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STUDY SHOWS CONTROLLED FIRES CAN AFFECT SONGBIRD POPULATIONS
AUBURN, Ala.__--Musical training is not typically part of a wildlife
researcher's educational background but, when scientists began investigating
the effects of controlled burning of woodlands on wildlife populations,
an ear for music proved to be valuable.
Lee Stribling, a wildlife researcher conducting studies through the
Alabama Agricultural Experiment Station at Auburn University, began
a project in 1986 to evaluate the effects of controlled burning (known
as prescribed burning) on various types of wildlife. Included in that
study were turkeys, rabbits, quail, small mammals, amphibians and songbirds.
Prescribed burning is a common forestry management practice where a
controlled fire is used to burn away heavy underbrush in woodlands.
The fire allows for new plant growth and also opens areas for wildlife
feeding.
"For example, prescribed fires expose more of the seeds on the
ground and more insects," explained Stribling, a professor of zoology
and wildlife science at Auburn. "You also can stimulate production
by the plants using this technique."
The study, conducted at the Piedmont Substation in Camp Hill, an outlying
research unit of the Experiment Station, compared the effects of an
intense, hot fire to a mild fire. Hot fires will reach farther into
the canopy and destroy more of the understory and midstory vegetation
in the woods while a mild fire will destroy less of the understory.
"A mild fire tends to have a patchy burn where some areas burn
pretty clean and other areas don't," said Stribling. "We wanted
to see if the different types of burning would favor different types
of birds."
Since identifying the birds by their songs was easier than identifying
them visually, Stribling enlisted Michael Barron, a graduate research
assistant with an ear for music.
"Music has always been my other passion," said Barron, who
will soon complete his masters in zoology and wildlife science from
Auburn. "I already knew some basic bird songs and Dr. Stribling
thought that, since I had a musical background, my ear would be more
attuned to distinguish the different songs."
Though he was more accustomed to applying his talents in a church choir
or college chorus, Barron found his musical aptitude functioned well
in the great outdoors.
"The most intense time for birds to sing is from just before dawn
to about an hour after sunrise." said Barron. "They also sing
more during mating season (March and April) when they are trying to
attract a mate. That's when I had to be out there."
Results of the study showed that the areas where mild fires had burned
supported a greater number of birds and more bird species than areas
where hot fires had burned. Barron also found that the two types of
fire tended to affect birds that lived in the trees differently than
those that spent most of their time on the ground.
"The birds that nested or fed in the tree tops, tree cavities or
shrubs were found in greater numbers in the mild burn areas," said
Barron. Birds in this group included pine warblers, red-eyed vireos,
tufted titmice, Carolina wrens and chickadees, northern cardinals and
chipping sparrows. "The birds that nested or fed on the ground,
such as the Louisiana water thrush and rufus-sided towhees, were more
abundant in the hot burn areas," he added.
These results suggest that landowners interested in using prescribed
burning while maintaining certain bird species and numbers should carefully
choose their burning practices. Barron said that songbird populations
are good indicators of the ecological well-being of an area and also
offer aesthetic benefits by bringing the woods alive with their music.
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By:
Katie Smith
June 5, 1991
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