Black Swan
Cygnus atratus (Latham, 1790)
Range: Australia
(Includes Tasmania)
Habitat: Lakes,
Rivers, Wetlands
Diet: Aquatic Plants,
Grasses, Insects
Social Grouping:
Pairs, Family Groups, Loose Colonies
Reproduction:
Monogamous (often for life), breed February through September; a nest of sticks and leaves is built on a floating mound in water; the 5-6 eggs are incubated for 35-48 days by both parents,
chicks fledge 150-170 days, are independent at 9 months, and sexually mature at 18-36
months; juveniles form their own flocks
Lifespan: 40 Years
Conservation Status:
IUCN Least Concern
- Body length 110-140 centimeters, wingspan 160-200 centimeters, weight 3.7-8.7 kilograms (males are slightly larger than females)
- Black plumage with some white wing feathers, a red bill, and red or pink irises; juveniles are gray-brown with lighter bills than the adults
- Black swans have the longest neck in relation to their body size of any swan species; the neck is often curved into “S” shape
- Birds molt after the breeding season and unable to fly for a month or so
- The least territorial of all swans, they sometimes form colonies
- Largely sedentary, they will become nomadic in times of food scarcity
- Adults have few predators, but eggs and fledglings can be taken by ravens, raptors, gulls, predatory marsupials, and rodents
- They have been introduced to Europe and North America; vagrants have been reported in Indonesia and New Guinea
- A subspecies (C. a. sumnerensisi) was hunted to extinction present in New Zealand; birds of Australian stock were then introduced to New Zealand and have become established
- Considered a crop pest in some areas, they hunted legally during a short annual season
- State bird of Western Australia, appearing on Coat of Arms and flag; important in aboriginal lore (in most versions, swans were originally people; in some versions they were originally white and were given black feathers by crows)
- Prior to 1697 discovery, “black swan” was European metaphor for something that couldn’t exist
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