Agelais tricolor Oct. 11 Harrell Ranch, 10mi. S Marysville, Yuba C., Caly. Tricolored blackbirds were here in flocks of thousands, birds very much in evidence in all the tule patches on the various duck ponds. We were in the vicinity of ponds 1-3. Breeding seems to be taking place in all these areas, perhaps less around 3 although I did not check carefully here. I went into the cat tails at the SW corner of pond 1, near the high levee. In about 15 feet the birds were spaced rather evenly on the tule, about 2-3 ft. apart. 15-20 feet in from the edge of the tule I began finding nests. In 2 separate trips into the same area (perhaps 10 ft. apart) I found 1 nest with 1 egg, 4 with 2 eggs, 6 with 3 and 4 with 4. There were some old nests and some new ones without eggs. Some of the unoccupied nests were not inside. Nests were from 1-6 feet above the water, which was about 3 feet deep. I got the impression that only nests 3-6 ft. high had eggs in them. Tules in this area were white with splashes of droppings from the perching birds. The birds arose in large flocks from the nesting areas, flying around the edge of the marsh. These flocks seldom flew out over dry land. Small flocks, up to a dozen, were often seen flying in to the marsh, but I saw few of these birds leaving. From the high levee at the outlet of the ponds (1) I could see marshy area on the other side, and there