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Fig. 10.2 Domburi, a fish attraction device used in Shibushi area by Japanese fishermen
(Reproduced with permission from Yan et al. 2010 )
hearing capacity of local fishes. To evaluate the effect of such sources of noise on
some fishes ( Chromis chromis, Sciaena umbra , and Gobius cruentatus ) these
authors played back in the laboratory the recording of a ship noise and the sound
pressure level. The auditory sensitivity was evaluated recording the auditory
evoked potential recording. For all species, the masking effect of boat noise clearly
resulted in interference with the acoustic communication.
Habitat isolation is an important driver in communication system, especially
when isolation means difficulties to transmit cultural traits of an acoustic repertoire.
Dialects in birds are example of the presence of barriers that restrict the circulation
of individuals. Dialects, although this is a controversial argument, represent the first
step of genetic isolation.
Habitat loss is a further menace to the persistence of species, populations, and
behavioral traits. Small areas support small populations that can experience a
decreasing variety of acoustic traits, and signal modification has a direct effect on
the reproductive results. In fact, if the acoustic signal is an “honest signal” the
deterioration of this trait could open the way to non-honest competing systems with
high risk to lose some of the genetic integrity. Deterioration of signals can have
effects not only on reproductive success but also in efficiency in intercepting
resources or maintaining social cohesion.
Land transformation, with the changes of the spatial aspects of the landscape by
changing density and position of trees (from savanna like to linear hedgerows, for
instance), modify the sonic environment. Consequently, this change can cause the
disappearance of some vocal species even if other resources such as nesting sites or
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