Anyone who has spent an evening in the Namib Desert or in the Kalahari must have heard the loud call of a barking gecko, especially during the summer months. Most visitors think that a bird must be responsible for the repetitive keck-keck-keck-keck-keck sounds. But it is a gecko, about six centimetres long, which lives in a burrow of up to a metre with numerous tunnels and at least one escape exit.
Namibia is the only country with three types of barking geckos. Carp’s barking gecko (Ptenopus carpi), named after Dutch-born South African amateur naturalist, Bernhard Karp (1901 – 1966), and Koch’s barking gecko (Ptenopus kochi), named after the founder and first director of the Gobabeb Desert Research Station, Carl Koch (1904 in Vienna – 1970 in Windhoek), are endemic to Namibia. The common barking gecko (Ptenopus garrulus) is endemic to all of southern Africa and occurs in the arid areas of Namibia, Botswana, South Africa and a small part of southern Zimbabwe. Ptenopus garrulus is divided into two subspecies: Ptenopus garrulus garrulus is slightly smaller and lives in the sandy parts of the Kalahari Desert in Namibia, while Ptenopus garrulus maculatus is found in the southern as well as the central western parts of Namibia and in the Namib Desert.
Only males utter the characteristic calls – to attract females and/or mark their territory. While calling they sit in the entrance to their burrow. In case of danger they can reverse into it in a flash. These small, well-camouflaged geckos are nocturnal. When termites take to flight, the geckos will leave their burrow and actively hunt for the insects. Otherwise, barking geckos mostly remain in the entrance of the burrow and simply wait for prey. Sometimes they slowly move across the sandy plain in search of a meal. When danger is encountered they will sit tight motionless.
Carp’s barking gecko is found on the gravel plains of the Namib Desert north of the Kuiseb River. This well-camouflaged striped species calls up to 20 times, but usually 12 times. Koch’s barking gecko, which inhabits the sandy areas south of the Kuiseb, has tiny scales and the body is just slightly longer than the tail. The common barking gecko calls up to 13 times, but usually five times. The males of all three species have a yellow heart-shaped spot at the throat. Among the animals that prey on barking geckos are snakes, owls and mongooses. The females lay one or two hard-shelled eggs in a tunnel of the burrow.
Author: Dirk Heinrich