Freckled Duck (Stictonetta naevosa) Fact Sheet: Physical Characteristics

Body measurements

Data sources:

• Frith (1967): weight, head–body length
• Norman (1982): average wing length (sample from Victoria)
• Marchant and Higgins (1990): wing span

Plumage

• Mostly dark gray-brown with small buff-to-whitish “freckles” on head and upperparts (Johnsgard 2010; Carboneras and Kirwan 2018, except as noted)
  • From a distance, appear almost black
  • Distinctive coppery sheen in flight (Pizzey and Knight 2012)
  • Underparts paler
    • White, triangular patch and whitish speckling (Pizzey and Knight 2012; Carboneras and Kirwan 2018)
  • Pattern of irregular lines on flanks and at base of tail (“vermiculation”)
  • Undertail buff to warm brown
• Male and female difficult to tell apart at a distance (Frith 1965)
  • Female’s plumage lighter and lower contrast compared to male (Frith 1965; Frith 1967; Carboneras and Kirwan 2018)
    • Freckles buff, not pure white
    • Head and neck coloration not as dark
• Juvenile (Frith 1967; Johnsgard 2010)
  • Resembles female, except more pale
  • Freckles fine and a deep buff color
• Molting
  • No eclipse plumage (Carboneras and Kirwan 2018)
  • Body feathers molted continuously (Marchant and Higgins 1990)
    • Peak in late summer and early winter
  • Wing feathers often molted late summer (after breeding) (Marchant and Higgins 1990)
    • May occur in spring in some individuals

Head and bill

• Head appears almost triangular in side profile due to slight crest (Johnsgard 2010)
  • Distinctive trait
• Eye
  • Iris brown (Carboneras and Kirwan 2018)
• Bill
  • Coloration
    • Dark gray, olive-gray, or light gray (Johnsgard 1965; Marchant and Higgins 1990; Johnsgard 2010; Carboneras and Kirwan 2018)
      • During breeding season, upper bill of male has bright red or orange-red base
        • During non-breeding season, fades to dull gray
  • Shape
    • Curved or “dished” appearance (Frith 1967)
      • High at base (Frith 1967)
      • Tip appears flattened (Johnsgard 2010)
        • Adaptation for filter-feeding
          • Also see Diet & Feeding
      • Large nail on tip (Johnsgard 2010)

Legs

• Coloration
  • Dull slate-gray (Carboneras and Kirwan 2018)

Size of head

• Longer in adult male (Carboneras and Kirwan 2018)

Coloration

• See General Appearance

Trachea (windpipe)

• Elongated in adult male (Frith 1967; Fitch 1999)
  • Forms coil outside sternum region
  • May amplify male’s vocalizations when visual communication is impeded (Fitch 1999)
    • At night
    • When line of sight blocked by tall, dense vegetation near nest
  • For early studies, see Campbell (1899) and Johnsgard (1961)
• Comparison to other birds
  • Elongated trachea present in at least six avian orders and 60 species (Fitch 1999)
  • Long, looped windpipes also found in some swans (e.g., Trumpeter Swan), cranes, and the Magpie Goose (Anseranas semipalmata) (Frith 1967; Gaunt et al. 1987; Fitch 1999)

Similar-looking ducks

(Carboneras and Kirwan 2018, except as noted)

• Pacific Black Duck, Anas superciliosa
• Hardhead, Aythya australis
• Blue-billed duck, Oxyura australis (Pizzey and Knight 2012)

Behavior

• Freckled Duck carries head low, except when alert or before takeoff (Johnsgard 1965)
• Also see Locomotion

Resources

• Fact sheet with illustrations (Game Management Authority of Victoria)
• Video (Game Management Authority of Victoria)
  • 5-minute video with description of Freckled Duck and comparisons to similar ducks

Top image: A female Freckled Duck.

Bottom image: A male Freckled Duck with red bill typical during breeding season.

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