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Dune Lark - Namibia’s only truly endemic Bird

Avatar of inke inke - 29. July 2016 - Discover Namibia

The Dune Lark: Occurs only in Namibia. Photo: Eckart Demasius

The Dune Lark is one of the most desert-adapted birds in the world. It lives on sparsely vegetated sand dunes in the Namib. It does not drink water and it feeds on whatever seeds and insects it can find.

It has a number of interesting behaviour patterns that help it survive in the intense heat and aridity of the Namib sand dunes. It searches for food mainly in the morning and late afternoon, running rapidly over the bare sand between patches of vegetation. The hotter it gets, the longer are the bird’s strides. During the heat of the day Dune Larks disappear into the base of large shady grass clumps. They rest within these clumps usually a few centimetres above the ground to benefit from the cooling effect of any breeze. Temperature measurements in the central Namib show that at 13h00 when the temperature of the sand is over 50° Celsius the lark’s resting place is about 33°. The birds thus avoid contact with the hot sand and radiation from the ground and sun and in this way minimise their water loss to evaporative cooling.

When it comes to breeding Dune Larks also have some interesting desert adaptations. They build domed nests which provide shade for the female on nest duty and for her eggs or young. The nest is placed on the sand at the base of a plant, usually at or near the top of a hummock or dune and with the nest entrance facing southeast. This creates the best shade and cooling effect from the prevailing wind.

The Dune Lark Calendulauda erythrochlamys was formerly known as the Red-mantled Lark, the literal meaning of its specific scientific name. It was probably first collected in the Rooibank area of the Kuiseb River where it still occurs today. Its distribution is entirely contained within the Namib sand sea in Namibia, ranging from the Kuiseb River in the north to the Koichab area near Lüderitz in the south. It avoids the totally unvegetated dunes near the coast in the central Namib dune belt. Most of its range is in the Namib-Naukluft Park. Only the extreme eastern parts of its range spill over into adjacent freehold land. Much of this land is now under private conservation management, such as in NamibRand Nature Reserve and Gondwana Namib Park. Almost the entire global population of the Dune Lark is thus protected on land managed for conservation.

The Dune Lark is closely related to three other lark species endemic to southern Africa, namely Barlow’s Lark which is a near endemic to Namibia and which occupies a very small range in the Succulent Karoo ecosystem on the coastal plains from near Lüderitz to Port Nolloth in South Africa; the Red Lark, also a range restricted species endemic to the red sand dunes of the northern Cape; and the Karoo Lark, endemic to South Africa from the Richtersveld south to the Great and Little Karoo, but which will probably be found to occur in the southern parts of Namibia when this area is more thoroughly investigated.

The Dune Lark needs as least 20-30 percent of its diet as invertebrates to metabolise enough water to survive. Apart from its breeding biology, little research has been carried out on this lark. One limited study on its diet in the mid 1960s, based on the stomach contents of 19 birds, showed that by volume, 32 percent comprised seeds and 68 percent invertebrates. Nearly all the seeds were Stipagrostis grasses while most of the invertebrates were large sugar ants and termites. Other invertebrates included locusts, beetles, caterpillars and a White Lady Spider.

There are 16 endemic and near-endemic bird species in Namibia. The Dune Lark is Namibia’s only truly endemic bird species, where its entire global population is contained within the borders of the country. A near endemic is one for which at least 90 percent of a bird’s global population occurs within the country. Namibia has a special responsibility to the conservation of its endemic and near-endemic species: if we don’t look after them no one else can. Fortunately the Dune Lark is well protected within Namibia's national and private parks system.

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