Magpie Goose (Anseranas semipalmata) Fact Sheet: Physical Characteristics

Body measurements

Data sources: Frith (1967), Carboneras and Kirwan (2017)

Note: Range for female wingspan slightly wider in Carboneras and Kirwan (2017) than Frith (1967).

Body

• Fairly large-bodied (Delacour 1954)

Plumage (coloration)

• Adult
  • Black and white (Frith and Davies 1961)
    • White mantle, rump, and underparts (Delacour 1954)
• Juvenile
  • More gray and mottled than adult (Carboneras and Kirwan 2017)

Wings

• Long and broad (Delacour 1954)

Head and neck

• Head protuberance of spongy bone (see image, right) (Whitehead 1998a)
  • Varies in size (Carboneras and Kirwan 2017)
• Bare skin between bill and eyes (Johnsgard 1961)
  • Coloration
    • Pink with irregular black speckles
• Bill
  • Hooked and robust (Frith 1967)
    • Adapted for digging corms (tuber-like storage organ in Eleocharis dulcis) out of soft mud and hard, semi-dried ground
  • Coloration (Delacour 1954)
    • Deep yellow
    • Gray tip
  • Texture
    • Has bumps; “pebbled” (Todd 1979)
• Neck
  • Long (Delacour 1954)
• Eye
  • Iris
    • Dark brown (Delacour 1954)
• Also see Trachea (windpipe)

Legs and feet

• Legs
  • Length
    • Long (Delacour 1954)
  • Coloration
    • Yellow-orange (Carboneras and Kirwan 2017)
• Feet
  • Characteristics
    • Partially webbed (Johnsgard 1961)
      • Webbing not well-developed, as in ducks, geese, and swans (Anatidae), and Whistling Ducks
        • A few geese also have reduced webbing
    • Long hind toe (Johnsgard 1961)
      • Unusual for waterfowl (Todd 1979)
  • Adaptive functions (Frith 1967)
    • Walking
      • On ground and over marsh vegetation
    • Perching
    • Nest building
  • Not adapted for swimming (Frith 1967)
• Claws
  • Strong (Frith and Davies 1961)

Tail

• Large (Delacour 1954)

Body mass

• Males about 30% heavier than females (Whitehead 1998a)

Plumage (coloration)

• No difference between sexes (Frith and Davies 1961; Whitehead 1998a)

Head protuberance

• Present in both sexes (Whitehead 1998a; Carboneras and Kirwan 2017)
  • Larger in adult male
    • May be a visual signal used during male-male competition or by females for mate choice

Trachea (windpipe)

• Structure is elongated and folded in males only (Frith and Davies 1961; Whitehead 1998a, except as noted)
  • Produces louder, deeper calls (Fitch 1999)
  • Length in adult male
    • About 127 cm (50 in) (Johnsgard 1961)
      • Maximum length: about 150 cm (59 in) (Johnsgard 1965)
  • Development
    • Male voice deepens after about eight months of age (Johnsgard 1961)
    • Elongation complete by two years of age
• Specific functions not well-understood (Fitch 1999)
  • Possible functions
    • Defense of territory
    • Group communication
    • Mate choice
    • Male-male contests
• Comparison to other birds
  • Elongated tracheas present in at least six avian orders and 60 species (Fitch 1999)
  • Some swans (e.g., Trumpeter Swan), cranes, and the Freckled Duck (Stictonetta naevosa) also have long, looped windpipes (Frith 1967; Gaunt et al. 1987; Fitch 1999)

Distinctive appearance

• Magpie Goose not confused for any other Australian bird (Frith 1967; Marchant and Higgins 1990)
  • From a far distance, recognizable by its slow flapping motion
• Differences of similar Australian birds
  • Straw-necked Ibis
    • Flaps wings more rapidly than Magpie Goose
    • Smaller than Magpie Goose
    • Long, decurved bill
  • Black swan
    • Flaps wings more slowly than Magpie Goose
    • Long neck
    • Body entirely black
    • Flight feathers white
      • Magpie Goose has black flight feathers

Molting

• Wing feather molt is gradual (Johnsgard 1961)
  • Still able to fly
• Also see “Juvenile” in Life Stages

Oil produced for preening

• Differs from that of other waterfowl (Edkins and Hansen 1972)
  • Composition
    • Squalene
    • Wax esters
    • Ducks, geese, and swans (Anserinae) produce fatty acids
  • Structure
    • Straight-chained
    • Multiple branches in ducks, geese, and swans

The characteristic head protuberance and robust bill of the Magpie Goose.

Magpie Geese use their bill to dig for food in mud and dry, hard ground.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.