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Rh Nesting of the Fulvous Tree Duck.

HILE the Fulvous Tree Duck (Dendrocygna fulva Gmel.) is well known to nearly, if not all, our leading authorities and has been made the subject of extended notes by some,–notably Baird, Brewer and Ridgway, very little has been known of its nesting habits. I have made a special study of our Duck family and have personally taken sets of eggs of eight species, but it was not until June of this year (1898) that I had the good fortune to discover the nest of D. fulva, and as is the rule with desirable oological finds, my "take" was quite unexpected.

Mr. Brewer states in his notes that this duck occasionally visits the Island of Trinidad (at intervals of several years) and while on the island raises its young, several broods sometimes being raised during a season, but he is apparently unable to definitely state whether the bird nests upon the ground or in hollow trees as does its black-breasted congener. Col. Grayson discovered this duck in the vicinity of Sonora, Mexico, where it was fairly abundant during the breeding season. He was informed by natives of its nesting in that locality though he omitted to state other than that "the birds were said to lay from 12 to 15 pure white eggs."

My impression is that this bird is among the most variable and cosmopolitan in its nesting habits of any of our ducks. While in the central part of the state during the early part of last June, I was collecting in an immense tule swamp containing a rookery of White-faced Glossy Ibis and Black-crowned Night Herons when I was surprised at seeing a large number of Fulvous Tree Ducks throughout the swamp. The birds were either in pairs or multiples of pairs, and although the sexes are usually so similar as to make identification at a little distance impossible, I could, on this occasion, readily locate the females by the fullness of the abdomen. The ducks were much interested in our movements, frequently circling around close to us and indicating their displeasure by continually uttering their peculiar whistle. As these actions were suggestive, my assistants and myself forsook the Ibis rookery and commenced a systematic search among the tules for possible nests of D. fulva. After a vain search of several hours we decided that it was either too early or else the birds where not nesting there.

June 25 found us again on the ground, the first pleasant observation being that instead of pairs, many single ducks (presumably old drakes) were scattered here and there; also that when a small group of birds were seen it was as likely to contain three or five ducks as two or four, all this indicating nests and setting birds—somewhere. We were not long in again penetrating the dense tules where we searched diligently for hours, but about the only nests found where dozens of the White-faced Glossy Ibis, which, at this time, nearly all contained four little jet black balls of down. Here I would mention the apparent apathy of the old Ibis' toward their young; the very instant we approached the nest the old bird would rise into the air and off she would go a mile or more to a feeding ground and frequently not appear while we were in the vicinity. A few weeks before, while collecting Ibis eggs, the parent birds continually hovered overhead or near-by and as soon as we were a few yards from a nest just robbed, the old bird would settle down on its edge and there remain in silence until lost to view among the thick rushes.

After a while I flushed a Redhead from her floating palace of dry tules and down, the nest containing 15 eggs which I soon discovered were not all alike. Twelve were undoubtedly those of the Redhead but three were different from anything I had ever seen and were slightly smaller, opaque, slightly pyriform and of a chalky appearance when compared with those of the Redhead. I instinctively decided that these three strange eggs were those of the Fulvous Tree Duck. Shortly after this