Family ANATIDAE Leach, 1820
Introduction
Anatidae (true ducks, geese and swans) has been recognised as a full family [Callaghan, D. & Harshman, J. (2005), Christidis and Boles (2008)]. DNA analysis, osteology and interpretation of the family by several writers (e.g. Johnson & Sorenson (1998, 1999) and Livezey (1991) has confirmed the position of the family as part of the cosmopolitan Order Anseriformes. Worldwide there are 146 species in 45 genera; 27 of which are Australian represented here by 28 subspecies. Hybridization between several of the species has been recorded.
Ducks and geese are more often seen in pairs to small flocks but some show gregarious tendencies forming large flocks during winter or in dry periods when water is scarce. Their calls are generally restricted to communication between pairs but in flight several utter loud calls. All inhabit wetland habitats, although some, such as the Pacific Black Duck and Australian Wood Duck are frequently seen in urban parks and gardens. All are herbivorous, many also feeding on small marine invertebrates.
Breeding behaviour in the family is complex; it usually follows the onset of wet seasons or after abnormal rains. Pairs are maintained as succinct pairings, females construct the nest of grasses in addition to adding fine down from their own breasts in situations such as under grass or reed tussocks or tree hollows. Incubation is undertaken by the both sexes. The eggs, numbering up to 12 in a clutch, have an elliptical shape with a slightly oiled appearance; the base colour varies between a pale blue-green, creamy white to white and are generally unmarked apart from staining through sitting on decaying nesting materials. The young are precocial and able to leave the nest shortly after hatching. Assistance to leave is often supplied by the parent carrying or pushing the young from tree hollows. They are attended to by the adult for the first few weeks after hatching but quickly become independent.
General References
Callaghan, D. & Harshman, J. 2005. Chapter 2. Taxonomy and systematics. 14-26 pp. in Kear, J. (ed.). Ducks, Geese and Swans. Oxford : Oxford University Press 1, 908 pp.
Christidis, L. & Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. Melbourne : CSIRO Publishing 288 pp. [62]
Johnson, K.P. & Sorenson, M.D. 1998. Comparing molecular evolution in two mitochondrial protein coding genes (cytochrome b and ND2) in the dabbling ducks (tribe: Anatini). Molecular Phylogenetics and Evolution 10: 82-94
Johnson, K.P. & Sorenson, M.D. 1999. Phylogeny and biogeography of dabbling ducks (genus: Anas): a comparison of molecular and morphological evidence. Auk 116: 792-805
Livezey, B.C. 1991. A phylogenetic analysis and classification of Recent dabbling ducks (tribe Anatini) based on comparative morphology. Auk 108: 471-507