Sunday’s Duck o’ the Week

It’s time for John Avise‘s weekly photographic effort to educate readers about the ducks of North America. Your job is to look at the photos and then guess the species. After you try, go below the fold for the ID and information.

We have a clue this week:

To help identify this week’s duck, readers should know that my pictures were all taken in Florida, where this species is a common year-round resident.







In flight:

Click on “read more” to see the ID, John’s Duck Facts, and a range map:

ID: Mottled Duck (Anas fulvigula)

This species is a close genetic relative of the Mallard (Anas platyrhynchos), but differs markedly from the latter in lacking strong sexual dimorphism; i.e., both sexes of the Mottled Duck look alike, and closely resemble Mallard hens.  [Thus, this situation provides a striking example of the evolutionary lability of sexual selection and sexual dimorphism].  The Mottled Duck resides in Florida and the adjoining Gulf Coast states, where it frequents shallow ponds and even puddles in roadside ditches.  Drakes have a bright yellow bill, the hen’s bill is more orange, and the blue speculum of both sexes is bordered front-and-back by black stripes, rather than by white stripes as in the Mallard.

A range map from the Cornell bird site:




  1. ThyroidPlanet
    Posted September 13, 2020 at 7:58 am | Permalink



    Honey is a conventional Mallard – not this one.

  2. ThyroidPlanet
    Posted September 13, 2020 at 9:03 am | Permalink

    Oh of course!

    Anas fulvigula – Mottled Duck

    Anas platyrhyncos – Mallard

  3. John Dentinger
    Posted September 13, 2020 at 9:29 am | Permalink

    I instantly said: Black Duck, Anas rubripes. Wrong. Sigh.

    • john avise
      Posted September 13, 2020 at 11:25 am | Permalink

      But the Black Duck was a very good guess (except for the indicated range) because the Black Duck is another close genetic relative of the Mallard; and, like the Mottled Duck, the Black Duck lacks strong sexual dimorphism.

  4. Posted September 13, 2020 at 10:30 am | Permalink

    Small range. Like Florida retirees.

    • Paul Techsupport
      Posted September 13, 2020 at 10:46 am | Permalink

      Hush your mouth! /grin

  5. Steve Gerrard
    Posted September 13, 2020 at 11:59 am | Permalink

    That extralimital range was drawn in with a Sharpie, wasn’t it.

  6. Posted September 13, 2020 at 12:03 pm | Permalink

    I am guessing that the ones with bright yellow bills are the drakes, like the mallard drakes.

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