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leaving what must look like snake-like traces in front of their main body impres-
sions.
Sunbathing accomplishes some of the same goals as dust baths but uses solar
power. When sunbathing, some birds simply lie down on the ground and soak up
rays, whereas others sit upright on branches or other perches. What they have in
commonisthatthebirdsspreadtheirwingsouttotheirsides.Why?WhenI'veseen
black vultures (
Coragyps atratus
) and turkey vultures (
Cathartes aura
) adopt this
posture on chilly winter mornings, I always assumed they did this to warm up. But
it may not be just the vultures that are getting warmed up but their parasites, which
start moving once they reach a certain temperature. This makes it easier, then, for a
bird to find and evict them.
Ornithologists have noted avian sunbathing since the 1950s, but paleontolo-
gistshaveseemedlessawareofhowthisbehaviormightconnecttonon-aviandino-
saurs. However, paleontologist Darren Naish, in a 2013 blog post, made such a link
byreviewingsunbathinginmodernbirdswhilealsoencouragingpeopletovisualize
andartisticallydepictsunbathingtheropods.Naish'spostwasaccompaniedbypho-
tographs of various species of birds—including an owl—lying on the ground with
wings spread out, basking in direct sunlight. Of these, the most striking photo from
an ichnological standpoint was of a secretary bird (which, incidentally, are wicked
predators) lying on its tummy and with its head up, wings out, and long tail feath-
ers behind it. Upon seeing this photo, I promptly imagined the bird disappearing,
leaving only impressions of its torso, wings, and tail feathers. I then wondered how
such a resting trace might act as a model for finding similar traces made by predat-
ory feathered theropods, whether in Jurassic or Cretaceous rocks. Trace fossils like
these would not only be very nice finds indeed, but also potentially interpretable as
something more than just “resting.”
Of course, many small songbirds bathe in what we regard as a conventional
way by using water. In such instances, the bodies of water used for bathing might
vary from puddles to ponds to lakes to oceans. Anyone who owns a birdbath or has
