|Scientific Name:||Phalacrocorax capensis|
|Species Authority:||(Sparrman, 1789)|
|Taxonomic Source(s):||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.|
|Red List Category & Criteria:||Endangered A2bc+3bc+4bc ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Coetzee, R., Cook, T., Crawford, R., Kemper, J., Makhado, A., Thomas, R. & Wanless, R.|
|Facilitator/Compiler(s):||Anderson, O., Ashpole, J, Moreno, R., O'Brien, A., Symes, A., Taylor, J.|
This species is Endangered as key colonies in South Africa and Namibia have undergone rapid population declines over the past three generations. Declines are primarily believed to have been driven by collapsing epipelagic fish stocks, but the species is also susceptible to oiling and avian cholera outbreaks. This trend currently shows no sign of reversing, and immediate conservation action is required to prevent further declines.
|Previously published Red List assessments:|
Phalacrocorax capensis is endemic to southern Africa, where their usual non-breeding range extends from Lobito, Angola (12º S), on the west coast to Maputo Bay (formerly Delagoa Bay), Mozambique (25º S), on the east coast (Cooper et al. 1982). They breed from southern Angola to South Africa’s Eastern Cape province (Cooper et al. 1982; Dean et al. 2002), almost exclusively within the area of jurisdiction of the Benguela Current Commission (BCC), which extends from 5º S off Angola to 27º E off South Africa mostly to the west of Cape Agulhas (the southernmost tip of Africa, Crawford et al. 2016). The only known record of breeding outside this area is of at least one nest at Hole-in-the-Wall, Eastern Cape, in 1925 or 1926 (Cooper et al. 1982). Up until 1977–1981, this species only bred in Namibia and South Africa (Cooper et al. 1982). By 1996, they had extended their breeding range northwards into southern Angola (Dean et al. 2002). After the 1980s there were substantial decreases in numbers breeding in Namibia and northwest South Africa (Crawford et al. 2007, 2014, 2015, 2016). Since the commencement of the 21st century off southern South Africa some new colonies have formed and some have increased (Crawford et al. 2015, 2016). Therefore, there has been a significant adjustment in the spatial distribution of breeding with increases in the north and south and decreases in the centre of the species’s range. The altered distribution off South Africa was associated with an eastward displacement of the main prey of Cape Cormorants in South Africa, the epipelagic anchovy Engraulis encrasicolus and sardine Sardinops sagax (Hockey et al. 2005, Crawford et al. 2014, 2015). The most recent available estimates are of c.2,600 pairs in Angola in 2005 (Dyer 2007), c.57,000 pairs in Namibia in 2005 (Crawford et al. 2007, Kemper and Simmons 2015) and c.57,000 pairs in South Africa in 2010–2014 (Crawford et al. 2016). Therefore, the present best estimate of the global population is c.117,000 pairs, which equates to c.234,000 individuals.
Native:Angola (Angola); Congo; Mozambique; Namibia; South Africa
|Range Map:||Click here to open the map viewer and explore range.|
The most recent available estimates are of c.2,600 pairs in Angola in 2005 (Dyer 2007), c.57,000 pairs in Namibia in 2005 (Crawford et al. 2007, Kemper and Simmons 2015) and c.57,000 pairs in South Africa in 2010–2014 (Crawford et al. 2016). Therefore, the present best estimate of the global population is c. 117,000 pairs, which equates to c.234,000 individuals.
Trend Justification: In Namibia the population decreased by 57% over the three most recent generations and is classified as Endangered (Kemper and Simmons 2015). In South Africa, the population also decreased by > 50% during the three most recent generations and is classified as Endangered (Cook 2015, Crawford et al. 2016). The trend in Angola is unknown. However, Angola holds only c.2% of the present global population (see above).
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Behaviour This species is mainly sedentary but shows extensive post-breeding dispersal to the north and east of its breeding range, with birds reaching the mouth of the river Congo and southern Mozambique (del Hoyo et al. 1992, Johnsgard 1993) and individuals moving up to 1,430km (Johnsgard 1993). It is thought that the birds follow the movements of schooling fish (Crawford and Shelton 1978, Johnsgard 1993). It is a highly gregarious species which breeds in vast colonies of up to 120,000 birds (Nelson 2005). Egg-laying occurs throughout much of the year, with a peak usually in September and October (del Hoyo et al. 1992, Johnsgard 1993), continuing to February in Namibia (Johnsgard 1993). However the level of breeding activity is highly dependent on food supply: breeding will fluctuate depending on prey availability (Berry et al. 1979, Crawford and Dyer 1995) and will even cease if prey becomes scarce (Johnsgard 1993, Nelson 2005). It usually forages in large aggregations, often co-operatively and in association with other seabirds (Johnsgard 1993, Nelson 2005), although solitary foraging is also known to occur (Johnsgard 1993). Birds may fly up to 40km to a feeding location (Nelson 2005). Birds will dive to a maximum depth of 37 m (mean: 11 m) and forage off shoaling fish near the seafloor or in the water column (Cook et al. 2012).|
Habitat This species is usually found in the Benguela current less than 10 km from the coast (del Hoyo et al. 1992), although it does occasionally range as far as 70km offshore. During both the breeding and the non-breeding seasons it inhabits cliffs and ledges on the mainland and on offshore islands (Nelson 2005). It is occasionally found in the brackish waters of coastal lagoons, estuaries and harbours (del Hoyo et al. 1992), but does not use these habitats for breeding. It occurs in highest densities in areas of suitable habitat near the recruitment grounds for pilchards (Clupeidae) and anchovies (Engraulidae.) (Crawford and Shelton 1978).
Diet Its diet consists almost entirely of pelagic schooling fish, although it will occasionally take some invertebrates including crustaceans, molluscs and cephalopods (Rand 1960, Nelson 2005). South African Pilchards Sardinops ocellata and Cape Anchovies Engraulis japonicus capensis are often reported to be by far the most significant prey species throughout its range (Johnsgard 1993), but preferences appear to be subject to seasonal variation depending on the relative abundance of different fish species (Duffy et al. 1987, Crawford and Dyer 1995). Sandeels Ammodytes spp., Pelagic Gobies Sufflogobius bibarbatus and Maasbanker Trachurus trachurus may comprise the major food source under some circumstances (Cooper 1985, del Hoyo et al. 1992, Johnsgard 1993, Nelson 2005).
Breeding Site Breeding occurs mainly on cliffs and ledges, and flat inland areas of offshore islands (Nelson 2005). Caves, estuarine sand islands, guano platforms and other artificial structures are also used as breeding sites (Johnsgard 1993, Nelson 2005). Nests are constructed from seaweed, sticks and stems, and occur in high density (roughly 3 nests per square metre) within large colonies (Nelson 2005). Normally two or three eggs are laid, although the clutch-size ranges from one to five. The incubation period is 22-28 days, and the chicks fledge after about nine weeks. Post-fledging care is provided for several weeks. The oldest ringed bird was at least nine years old (del Hoyo et al. 1992).
|Continuing decline in area, extent and/or quality of habitat:||Unknown|
|Generation Length (years):||9.25|
|Movement patterns:||Not a Migrant|
|Congregatory:||Congregatory (and dispersive)|
Recent rapid declines are likely to be primarily driven by a shortage of good quality food near breeding localities resulting from commercial overfishing and environmental change (Crawford et al. 1992a, 2007, 2014, 2015, 2016).
Disease (especially avian cholera) has caused high mortality (Crawford et al. 1992a, Barnes 2000, Waller and Underhill 2007). Oil pollution is also a potential threat (Barnes 2000). In the past, guano mining caused considerable disturbance and declines (del Hoyo et al. 1992). Predation by Cape Fur Seal (Arctocephalus pusillus) on fledglings has increased as the seal has become more abundant owing to successful conservation measures (David et al. 2003), and has been found to represent a significant mortality factor for this species on Dyer Island, South Africa (Marks et al. 1997, Makhado et al. 2013) and Ichaboe Island, Namibia (Du Toit et al. 2004). It probably affects the species throughout its range. There have been substantial losses of chicks to Great White Pelicans (Pelecanus onocrotalus) and Kelp Gulls (Larus dominicanus) (e.g. Mwema et al. 2010, Voorbergen et al. 2012). Human disturbance to breeding colonies is still a serious threat on some islands in South Africa: Cape Cormorants are susceptible to abandon nests temporarily or permanently in the presence of humans (approaching within ~20 m of nests) and nest contents may then be swiftly predated by breeding Kelp Gulls (T. Cook, pers. comm.).
Conservation Actions Underway
Following past declines caused by guano mining, guano platforms have been constructed to increase the extent of suitable breeding grounds (del Hoyo et al. 1992). Strict measures were put in place on Dyer Island in 2004, to control an outbreak of avian cholera (Cape Times per R. Thomas in litt. 2004). A selective cull of Cape Fur Seals was instigated in 1993, with immediate but short-term effect on seabird mortality rates (David et al. 2003). Conservation Actions Proposed
Conduct simultaneous surveys at all colonies to obtain an up-to-date population estimate. Monitor population trends through regular surveys (Barnes 2000). Monitor trends in the stocks of prey species. Enforce measures to prevent and mitigate oil-spills. Develop emergency plans for the control of disease. Reduce commercial fishing of small pelagic fish (anchovy and sardine) off the South-West coast of South Africa.
|Amended reason:||Edited: Geographic Range, Population Justification, Habitats and Ecology, Threats, Conservation Actions proposed, Underway and in Place, Important Conservation Actions Needed, Research Needed and Generation Length. The estimated number of mature individuals were altered. Added references and also added a new Contributor and a new Compiler.|
|Citation:||BirdLife International. 2017. Phalacrocorax capensis. (amended version published in 2016) The IUCN Red List of Threatened Species 2017: e.T22696806A112389448.Downloaded on 29 June 2017.|