Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The overall trend is decreasing, although some populations may be stable (Wetlands International 2006).
Behaviour This species is sedentary in West Africa and Madagascar but partly migratory elsewhere (Scott and Rose 1996), undertaking regular but unpredictable (del Hoyo, et al. 1992) short-distance movements (up to 700 km) in southern and eastern Africa in response to changing water levels (Scott and Rose 1996). It breeds in single pairs in all months of the year (dependant upon local rainfall) (Brown, et al, 1982), and remains in small groups even outside of the breeding season, although large aggregations have been recorded rarely (Madge and Burn 1988, Kear 2005b). Adults undergoing wing moult have been recorded in August-September in Zambia (Scott and Rose 1996). The species is crepuscular, being active usually only at dusk and dawn (Madge and Burn 1988, Kear 2005b). Habitat This species frequents shallow, freshwater marshes, swamps, pools and lakes, feeding at muddy edges and amongst submerged, floating (water-lilies) and emergent (Papyrus, reeds - Phragmites spp., bullrushes - Typha spp.) vegetation (Madge and Burn 1988, del Hoyo, et al. 1992, Kear 2005b). It may occasionally be seen on more open lakes and reservoirs (Madge and Burn 1988), or sewage pans (Brown, et al, 1982, Hockey, et al. 2005), and will feed on land in flooded fields, rice paddies and waterside areas heavily disturbed by wild ungulates or cattle (Kear 2005b). During the dry season this species regularly occurs in small numbers on small scattered pans in semi-arid regions (Scott and Rose 1996). Throughout the day the species often sleeps on open water or in quiet marshy backwaters (Johnsgard 1978, Kear 2005b), and may also rest on land (Brown, et al, 1982). Diet This species is omnivorous (Kear 2005b), as although its diet consists largely of seeds (especially of the grass Sacciolepis) (Johnsgard 1978), fruits and other vegetable matter, it may take aquatic invertebrates such as crustaceans, molluscs, water insects such as beetles and the larvae of flies (especially if these are super-abundant) (Johnsgard 1978, Brown, et al, 1982, del Hoyo, et al. 1992, Hockey, et al. 2005, Kear 2005b). Breeding site Nests are built from surrounding vegetation and well hidden above water in drowned trees, Phragmites or Typha reeds, Cyperus sedge or in Papyrus clumps (Brown, et al, 1982, Madge and Burn 1988, Kear 2005b). Usually this species nests singly, but pairs will sometimes nest close together (Brown, et al, 1982).
Habitat degradation (e.g. wetland conversion by commercial and subsistence agriculture in South Africa) (Hockey, et al. 2005) is the main threat to this species, so the protection of wetlands and waterside vegetation (also deliberately burnt in South Africa) (Hockey, et al. 2005) is necessary to maintain populations (Kear 2005b). Utilisation This species is hunted (e.g. it is hunted for local consumption and trade at Lake Chilwa, Malawi) (Bhima 2006), and although hunting at current levels does not threaten the species (del Hoyo, et al. 1992, Scott and Rose 1996, Kear 2005b), a control of hunting practices may be necessary in the future to maintain population sizes at current levels (del Hoyo, et al. 1992, Kear 2005b).
Text account compilers
Ekstrom, J., Butchart, S., Malpas, L.
BirdLife International (2020) Species factsheet: Spatula hottentota. Downloaded from http://www.birdlife.org on 11/07/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 11/07/2020.