Bulletin 3 - Peabody Museum of Natural History - Yale University

More documents

Recommendations

Info

HYBRID MALLARD (Anas platyrhynchos)DUCK (Anas rubripes)X BLACK(PI. Ill, Fig. 19)THIS bird (Peabody Museum, Yale University, Cat. No.11035) was taken with two wild red-legged black ducks atMilford, Connecticut, November 11, 1932. It resembles A.rubripes rubripes closely on head and neck. The upper andunder parts of the body are somewhat lighter and warmer incolor. Feathers of the breast and under tail coverts especiallyare widely margined with vinaceous-cinnamon (IV/15). Many ofthem have one or more additional interrupted bars of the samecolor. This reddish tendency is doubtless inherited from themallard.Even more mallard-like are the wings. Although in hue thespeculum is greenish-blue, as in the black duck, it is bordered bythe two white bars of the mallard, one crossing the greatercoverts below their black tips and the other whitening the ends ofthe secondaries. The white under wing coverts show theirrubripes inheritance in the broken row of dark spots near theedge of the wing. Like both mallard and black duck, this hybridhas white axillars, but is exceptional in bearing one right axillarwith three broad, but incomplete bars and a terminal spot of gray.When first seen the tarsi were lighter colored than in the blackduck, and less orange than in the mallard; according to Ridgway'snomenclature (1896) the hue was two-thirds salmon (PlateVII, No. 17) and one-third saturn red (VII, 16) ; feet somewhatmore dilute. Tarsi of a black duck taken at the same timewere two-thirds salmon and one-third orange vermilion (VII, 12).In form the only notable hybrid character is in the bill. Thisis intermediate between the higher, wider, parallel-sided beak ofA. rubripes and that of A. platyrhynchos which is narrower atthe base and somewhat flatter anteriorly. When fresh the colorwas chromium green (X, 12) warmed with olive-yellow (VI, 16)
24 PEABODY MUSEUM OF NATURAL HISTORYtoward the base, and fading through sage green (X, 15) to peagreen (X, 9) at the tip; darker along antero-lateral edge; nailnearly black; upper surface of culmen dusky. The bill ofA. rubripes taken at the same time was nearly ochre yellow(V, 9), with nail and margin darker; much darker on inside ofupper mandible and on teeth of lower mandible.There can be no possibility that this bird is an immature malemallard, for the head and neck are typically ashy as in the blackduck, not buffy. The tail feathers lack the white margins of themallard and are in prime condition instead of being ragged andworn as is usually true of the immature mallard in November.The breast is very much darker than that of a young mallard.
Page 2 and 3: PEABODY MUSEUM OF NATURAL HISTORYTR
Page 4 and 5: HYBRID DUCKS, INCLUDINGDESCRIPTIONS
Page 6 and 7: HYBRIDS OF THE GOLDEN-EYE (Bucephal
Page 8 and 9: HYBRIDS OF THE MERGANSER (Lophodyte
Page 10 and 11: HYBRID DUCKSTABLE ICOMPARISON OF NE
Page 12 and 13: HYBRID DUCKS 11Lophodytescucullatus
Page 14 and 15: HYBRID DUCKS 13Reference to the tab
Page 16 and 17: PLATE IFig. 1. Hooded merganser (Lo
Page 18 and 19: PLATE 11a a b c10*r*~•J!-.: t*.;,
Page 20 and 21: HYBRID DUCKS 15Brunswick (probably
Page 22 and 23: HYBRID DUCKS 17is assumed. In this
Page 24 and 25: HYBRID DUCKS 19About 26 serrations
Page 26 and 27: Like LophodytesNew Haven ..Blending
Page 30 and 31: BENT, A. C.BIBLIOGRAPHYLife histori
Page 32: Additional Copiesof this Bulletin m

Bulletin 3 - Peabody Museum of Natural History - Yale University

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?