EN
Cape Gannet Morus capensis



Taxonomy

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: #http://www.aerc.eu/DOCS/Bird_taxa_of _the_WP15.xls#.
Christidis, L. and Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Australia.
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.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: #http://www.museum.lsu.edu/~Remsen/SACCBaseline.htm#.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- A2acde+3cde+4acde A2acde+3cde+4acde; B2ab(iii,v)

Red List history
Year Category Criteria
2018 Endangered A2acde+3cde+4acde
2017 Endangered A2acde+3cde+4acde
2016 Vulnerable A2acde+3cde+4acde; B2ab(iii,iv,v)
2012 Vulnerable A2acde+3cde+4acde; B2ab(iii,iv,v)
2008 Vulnerable A2a,c,d,e; A3c,d,e; A4a,c,d,e; B2a+b(iii,iv,v)
2007 Vulnerable
2004 Vulnerable
2000 Vulnerable
1994 Lower Risk/Near Threatened
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type Land-mass type - shelf island
Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 326,000 medium
Extent of Occurrence non-breeding (km2) 12,000,000 medium
Extent of Occurrence breeding/resident (km2) 440 medium
Number of locations 6 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 246000 good estimated 2010
Population trend Decreasing good estimated -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 50-79 - - -
Decline (10 years/3 generation past and future) 50-79 - - -
Number of subpopulations 1 - - -
Largest subpopulations 100 - - -
Generation length (yrs) 20.2 - - -

Population justification: The most recent population estimate is made up of 10,500 pairs at Ichaboae Island, 2,200 pairs on Mercury Island and 380 pairs on Possession Island, all in 2010 (Kemper 2015). 81,000 pairs were estimated at Bird Island (Algoa Bay), 21,000 pairs at Malgas Island and 8,000 pairs at Bird Island (Lambert’s Bay) in 2015 (Crawford et al. 2015 updated by R. Crawford in litt. 2016). This gives a global total of 123,080 pairs, which equates to 246,160 mature individuals, rounded here to 246,000.

Trend justification: The total breeding population was previously estimated to have declined by 1.14% per year over the 49 years between 1956-1957 and 2005-2006 (Kemper et al. 2007). Recent data, however, shows that the species may in fact be declining at a faster rate than this. Historically, the global population numbered c.254,000 breeding pairs in 1956, but has subsequently decreased to c.249,000 pairs in 1968, c.179,000 in 1989 and c.145,000 pairs in 2005 (Crawford et al. 2007). The most recent population estimate is made up of 10,500 pairs at Ichaboae Island, 2,200 pairs on Mercury Island and 380 pairs on Possession Island (Kemper 2015), with 81,000 pairs at Bird Island (Algoa Bay), 21,000 pairs at Malgas Island and 8,000 pairs at Bird Island (Lambert’s Bay) (Crawford et al. 2015 updated by R. Crawford in litt. 2016), which gives a global total of 123,080 pairs. This gives an overall decline of 51.5% between 1956 and 2015, and with only minor extrapolation this would equate to a c.52.4% decline over 3 generations (60.6 years). An analysis that used a Bayesian state-space model to nests counts made between 1956 and 2016 at the species’s six breeding colonies indicated a decline of 51.5% (95% credible intervals: 39.5–62.5%) over three generations. Overall, 61.6% of model iterations fell within the 50–79% decline band and 38.3% fell within the 30–49% band (R. Sherley in litt. 2017). When comparing the most recent population estimate to the 1968, 1989 and 2005 estimates and projecting these rates of decline into the future, the rate of decline over three generations would be c.60%. Therefore, rates of decline over three generations likely fall within the range of 50-79%.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Angola N Extant Yes
Brazil V Presence Uncertain Yes
Cameroon N Presence Uncertain Yes
Congo N Presence Uncertain Yes
Congo, The Democratic Republic of the N Presence Uncertain Yes
Equatorial Guinea N Presence Uncertain Yes
Gabon N Presence Uncertain Yes
Mozambique N Extant Yes
Namibia N Extant Yes
Nigeria N Presence Uncertain Yes
São Tomé e Príncipe N Presence Uncertain
South Africa N Extant Yes
Togo N Presence Uncertain

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Angola Iona National Park
Angola Mussulo
Angola Quiçama
Mozambique Pomene
Namibia Mercury Island
Namibia Ichaboe Island
Namibia Possession Island
South Africa Algoa Bay Islands: Addo Elephant National Park
South Africa Bird Island
South Africa West Coast National Park and Saldanha Bay islands
South Africa Alexandria coastal belt / Algoa Bay Island Nature Reserve - Marine
South Africa Bird Island / Dassen Island / Heuningnes river and estuary system / Lower Berg river wetlands - Marine
Namibia Sperrgebiet - Marine

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Coastal/Supratidal Sea Cliffs and Rocky Offshore Islands major resident
Marine Neritic Pelagic major resident
Marine Oceanic Epipelagic (0-200m) major resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Fishing & harvesting aquatic resources - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Indirect ecosystem effects, Species mortality
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species mortality
Climate change & severe weather Storms & flooding Timing Scope Severity Impact
Ongoing Whole (>90%) Negligible declines Medium Impact: 6
Stresses
Ecosystem degradation, Reduced reproductive success
Energy production & mining Mining & quarrying Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation, Ecosystem conversion
Human intrusions & disturbance Work & other activities Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Reduced reproductive success
Invasive and other problematic species, genes & diseases Problematic native species/diseases Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition
Pollution Industrial & military effluents - Oil spills Timing Scope Severity Impact
Past, Likely to Return Majority (50-90%) Rapid Declines Past Impact
Stresses
Species mortality

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Food - human - - Non-trivial Recent
Pets/display animals, horticulture - - International Non-trivial Recent

Recommended citation
BirdLife International (2020) Species factsheet: Morus capensis. Downloaded from http://www.birdlife.org on 19/09/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 19/09/2020.