LIFE HISTORIES OF NOETH AMEBICAN DIVING BIEDS. 177 



When about 5 or 6 weeks old, long before they are grown or fully 

 fledged, they are able to take to the water and they often do so, either 

 accidentally or because forced off the ledges by their parents. Be- 

 cause of this habit the breeding rookeries are deserted by both old 

 and young birds much earlier than would be expected and long 

 before the other species that breed with them have left. During 

 the last week in July, 1916, I visited Bird Eock to study and collect 

 the young of the various species to be found breeding there, but was 

 disappointed to find that many, perhaps most, of the common murres 

 had left. There were quite a number of very small downy young 

 which were still unable to move about much and a few of the larger 

 young, about half grown and wearing their soft, juvenal plumage; 

 these half-grown birds were very lively and very noisy; evidently 

 they had about reached the stage where they are ready to leave and 

 probably many of them had already left. I estimated that there 

 were not over one-quarter as many murres on the rock as I saw on 

 my previous visit, but this apparently striking reduction in num- 

 bers was probably partially due to the fact that so many had already 

 left. 



Various writers have stated that the young birds are transported 

 to the water on the backs of their parents or that the old bird carries 

 the young one in its bill, seizing it by the neck or the wing. Both 

 of these methods seem improbable, and I can not find an authentic 

 account of anyone who has seen it done. Where it is possible to do 

 so, the young birds probably scramble or climb down to the water's 

 edge; but where they breed on steep cliffs overhanging the water, 

 the following method, described by Gatke (1895), is probably the 

 one usually employed ; he writes : 



In Heligoland this descent of the young birds from the cllflE to the sea Is 

 accomplished in the following manner : On very fine calm evenings at the end 

 of June or the beginning of July one may hear soon after sunset, from a dis- 

 tance of more than a mile, the confused noise of a thousand voices, the calls of 

 the parent birds, arr-r-r-r — orr-r-r-r — errr-r-r-r, and mingled with these the 

 countless tiny voices of their young offspring on the face of the clifE, 

 wrr-r-r4dci — irrr-r-r-idd, uttered in timid and anxious accents. The old birds 

 swim about quite close to the foot of the clifC, and the tone of their incessant 

 calls has in it something really persuasive and reasoning, as though they were 

 saying in their language, " Now, do come down, don't be afraid, it is not so hard 

 as it looks," whilst the little timorous voices from above seem to reply quite 

 distinctly, " I can not, I am so afraid, it is so dreadfully high." Nevertheless, 

 in its distress, the little chick tries to get as near as possible to the mother 

 waiting for it below, and keeps tripping about on the outermost ledge of rock, 

 often of no more than a finger's breadth, until it ends by slipping off, and, 

 turning two or three somersaults, lands with a faint splash on the surface of 

 the water; both parents at once take charge of it between them, and swim 

 off with it toward the open sea. 



