Anyone who has every watched a furry feline relaxing by a fireplace
knows the restorative powers of a catnap. But a "birdnap?"
sleep loss and its effect on migratory birds, scientists at The
University of Southern Mississippi are hoping to answer some questions
about how these weary travelers cope without rest. In turn, the
findings could prove useful for the millions of Americans who suffer
from sleep disorders and sleep-deprivation.
are active during the day but migrate at night. Dr. Frank Moore,
chair of the biology department at Southern Miss, says birds may
make up for lost sleep at night by taking short naps - even perhaps
while on long, migratory flights. This phenomenon - called "unihemispheric
sleep" - occurs when one half of the bird's brain sleeps while
the other remains active.
birds are naturally sleep-deprived by the nature of their migratory
habits, they may provide some insight in how animals, including
humans, compensate for sleep loss," said Moore, whose research
was funded by a grant from the National Science Foundation and was
recently featured on National Geographic Magazine's Web site.
that lose sleep or don't compensate for losing it may suffer in
their ability to find food or avoid predators," Moore added.
"It's not unlike how our performance suffers when we go without
sleep for long periods."
Verner Bingam, a behavioral neuroscientist at Bowling Green, Moore
is concentrating on one species of bird, called Swainson's thrush.
Working with the species both in the lab and in the field, the researchers
are able study the birds' behavior and electronically measure patterns
of brain activity.
and his colleagues ultimately discover could shed light on human
sleep as well, according to Dr. John Harsh, director of the Southern
Miss Psychology Department's Sleep Laboratory.
know from our personal experiences that loss of sleep results in
sleepiness and a reduced ability to be productive and stay out of
harm's way when we are awake," Harsh said. "Saying that
we sleep to avoid sleepiness is, however, no more meaningful than
saying we eat to avoid hunger."
scientists still do not know the function of sleep and any new findings
are of great interest. "That's why Dr. Moore's research is
so important," Harsh added.
Like most bird
species, Swainson's Thrush are active during the day and sleep at
night, except during migration. Since these nighttime flights disrupt
their normal sleeping patterns, the birds must make up for it somewhere,
and Moore's research aims to uncover how.
birds might devote more time to sleep during the day, and brief
periods of sleep have been observed during the late afternoon just
prior to the onset of nightly migratory restlessness," Moore
during the day could come at a cost, Moore said, because that is
when birds forage for food. This can have serious consequences for
a bird's health if, stressed from a long migratory flight, the bird
puts its sleep needs before its caloric needs.
One way Moore
suggests birds mitigate the conflict between sleep and wakefulness
is by engaging in unihemispheric sleep, which is known to exist
in some marine mammals.
This is where
the similarities between humans and birds diverge. Harsh said, "There
is a shared need for sleep, and sleep and wake states generally
appear to be regulated by similar mechanisms."
sleep of migrating birds is "dramatically changed" and
in ways that we do not understand, Harsh said.
that leads to understanding these changes is likely to bring us
closer to an appreciation of the function of sleep and to a greater
ability to treat the many disorders of sleep."