flying rapidly backwards and forwards close to the surface of the lake.
They kept their bills wide open, and the lower mandible half buried in
the water. Thus skimming the surface, they ploughed it in their
course: the water was quite smooth, and it formed a most curious
spectacle to behold a flock, each bird leaving its narrow wake on the
mirror-like surface. In their flight they frequently twist about with
extreme quickness, and dexterously manage with their projecting lower
mandible to plough up small fish, which are secured by the upper and
shorter half of their scissor-like
[picture]
bills. This fact I repeatedly saw, as, like swallows, they continued
to fly backwards and forwards close before me. Occasionally when
leaving the surface of the water their flight was wild, irregular, and
rapid; they then uttered loud harsh cries. When these birds are
fishing, the advantage of the long primary feathers of their wings, in
keeping them dry, is very evident. When thus employed, their forms
resemble the symbol by which many artists represent marine birds. Their
tails are much used in steering their irregular course.
These birds are common far inland along the course of the Rio Parana;
it is said that they remain here during the whole year, and breed in
the marshes. During the day they rest in flocks on the grassy plains
at some distance from the water. Being at anchor, as I have said, in
one of the deep creeks between the islands of the Parana, as the
evening drew to a close, one of these scissor-beaks suddenly appeared.
The water was quite still, and many little fish were rising. The bird
continued for a long time to skim the surface, flying in its wild and
irregular manner up and down the narrow canal, now dark with the
growing night and the shadows of the overhanging trees. At Monte
Video, I observed that some large flocks during the day remained on the
mud-banks at the head of the harbour, in the same manner as on the
grassy plains near the Parana; and every evening they took flight
seaward. From these facts I suspect that the Rhynchops generally
fishes by night, at which time many of the lower animals come most
abundantly to the surface. M. Lesson states that he has seen these
birds opening the shells of the mactrae buried in the sand-banks on the
coast of Chile: from their weak bills, with the lower mandible so much
projecting, their short legs and long wings, it is very improbable that
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