How they do it
is uncertain; it is probably in some such way as the night-hawk makes
his curious booming sound,--not by means of his open mouth, as is
generally supposed, but by slightly turning the wing quills so that
the air sets them vibrating. One can test this, if he will, by blowing
on any stiff feather.
On stormy days the birds, instead of resting on the shoals, light near
some lonely part of the beach and, after watching carefully for an
hour or two, to be sure that no danger is near, swim ashore and
collect in great bunches in some sheltered spot under a bank. It is
indeed a tempting sight to see perhaps a hundred of the splendid birds
gathered close together on the shore, the greater part with heads
tucked under their wings, fast asleep; but if you are to surprise
them, you must turn snake and crawl, and learn patience. Scattered
along the beach on either side are single birds or small bunches
evidently acting as sentinels. The crows and gulls are flying
continually along the tide line after food; and invariably as they
pass over one of these bunches of ducks they rise in the air to look
around over all the bank. You must be well hidden to escape those
bright eyes. The ducks understand crow and gull talk perfectly, and
trust largely to these friendly sentinels.
Pages:
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74