Read the passage.

to waken an old lady

by william carlos williams

old age is
a flight of small
cheeping birds
skimming
bare trees
above a snow glaze.
gaining and failing
they are buffeted
by a dark wind—
but what?
on harsh weedstalks
the flock has rested,
the snow
is covered with broken
seedhusks
and the wind tempered
by a shrill
piping of plenty.

what do the small cheeping birds symbolize in this poem?