Spotted Ground Thrush

This rare bird is difficult to observe in the wild due to its silent and shy nature, and ability to freeze motionless when disturbed (4). Despite its elusiveness, the nest, generally a bowl constructed from vegetation, twigs, feathers and mud, tends to be exposed and easy to find. This results in predation by snakes, raptors and domestic cats, which accounts for 50 percent of breeding failures. The spotted ground-thrush has a low breeding success rate of 10 to 20 percent (2) (4). Typically, a clutch size of two to three eggs is laid and nests are often reused after a brood has fledged or failed. The breeding season is from September to March in South Africa and subspecies in Malawi have been found breeding in November (4). Foraging occurs mainly on the ground among leaf litter and on rotting wood (2), although the spotted ground-thrush can also be seen foraging amongst the lower branches of leafy trees. It feeds on invertebrates and their larvae, seeds, fruits and land molluscs (4), and nestlings are fed mainly on earthworms (2). Small home ranges used only for foraging are occupied by the spotted ground-thrush in its wintering grounds. Generally a solitary bird, it can be found in pairs or, on migration, in small parties (6).

The spotted ground-thrush is protected by its listing on Appendix II of the Convention on Migratory Species (CMS) (3). An International Action Plan for the spotted ground-thrush was produced by BirdLife International, with a five year plan set out. It is hoped the plan, due to end in 2010, will improve knowledge on the species' habitat requirements, breeding success and migration routes so that the population can be stabilised (4) (6).

As its name suggests, this mysterious bird is distinguishable by heavy black spotting on its white breast (4) (5). The upperparts are brownish with a band of white spots on the wing-coverts (2) (4). The face is whitish in colour with two black vertical stripes, one running through the eyes, and the other across the ear-coverts (2) (5). The legs are a fleshy-pink colour (3). There is slight variation between the five recognised subspecies, and juveniles are darker than adults with buff spotting on the head (2). The voice of this medium-sized bird is loud and melodic with flutey phrases of four to five notes (4) (5). It calls with a drawn out 'sreee' (4), and whilst foraging, a scarcely audible 'tsii-tsii' sound is made (2).

Found in forests of various types, from coastal forests in South Africa, to moist montane evergreen forests in Malawi (4) (6). The spotted ground-thrush has a preference for forests with nearly complete canopy cover and deep leaf litter (4) (6). It winters in tall coastal forests, and migratory populations use moist bush and thicket or coastal dune forest (6).

The spotted ground-thrush has a wide but discontinuous distribution (4). Zoothera guttata guttata is found in South Africa, Z. g. fischeri, a migratory coastal subspecies, is found in Kenya and Tanzania and Z. g. belcheri occurs in Malawi. The remaining two subspecies are known only from single specimens, with Z. g. maxis being found in Sudan and Z. g. lippensi in the Democratic Republic of Congo (4).

Classified as Endangered (EN) on the IUCN Red List 2007 (1). Listed on Appendix II of the Convention on Migratory Species (CMS) (3).

The destruction of spotted ground-thrush habitat has meant that the small and severely fragmented populations are in decline (4). Bush fires, deforestation and the spread of exotic species have continued to decrease the amount of suitable habitat (6). In South Africa, the wintering habitat has been destroyed by mining, and in the coastal forests of Tanzania which are used as 'stepping stones' in migration, charcoal production has degraded habitat (6). Despite habitat loss being the primary threat to the spotted ground-thrush, its recovery is also limited by its own poor breeding success (6).