Detection Range and Sensitivity
Ideally, the range over which a bat is detected should
be as large as possible. This allows the sampled area to
be larger and the number of observations higher. Greater
range allows for an earlier detection of bats resulting in
a longer observation time, which enhances recording
and identification possibilities.
Detection range depends on several variables that
include the frequency range and strength (amplitude) of
the emitted signal, the sensitivity of the microphone to
different frequencies, the orientation of the bat to the
microphone, whether the bat is flying in open or cluttered
airspace, and atmospheric conditions. The amplitude
of calls and the signal type used by the species of
bat (Fig. 2) are
dependent on hab -
itat and the distance
a bat is from
surrounding obstacles
that produce
clutter (i.e., echoes
from objects other
than the target,