About one half of the total population, currently estimated at about 30 000 birds, are within the Greater Cape Town area.
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It breeds in large colonies, and the main traditional breeding colony for the Cape Town area is on Robben Island.
Kelp Gull | Pacific Gull | Gull | Yellow-legged Gull | Sooty Gull | gull | Black-billed Gull | Silver Gull | Red-billed Gull | Percival Gull | Mediterranean Gull | Grey Gull | Franklin's Gull | Caspian Gull | Western Gull | The ''Larus'' gulls interbreed in a ring around the arctic. 1: Lesser Black-backed Gull | Sir William Gull, 1st Baronet | Sabine's Gull | Olsenbanden tar gull | lesser black-backed gull | kelp gull | Heuglin's Gull | Heermann's Gull | Hartlaub | Gull-wing door | Gull Lake | Black-tailed Gull | Birula's Gull |
The name of this bird commemorates the British explorer Sir Edward Belcher.
The subspecies D. a. modestus (Príncipe) together with D. a. coracinus and D. a. atactus (Bioko and mainland west and central Africa from Guinea east to western Kenya and south to Angola) is usually split as a separate species, the Velvet-mantled Drongo D. modestus, (Hartlaub, 1849).
The nutrient-rich cold waters found in the basin are known to be especially favorable to phytoplankton and the numerous islands within it are important bird habitats, including Sabine's Gulls and many types of shorebirds.
Hartlaub's Duck is resident in equatorial West and Central Africa, from Guinea and Sierra Leone east through Nigeria to Sudan, and south to Gabon, Congo and Zaire.
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Analysis of mtDNA sequences of the cytochrome b and NADH dehydrogenase subunit 2 genes suggests that it belongs into a very distinct clade—possibly a subfamily of its own—together with the Blue-winged Goose, another African species of waterfowl with uncertain affinities.
Heermann's Gull (Larus heermanni), a gull resident in the United States, Mexico and extreme southwestern British Columbia
Many rare visitors have been seen over the years including Wilson's Phalarope, Western Sandpiper, Marsh Sandpiper, Franklin's Gull and Citrine Wagtail.
The municipal dock, located at the south end of the lake, is a regular meeting spot for bird watchers; who have caught sight of Franklin's Gull among other birds.
The introduction of the strong-growing smooth cordgrass (Spartina alterniflora) has also had deleterious effects.
Thayer's Gull (Larus thayeri) is a large gull native to North America that breeds in the Arctic islands of Canada and winters primarily on the Pacific coast, from southern Alaska to the Gulf of California, though there are also wintering populations on the Great Lakes and the upper Mississippi River.