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 200,500-1,202,500 individuals (Wetlands International 2023), which equates to 134,000-802,000 mature individuals. The overall population trend is considered to be stable over three generations (21.51 years) (Wetlands International 2023).
Trend justification
.
Behaviour This species is a sedentary resident and partial migrant, making irregular movements (Hockey et al. 2005)in response to changes in local water conditions, especially with the rising and falling of flood-levels (del Hoyo et al. 1992). The breeding season varies geographically, although most breeding peaks are associated with periods of rainfall (Johnsgard 1993) or flooding (del Hoyo et al. 1992). The species breeds in association with other waterbird species (del Hoyo et al. 1992, Nelson 2005), usually nesting in small numbers (1-5 pairs) amid much larger mixed-species colonies (Brown et al. 1982, Langrand 1990). It generally fishes singly (Brown et al. 1982, Langrand 1990, del Hoyo et al. 1992) or in small groups in shallow water by day (Brown et al. 1982, Langrand 1990), with peaks of activity in the early morning and late afternoon (Brown et al. 1982, Nelson 2005), occasionally also hunting cooperatively in loose associations with conspecifics or other species (Hockey et al. 2005, Nelson 2005). It commutes to foraging areas singly or in loose flocks (Hockey et al. 2005), and roosts nightly in large numbers (e.g. several thousands), often in mixed-species groups (Brown et al. 1982). During droughts the species may concentrate on permanent water-bodies, such as large rivers (del Hoyo et al. 1992). Habitat The species shows a preference for sheltered waters with fringing vegetation, emergent trees (del Hoyo et al. 1992, Nelson 2005) and gently sloping shores (Hockey et al. 2005), preferring to fish in shallow water c.2 m deep (Brown et al. 1982, Hockey et al. 2005, Nelson 2005), and within c.100 m of the shore (Nelson 2005). It is quick to colonise temporary flood-waters (del Hoyo et al. 1992), and will frequent most freshwater habitats except fast-flowing streams (Hockey et al. 2005), commonly roosting in Typha or Phragmites beds, or on partly submerged bushes or trees (Brown et al. 1982). Habitats include large and small slow-flowing rivers (Brown et al. 1982, del Hoyo et al. 1992, Nelson 2005), lagoons (del Hoyo et al. 1992, Hockey et al. 2005), ponds (Brown et al. 1982, del Hoyo et al. 1992), small farm dams, creeks, lakes (Nelson 2005), swamps (del Hoyo et al. 1992, Nelson 2005) and thickets of scrub or stands of trees within sedge-filled areas of water (Nelson 2005). It is occasionally observed on inland alkaline lakes (Brown et al. 1982, del Hoyo et al. 1992) and on freshwater wetlands along the coast (del Hoyo et al. 1992) (e.g. coastal lagoons) (Brown et al. 1982, Nelson 2005), and sometimes frequents rocky shores (Nelson 2005), inshore islands (Nelson 2005) with rocky outcrops and flats (Johnsgard 1993), mangrove swamps (Brown et al. 1982, del Hoyo et al. 1992, Nelson 2005), estuaries (Brown et al. 1982, del Hoyo et al. 1992, Hockey et al. 2005) and sheltered coastal waters (Hockey et al. 2005). Diet This species is a generalist, taking any slow-moving prey (Hockey et al. 2005). In estuaries, coastal lagoons and large inland lakes its diet is dominated by fish of up to 20 cm long, especially cichlids (Haplochromis, Pseudocrenilabrus and tilapia Sarotherodon) (Brown et al. 1982, del Hoyo et al. 1992), but at smaller water-bodies frogs, crustaceans, aquatic insects (Brown et al. 1982, del Hoyo et al. 1992), molluscs and occasionally small birds (Brown et al. 1982) are more important (Hockey et al. 2005). Breeding site The species nests in mixed-species colonies, with nests scattered throughout the group, often nearer water than the other species (Brown et al. 1982). The nest is a platform of twigs and other vegetation built 0.5-6 m above the ground (Brown et al. 1982), although the height of the nest is influenced by water-levels (it breeds higher in trees when water-levels are low, to reduce the risk of predation) (Hockey et al. 2005). Nesting sites include the forks of trees (often partly submerged, over water or on islands) (Hockey et al. 2005), reedbeds (Brown et al. 1982, del Hoyo et al. 1992, Hockey et al. 2005), sand (Nelson 2005) and tufts of vegetation on the ground (Brown et al. 1982), or cliffs and rocky outcrops on coastal islands (Hockey et al. 2005, Nelson 2005). Management information Three artificially constructed heronries in a man-made wetland at Blouvlei (Western Cape, South Africa) attracted a number of nesting pairs of this species which proceeded to breed successfully (Harrison et al. 2001). The heronries were erected in open water (the centre of a pond), and took the form of rectangular frameworks anchored by sunken corner posts, with natural poles and branches of dead wood arranged and secured within them to imitate natural thickets (Harrison et al. 2001). No decoy birds or nests were used (Harrison et al. 2001).
This species is persecuted in some areas of southern Africa because of its local (insignificant) impact on trout (Salmo spp.) and other recreational fish stocks (Hockey et al. 2005). The species may also be declining at Lake Naivasha, Kenya as a result of increased disturbance by fishermen along the lake shore (this species's primary feeding location) (Childress et al. 2002).
Text account compilers
Rutherford, C.A.
Recommended citation
BirdLife International (2024) Species factsheet: Long-tailed Cormorant Microcarbo africanus. Downloaded from
https://datazone.birdlife.org/species/factsheet/long-tailed-cormorant-microcarbo-africanus 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.