American Black Duck ( Canard noir ) |
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Anas rubripes |
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General NotesAt one time, the American Black Duck was the most common and widely distributed duck in Ontario. In the last four or five decades, however, the eastern expansion of the Mallard has come at the expense of the Black Duck, especially further south. The major factor contributing to the decline seems to be hybridization with Mallards, though Mallards are also better competitors for the same types of preferred nesting habitat. In northern and eastern Ontario, Black Duck populations still seem to be faring very well compared to other parts of their range. The Black Duck is more susceptible to human disturbance than most other waterfowl. If disturbed before the clutch is complete, it will abandon the nest. Sensitivity to disturbance is thought to be a contributing factor to its decline. It feeds principally on pond weeds and aquatic invertebrates. The Black Duck seems particularly susceptible to lead poisoning. The shot pellets that it picks up from the bottom of the marsh effectively paralyze the stomach muscles. Non-lethal effects include reduced growth rates, increased susceptibility to predation and disease, and reduced clutch sizes. |
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| Abundance: | Common | Earliest observed date: |
Typical arrival date: |
April 7 | |
| Breeding Status: | Breeding | Latest observed date: |
Typical departure date: |
November 7 |