In view of the paucity of information
on yawning in birds, commented on
by Sauer ans
Sauer, and of possible confusion with jaw
stretching, the following note may be of
interest. Some years ago I kepts a single, very
tame female Greenfinch, Carduelis chloris, in al
all-wire cage in a room.
One end of the cage was kept covered with
black cloth to exclude draft. At nights in
winter the temperature of the room sometimes
fell to the freezing point or below. One cold
night I entered the room, switched on the light
and looked into the cage, My head only a foot or
two from the sleeping bird. The bird woke,
stretched itself a little upright, and
yawned. During the latter part of the yawn I
was able to see, against the background of the
black cloth, a tiny cloud of condensation as the
bird exhaled. This would appaear to confirm that
exhalaison is associated with the yawning
movements in birds, and its seems probable that
inhalation occcurs during the earlier part of
the yawn.
The
Comfort Behaviour of Adélie and Other
Penguins
Ainley, David G.1
Comfort movements include the behaviours of
shaking, stretching, cleaning, preening, and
washing.
These were described and analyzed for
Adélie Penguins. The function for some
movements such as oil-preening was difficult to
determine and could only be hypothesized.
Cleaning, preening, washing, head-shaking, and
sneezing function in the care of body surfaces
and are responses to the presence of irritants
or foreign material on surfaces. Stretching and
other shaking movements may function to help
prepare muscles and peripheral circulation for
activity.
Ruffle-shakes may function to dissipate heat
and arrange plumage. Some movements of
oil-preening and some areas of the body preened
are performed in a predictable sequence ordered
according to functional relationships among the
different movements. Some movements are normally
performed only after certain others have been
performed.
Bathing in penguins is a socially
facillitated behaviour. The pattern of
Adélie bathing is determined largely as
an anti-predator strategy. Adélie,
African, and Humboldt Penguins perform the same
repertoire of comfort movements. The one
exception is that both spheniscids allopreen but
Adélies do not. The motor patterns of all
other movements except for two are the same for
the three species.
The two spheniscids perform the
jaw-stretch and the both-wings-stretch
differently than does the pygoscelid. The
comfort movement repertoires of several other
penguin species were compared to these. Their
repertoires were all very similar.
Head-shaking is performed in Adélies
during disturbance as a response to an increase
in secretion rate of the salt gland. The
increase in salt fluid secretion is probably a
result of a change in autonomic activity.
Head-shaking and social displays which
include a form of head-shaking have been
reported for several seabird species during
disturbance or social interaction. In
Adélie Penguins and albatrosses the
increased head-shaking during these
circumstances is a response to increased salt
gland secretion. It is hypothesized that some of
the head-shaking and head-shaking displays of
other seabirds are caused in the same way.
Head-shakes and other vigorous shakes and
stretch movements probably have signal
function during social interaction.
