Image from the Biodiversity Heritage Library.
Contributed by Museum of Vertebrate Zoology, University of California, Berkeley.
| www.biodiversitylibrary.org
Transcription
Holmes, R.
1962
Erolia alpina
1 June BARROW, ALASKA
Elm wagon bluff - between Wibblocloz & Elegib
Sloughs: I bird as it became aware of my
presence stood upright (upright posture) - ran to
a nearly mound + again took this posture. The
fler up - aerial display + part tree +
[illegible] landed with b driving over head.
[illegible]
landed starfledig RB's (Hush 16 nearby) - plan drill
as it landed - I kept wing up + continued to
give the thrill
In aerial display- The wings may
be held in several positions:
(a)
(b)
(c)
The latter (c)
is the most frequent + is the posture in
which the wings are vibrated rapidly + or
kraa, kreea cue is given. When the bird is
going to descend, the wings are set at
and the bird glides or swoops
to the ground. The wings are usually held
at this angle (perhaps even higher) for about 1-2 seconds. They
are folded in place + the bird
begins to feed.
Flocks to three flocks (6, 8, 12 birds)
[illegible] thrace today + a number
(4-5) displaying birds which were