Sept., 1914 NOTES ON A COLONY O1 ? TKI-COLOKED KEDWlNGS 2O5 this year, with better opportunities for observation, that it seems pardonable to touch upon the subject once more. The nesting ground before described (ConDoR n, November, 190.0, page 122) was a remarkably crowded one. In a patch of tules of very limited extent beside a flowing well, the birds had built their nests in such numbers that many were abandoned when other nests were built above them, and the tules grew so high and thick as to make the lower tiers dark, dirty and inaccessible. The colony breeding this year on the Rancho Dos Rios, Stanislaus County, California, was a much larger one than the above, but the breeding ground was acres instead of yards in extent. While there must have been several thousand birds in it there was plenty of room and no great crowding together of nests, though even with so much space there were many nests only a few feet, and in some instances only a few inches, apart. None, however, were built over others, notwithstanding the different heights above the water, vary- ing from six inches to about three feet, the water 'itself being about knee deep. While the writer first noticed signs of building on April 14, 1914, it prob- ably commenced shortly before that date, as the spot had not been visited for several days previously. On that day birds were noticed carrying building material, and upon further investigation a few beginnings of nests were found. As only a comparatively sin.all portion of the tule patch was explored it is very possible that there were some nests not seen on that day that were farther advanced in construction. The colony was visited next on April 23 on which date some nests were found to contain their full complement of four eggs, some two or three, and' others still empty but apparently ready for occupancy, the majority being those with two or three eggs. A few sets were selected from the vast num- ber on this day and the next, and the eggs were found to be from fresh to slightly incubated, with one or two sets about one-third along. Another visit was made on April 29, when most of the nests seen on the 23rd and 24th, along the paths made by forcing my way through the tules on that occasion, contained four eggs, although a few held only two or three, and some were still empty. A small number had hatched out Within the last few hours, but nests containing young were scarce. There appeared to be birds yet building and a few sets seemed to be fresh. Among those nests in which incubation was completed the greater number contained from two to four young, yet a few held only one. Many nests were very poorly constructed, and were falling down on one side; so much so, in fact, that the eggs had evi- dently rolled out. In one such case a poor youngster, just hatched out, was the only occupant, and he was hanging on for dear life with tooth and toe-nail at the very lowest edge. Rapid growth of the tules may have had something to do with the condition of some of these nests, but there evidently was a great difference either in architectural ability or constructive energy among the members of the colony. In the deseription of the l?Iadera County breeding ground stress was laid on the fact of so many nests having been abandoned, while in this colony but few were deserted, and those possibly by the acaidental death of the builders, and but few were robbed by hawks. It seemed, however, as if the birds must have stolen nests from each other'; as, for instance, in the case of one set that was blown and found to be composed of three very fresh eggs and one ex- tremely rotten one! And in another where one holding the full complement of four was found to be built over a nest already containing four eggs, rotten,
