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 May, 19or I I:volfition i# the Breeding HabRs of fhe Fulvous Tree Duck. THE CONDOR 6 7 'OR the preparation of this article I am iudebted to Mr. H. Wan- zer, chief engiueer for Miller & Lux, and C. W.P. Smith, a local collector of some note, both of Los Banos, for my in- formation on the breeding habits of this species from its first appearance in Merced county, until last season when I spent three months collecting in that lo- cality. Mr. Wanzerstates that Dendrocyna fulva was first brought to his notice in June 895, and that they have returned each subsequent season, arriving about the first of June, and that they did not seem to increase until about x898, but since that time have increased with such rapidity that they now are com- mon summer residents in the irrigated districts around Los Banos. From time to time since x895 pot- hunters have told wonderful stories of finding large numbers of eggs piled up ou bunches of dead grass and on small knolls that rose above the water in the swamps. The number of eggs in these nests ranged from 30 to xoo or more, ac- cording to report, and in not a few cases the finder has brought the eggs with him in order to prove that what he said was true. About the I5th of June x896, Mr. Wanzer found a nest, if such .it would be called, in Camp 3 swamp, contain- ing 62 eggs. The eggs were placed on a pile of dead grass which had drifted together about four inches above the water, and looked as if someone had emptied them carefully out of a basket, there t)eing no attempt at nest-building or concealment. Mr. Wanzer took twelve eggs, three of which are now in the collection of W. H. Hayes of Los Banos, and the other nine he placed under a hen, five of them hatching. He states that the young were black with a white band around the neck. A pen was built for the purpose of watch- lngthem mature, but they all died within a week. I saw quite a number of the young last season but failed to observe the white band of which Mr. Wanzer speaks. The young are very difficult to get as they always make for the tall grass at the edge of the water at the slightest noise. Those that I procured were partly feathered and probably too old to show auy indica- tion of the white about the neck. I found from inquiry among local col- lectors and hunters that no one is posi- tive of seeing auy young of this species until the last two or three seasons, and I was unable to find anyone who had found one of these large clutches last season. Most of the huuters agree that the large clutches are becoming very rare, which goes to show that instead of colonizing and laying from 3 to ioo eggs in a set without any attempt at nest-building and just out of the water on floating vegetation similar to the coots, they are becoming civilized and are nesting sinfilarly to other species of ducks. There may be a few silurians that still persist in colonizing, but if so, they fai16d to come under my uotice last sea- son. While I have heard a great deal about the eggs beiug incubated by the heat generated from decaying vegeta- tion, I have been unable to find anyone who is positive of any of these large dutches being incubated by this pro- cess, so I think I can safely say that it is a mistaken idea with regard to the Fulvous Tree Duck, from the fact that there is no authentic data of anyone seeing young of this species until the past few years. Also there was no per- ceptible increase in numbers until they had quit colonizing. I collected five sets of eggs of this species last season and in every in- stance the nest was placed on dry ground and so well concealed that it would be very hard to find withottt flushing the old bird. I found this duck not a very dose setter, it gener- ally flying when I was 2o or 25 feet 'from the nest. I took my first set on