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 under 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). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (under 10,000 mature individuals with a continuing decline estimated to be over 10% in ten years or three generations, or with a specified population structure). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (over 30% decline over ten years or three generations). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size is estimated at 1,000,000-1,000,001 individuals (Wetlands International 2023), which equates to 667,000-667,000 mature individuals. The overall population trend is suspected to be stable over three generations (11.64 years) (Wetlands International 2023).
Trend justification
.
Behaviour This species is sedentary and a local migrant, its movements related to seasonal rainfall and the filling up of temporary waters (Urban et al. 1986, del Hoyo et al. 1996, Taylor and van Perlo 1998). Young birds may also undergo extensive dispersal movements that are not linked to rainfall (Taylor and van Perlo 1998). The species may breed throughout the year when conditions are suitable, with seasonal peaks during or following periods of rain (del Hoyo et al. 1996). It nests territorially (Urban et al. 1986), and is usually observed in pairs, but may gather in groups of up to 10 individuals (Urban et al. 1986, Hockey et al. 2005). The adults may become flightless for up to 3 weeks between December and March when moulting their fight feathers (Urban et al. 1986), during which time they remain within the cover of waterside vegetation (Hockey et al. 2005). The species is active diurnally, with peaks of activity occurring just after rainfall (Urban et al. 1986). Habitat The species inhabits many types of wetland, although it requires moderate vegetation cover, some degree of permanent flooding (Urban et al. 1986, del Hoyo et al. 1996, Taylor and van Perlo 1998), and tangled vegetation in which it can climb, roost and nest (del Hoyo et al. 1996, Taylor and van Perlo 1998). Suitable habitats include flowing and still inland freshwaters (del Hoyo et al. 1996, Taylor and van Perlo 1998) (such as lakes, ponds, reservoirs, seasonal pans and temporary flooded areas along rivers) (Urban et al. 1986, Taylor and van Perlo 1998), the margins of coastal lagoons (Ghana) (Taylor and van Perlo 1998) and estuarine waters (Hockey et al. 2005); preferably fringed by rank grass, sedges, reedbeds, papyrus, swampy thickets, bushes or other vegetation (Urban et al. 1986, del Hoyo et al. 1996, Taylor and van Perlo 1998). The species also inhabits ponds with floating submergent vegetation (e.g. water-lilies) (Urban et al. 1986, del Hoyo et al. 1996, Taylor and van Perlo 1998) and the interior of dense or extensive reedbeds (Taylor and van Perlo 1998), as well as dense undergrowth in boggy forest clearings (del Hoyo et al. 1996, Taylor and van Perlo 1998), or the margins of swampy forest streams (Urban et al. 1986). In more open areas it may inhabit broad, grassy marshes (Urban et al. 1986, del Hoyo et al. 1996) and will occupy very small streams with little cover in drier regions (del Hoyo et al. 1996). Diet The diet of this species consists of worms, molluscs, crustaceans, adult and larval insects, small fish (Urban et al. 1986, del Hoyo et al. 1996), small frogs and tadpoles (del Hoyo et al. 1996), the eggs and nestlings (Urban et al. 1986, del Hoyo et al. 1996) of weavers Ploceus spp. and herons (e.g. Rufous-bellied Heron Ardeola rufiventris) (Taylor and van Perlo 1998), as well as the seeds and other parts of water plants (Urban et al. 1986, del Hoyo et al. 1996) (e.g. duckweed Lemna and water-lilies Nymphaea) (Taylor and van Perlo 1998) and occasionally carrion (Urban et al. 1986, del Hoyo et al. 1996). Breeding site The nest is a deep bowl of reeds and other aquatic plants that is usually placed floating on or suspended 20-50 cm above the surface of water in vegetation (Urban et al. 1986, del Hoyo et al. 1996, Taylor and van Perlo 1998, Hockey et al. 2005). Nests may also be placed on the ground or in grass tussocks near water, and occasionally up to 3 m high in bushes (del Hoyo et al. 1996, Taylor and van Perlo 1998).
Utilisation The species is hunted for trade (at traditional medicine markets) in Nigeria (Nikolaus 2001), and for local consumption and trade at Lake Chilwa, Malawi (Bhima 2006).
Text account compilers
Rutherford, C.A.
Recommended citation
BirdLife International (2024) Species factsheet: Black Crake Zapornia flavirostra. Downloaded from
https://datazone.birdlife.org/species/factsheet/black-crake-zapornia-flavirostra on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.