All images on this page are of a probable mallard/Canada goose hybrid (Anas platyrhynchos × Branta canadensis) photographed in Branch Brook Park, Newark, New Jersey on July 21, 2016 (specifically between Bloomfield Ave. and Park Ave.). The photos were taken by local resident Josephine Ireri and communicated by her husband Eric Martindale. They are used here with permission. Thanks! These images are of especial interest, because they seem to be the only photos available of such a hybrid.
Eric made the following comments about this unusual creature:
The parental birds in this cross come into potential breeding contact in both North America and Europe. Such hybrids have been only very rarely reported. Indeed, till now, this cross seems to have been reported just once, by ornithologist C. L. Sibley (1938), who does list it. Usually reports of hybrids that have not been corroborated by independent authorities are rather unreliable, but Sibley says (p. 329) that he confines himself to records of hybrids “about whose authenticity there can be no doubt.”
An objection: One person with extensive knowledge of observed variation in ducks asserted that this bird was no hybrid, but rather that it fell within the range of variation seen in domestic ducks. However, the mallard, Anas platyrhynchos has interbred with many different kinds of birds, and the resulting hybrids are often capable of producing offspring. And the mallard is widely considered as conspecific with the domestic duck. Surely, then, given legendary propensity of mallards to hybridize with nearly every type of waterfowl known, at least some of the variation seen in mallards and domestic ducks can be attributed to that hybridization. Therefore, any domestic duck having Canada goose traits should be suspected of having Canada goose ancestry, especially when it is observed, as in present this case, consorting with Canada geese.
This is an intersubfamilial cross (Anatinae × Anserinae).
Work cited: Sibley, C. L. 1938. Hybrids of and with North American Anatidae. IXe Congrès Ornithologique international (Rouen), pp. 327-335.
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