LIFE HISTORIES.OF NORTH AMERICAN DIVING BIRDS. 17 
the horse gutteral creaks and grunts of the coots, with many varia- 
tions, furnished the necessary accompaniment to the chorus. But 
the real striking features of the concert, the solo parts, were the 
weird cries of the Holbeell’s grebes, heard only at infrequent inter- 
vals. The performance begins with a series of loonlike wailing 
cries, loud and piercing at first, and then runs off into a series of 
short, plaintive, vibrating wails, “ah-oo0, ah-oo0, ah-ooo, ah-ah-ah- 
ah-ah;” sometimes it ends in a more staccato, chattering trill and 
might be indicated thus: “whaaa, whaaa, whaaa, whaaa, whaaa, 
chitier-r-r-r-r-r-r.” There is considerable variation in the length 
and form of the song in different individuals. The love song of the 
Holbeell’s grebe may be heard at any time during the day or night.” 
but it is indulged in more freely in the early morning and toward 
the dusk of evening. 
Mrs. Lizzie T. Burt described the notes of an adult bird, which 
was captured on the ice near my home on February 14, 1918, as loud 
trumpetings, suggesting the cries of the loon and resembling the 
sound made by what is known as a Gabriel’s horn on an automobile. 
This grebe has several other notes, one of which is aptly described by 
Mr. Silloway (1902), as follows: 
It is a coarse, prolonged nasal quonk, the nasal quality being most pro 
nounced, the intonation being very suggestive of the braying of a donkey. 
Indeed, the natives call this grebe the ‘“ jack driver,” and anyone famfliar 
with the nasal volume of tone produced by C. holboelli will readily admit the 
appropriateness of the popular name. : 
Mr. W. L. Dawson (1909) refers to its notes as follows: 
Owing to the furtive habits of the various swamp dwellers, it is often diffi- 
cult to distinguish notes, but I have attributed a harshly raucous cawack, 
awwack caawwrrack heard in June upon the Pend d’Oreille River to this 
species. It is generally similar to the yark of the horned grebe but has several 
times the volume. 
Mr. Allan Brooks (1903) says that in British Columbia, where 
both species are abundant, the Holbeell’s grebe “wages incessant 
war upon” the horned grebe, “the large birds diving and coming 
up beneath the smaller ones time and again to the terror of the poor 
little fellows, who often desert their nests in consequence.” It must 
be a formidable foe with such a sharp and powerful beak. When 
once it has passed the downy young stage it must be well able to 
defend itself and escape from its enemies. 
Fall.—During the migrations I have always found this grebe to 
be a solitary species, but, according to others, it seems to be more 
or less gregarious at times. Mr. John Macoun (1909) speaks of 
“large flocks seen on Prince Edward Island, August 7, 1888.” On 
the Pacific coast it more often congregates in flocks on the migra- 
tions and during the winter, though I doubt if it actually flies in 
