namaqualand
and the Karoo are larger in summer (Sep-Apr), often disappearing during
winter (May-Aug), when populations in the southern Kalahari increase -
suggesting partial migration between these two regions. The possibility
that the Karoo birds migrate as far as north western Namibia during winter
requires confirmation. Two birds ringed near Kimberley were shot at the
same locality 1 and 2 years later, suggesting some site faithfulness. A
bird ringed at Gobabeb in April was recovered at Seeis (300km East) in
September of the same year.
Namaqua Sandgrouse prefer gravel desert and sandy
semi-desert, open arid and semi-arid dwarf scrubland with or without
grassland, sandy savannah with denser vegetation, but generally where
average annual rainfall is less than 300mm. They are most common in the
Nama Karoo, Namibian Escarpment and southern Kalahari vegetation types.
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It spends most of the day on the ground, in pairs or,
more usually, small flocks and feeds most intensively in early morning
and late afternoon, lying up in any shade during the mid-day heat. |
In flat country, birds concentrate in drainage lines, where
food is more abundant. It crouches when disturbed, flushing at a distance
of approximately 10m. It takes off explosively, flying fast and straight.
From 1-2hr after sunrise, flocks fly up to 60km each day to waterholes,
calling intermittently while travelling at a height of about 10m into
strong headwinds, otherwise 50-100m, with a cruising speed of 60-70km/h.
Smaller numbers drink in the late afternoon.
When not breeding, flocks gather around the waterhole for
half an hour before approaching to drink synchronously, sometimes in
flocks numbering thousands. Breeding birds drink without much delay in
smaller flocks. They prefer exposed waterholes with little surrounding
vegetation and do not drink brackish or salty water. The bird does not
perch, so cannot drink from troughs or reservoirs unless there is a leak.
In the late afternoon, sometimes as early as 2hr before
sunset, flocks fly to roosting sites in stony areas, where each bird makes
a shallow roosting scrape in which it spends the night. In the southern
Kalahari, flocks congregate in large communal roosts on raised, rocky
ground. Roosting birds may huddle tightly together in cold weather, with
adjacent birds facing alternate directions. Birds dust-bathe frequently,
but never bathe in water.
Namaqua Sandgrouse feeds during daylight hours, singly, in
pairs or groups. It walks slowly with head bent low, making rapid pecks
at the ground. It does not scratch with its feet, but will flick sand
with the bill. They feed almost exclusively on seeds, mostly the small,
hard seeds of ephemeral plants, with occasional fresh leaves, flowers and
small fruits e.g. Lyceum. It prefers protein-rich legume seeds, feeding
mainly on Indigofera in the Nama Karoo, Lotononis in the Succulent Karoo,
Tephrosia in the Namib and Tephrosia and Requernia sphaerosperma in the
southern Kalahari.
Other important food plants are Limeum, Gisekia
pharnacioides, Amaranthus Cleome, Chenopodium and Lophiocarpus burchelli.
Seed from the grass (Poaceae) and daisy (Asteraceae) families is rarely
eaten. Grit and pebbles are eaten intentionally to assist grinding up the
seeds in the gizzard. A full crop (up to 24ml volume) contains between 3
000 and 40 000 seeds, depending on seed size. The birds fill their crops
before flying to roost in the late afternoon.
They are solitary nesters, but are not territorial. They do
not partake in elaborate courtship displays. They lay any time of the
year, but mostly between January-May in the northern Namib, April-July in
southern Namib, June-November in the Kalahari, August-January in the Nama
Karoo and September-February in Namaqualand and south western Cape. The
timing does not correlate with rainfall or food availability in some
regions. |
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The nest is a
simple scrape in the ground, usually exposed to the elements but adjacent
(within 30cm) to low disruptive objects. The scrape becomes filled with
grit and plant matter as incubation proceeds. The pair selects the nest
site together, but the role of the sexes in digging out the scrape is
unrecorded.
They lay 2-3 eggs. These are laid at 2 day intervals. No
geographical or seasonal variation in clutch size has been detected. Eggs
are elliptical in shape and are pale greenish or pinkish stone with both
pale grey and either olive-brown or reddish brown speckles, spots or
sometimes large blotches. These markings may be concentrated in a ring at
one end. Incubation begins once the clutch is complete and is continuous,
by both sexes. The incubating bird generally crouches on nest when
disturbed, flushing at a distance of 3-5m. Incubation is normally around
21 days from clutch completion.
Chicks usually hatch synchronously within 24 hours of each
other and weigh around 7g once dry. Hatching never occurs at night.
Eggshells are removed from the nest and vicinity by the adults. The crown
and back of the downy chick is patterned yellowish brown with narrow
crossbars of white outlined with black, forming a diffuse double
figure-of-8 pattern on the back. The undersides are a pale buff colour
and becoming darker on the breast. Chicks are led away from nest within 12
hours of the last chick hatching, to feeding sites. Chicks feed themselves
within 24 hours of hatching, eating only seeds. The parents initially
show the chicks the food and what is edible.
For the first two months, the male carries water in soaked
in his belly plumage for the chicks to drink from. When chicks are very
small, parents take turns flying to the waterhole, but as young grow, the
pair fly together leaving young crouched in the shade of a plant. Chicks
are closely attended by parents and crouch motionless next to an object or
under cover in response to parent’s alarm calls if a predator approaches.
At around 21 days chicks are almost fully feathered but
can’t fly, although they use wings for balance when running. They can fly
few metres at around 30 days and fly capably at around 42 days. Young fly
to waterholes with parents for 1st time when around 2 months old and moult
into adult plumage. The post-fledging dependency period is at least 1
month.
The birds are common sight, with a widespread distribution
that is well represented in protected areas, particularly in Namibia. The
sinking of boreholes by farmers since the 1930's has increased water
availability in arid habitats and thus the area available to Namaqua
sandgrouse, probably resulting in population increases.
The male’s head, mantle and breast is yellowish olive,
yellower on the throat and forehead with a double breast-band of white and
deep maroon. The belly is dark brown with the back and some wing covert
feathers brownish olive and the apical 3rd a pale buff colour and a
pearly-grey apical spot. Many wing coverts are edged on the inner vane
with a dull chestnut.
The female’s head and upper breast is streaked dark brown
and buff and the throat is plain yellowish with the upper breast streaked
dark brown and the body and belly barred brown and buff.
Juveniles are similar in colour to adult females but are
more finely barred with the belly a plain rufous colour in male but more
mottled and barred with dark brown in the female.
When in flight they give a loud, nasal ‘ki-ki-vee’ (‘kel-kie-wyn’)
repeated at short intervals and as a contact call between birds on the
ground and over-flying birds. Large flocks keep up a continuous muttering
of ‘kip’ notes on the ground at a waterhole and give a rapid
‘kip-kip-kip-kip’ on take-off. They give a strident ‘ki-kiii’ alarm call
when flushed off the nest and a high-pitched, chirring distraction call
when birds perform an injury-feigning distraction display near eggs or
young. Parents summon their chicks with soft ‘quip’ notes, similar to the
muttering of flocks at water. |
