LIFE HISTORIES OF NORTH AMERICAN DIVING BIRDS. 139 
birds, swimming in a straight line, one ahead of another. They 
seldom attempted to escape by flying, but preferred to swim away, 
making very good speed with little apparent effort or with very little 
disturbance of the smooth water; if too hard pressed they dove 
quickly, one at a time, or occasionally all together; they did not 
remain under water very long or swim very far away, appearing sud- 
denly on the surface at no great distance without causing a ripple. 
The dive is made with a forward semicircular plunge; the bird often 
leaves the water entirely, sometimes leaping above the surface as 
much as 6 inches, and plunges down into the water head first, making 
a clean, smooth dive. While swimming under water it uses its wings 
freely. Mr. Swarth (1911) noted this habit and recorded his observa- 
tion as follows: 
On June 7, while we were passing through numerous large flocks, the sea 
was unusually clear and smooth, and by standing in the bow of the launch, 
I had frequent opportunity to observe how the murrelets used their wings 
under the water. When diving they make a sudden flirt of the wings that can 
be seen at quite a distance, but it was not until several individuals had passed 
close under the boat that I could see, as was plainly apparent, that they had 
used their wings continually. They were literally flying under the water, but 
the manus was held about parallel with the body,-and not outstretched, as 
when going through the air. 
Where these murrelets breed in large numbers they are severely 
persecuted by the natives who visit the breeding colonies regularly 
to gather eggs or to kill the birds for food, for both are excellent 
eating and much in demand. Fortunately much of the region where 
they breed, particularly in the Aleutian Islands, is uninhabited. The 
Peale’s falcon seems to be one of their worst enemies. Mr. Little- 
john gives the following interesting account of its hunting methods: 
Great numbers of these birds are taken by Peale’s falcon, who seem to be 
one of their principal enemies next to man. As I have already stated, the 
murrelets are mainly found at some distance from land during the day, and 
here, too, this falcon pursues them, watching for a chance to seize any mur- 
relet he succeeds in driving from the water. After having secured its prey, 
the falcon circles about for a short time and then partakes of its meal. To 
do this he hovers, remaining almost stationary for several minutes at the 
time; in the meantime the prey is raised well up to the beak with both feet, 
and promptly devoured. When the murrlets return to the land at nightfall, 
the falcon is there also to meet them, and soon again secures his nightly repast. 
The only note which I have ever heard’from this species is a shrill, 
faint, whistling call note. Mr. Littlejohn describes their call note 
on the breeding grounds as “a very low but rather shrill whistle,” 
and he says that “while out at sea, the ancient murrelet utters a 
peculiar piping whistle, entirely different from the one uttered while 
on the nest.” Mr. E. W. Nelson (1887) says “They were in pairs, 
and not shy. When one was shot the survivor would fly about in 
