THE OOLOGIST 



133 



away in broken squads toward all 

 points of the compass. Some of them 

 flew about high overhead as long as we 

 stayed in their part of the slough, but 

 the majority settled down in other parts 

 of the slough until we left, when they 

 again rose and came back. We found 

 the nests of the birds with sufficient 

 ease, for we had only to "follow our 

 noses" and we were sure to get there. 

 As we did not care for any sets we did 

 not stay long. We saw hundreds of 

 nests, most of them containing four 

 eggs, many two or three, four with five 

 and one with six. Here and there was 

 a nest containing young, but most of 

 the nests held fresh eggs. Later in the 

 season it is almost impossible to ap- 

 proach the place as the stench is nearly 

 suffocating, and always makes mo feel 

 ill. 



About ten o'clock the Franklin's 

 Gulls began to return from feeding and 

 we watched them circle overhead and 

 gradually settle in the south end of the 

 slough, so we started to wade down 

 that way. On the way down we saw a 

 Ruddy Duck, but could not find its nest. 

 On a ways farther a Red-head flushed 

 from a nest containing a single fresh 

 egg. Far out in the open water of the 

 center we saw what looked like a lot of 

 bogs — perhaps two dozen of them. We 

 had seen them before so we knew what 

 they were. For four years a colony of 

 American Eared Grebes have nested in 

 the same portion of the slough. We 

 went over towards them and as we got 

 nearer the male Grebes began to swim 

 and dive around us, watching us very 

 closely, but I could not hear them utter 

 a sound. As we got closer the females 

 began to slip off their nests until by the 

 time we got to them they had all left, 

 and males and f«^males had gone off to- 

 gether in a straggling flock and watched 

 us examine their nests. Most of the 

 nests were uncovered, but some of 

 those containing one or two eggs were 

 covered. I have read that Grebes do 



not incubate their eggs during the day 

 time, but cover them up and let the 

 warmth of the sun or of the decaying 

 vegetation of which the nests are made 

 incubat'^ the eggs during the hours of 

 daylight. This may be true in some 

 cases, but it is not a universal fact. 1 

 have never been able to surprise a Pied- 

 billed Grebe on her nest, but the Horned 

 and Eared Grebes I have frequently 

 seen sitting on their nests, and have ap- 

 proached within a few feet of the latter 

 before the? stepped off. The nests of 

 all the Grebes— at least all that breed 

 here— are alike in construction, a float- 

 ing bog of mud and dead vegetation, 

 loosely yet strongly piled together and 

 so constructed that the eggs may be 

 covered up in a moment's notice. Lo- 

 cation seems to be the only distinguish- 

 ing mark of the nests. The Pied-billed 

 nest singly in small ponds or along the 

 edges of larger sloughs; the Horned 

 Grebe ne.«*ts singly or in small colonies 

 aloug the edges of rush-bordered islands 

 in lakes or larger sloughs, while the 

 Eared nests in colonies of not less than 

 six or seven nests and frequently of 

 twenty-tive or thirtv, in open water in 

 the center of large rushy sloughs. The 

 eggs of the three species look very much 

 alike, bright chalky bluish when fresh 

 laid, gradually approaching deep olive 

 as incubation advances. The number 

 of eggs laid by the Eared Grebe is com- 

 monly given as four to eight, but four 

 is the almost universal number here. 

 Of twenty-nine-npsts examined this 

 spring none contained over four eggs. 

 Last year I found sets of five, and one 

 nest held eight eggs, but four were of 

 different shape than the others and I do 

 not think all eight were laid by the 

 same bird. 



As we waded along we accidentally 

 came upon a small colony of Forster's 

 Terns. There were six nests in a radius 

 of two rods, all containing three eggs 

 apiece. The eggs were indistinguish- 

 able in size and color from sets of Com- 



