Applications - Soundscape Ecology: Principles, Patterns, Methods and Applications - page 261

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Fig. 10.1 Distribution of the recent number of papers regarding “Conservation Bioacoustics:” the
exponential growth since the year 2000 is evident (Reproduced with permission from Laiolo 2010 )

Several animals, such as humans, bony fishes, amphibians, reptiles, birds, and
mammals, and invertebrates, such as insects, spiders, crustaceans, and nematodes,
use acoustic mechanisms for courtship, territorial defense, and social behavior. In
some groups the acoustic repertoire is simply innate, but in others as in humans or in
some groups of birds, it is learned.
Communication is the most powerful semiotic process by which organisms
provide information on individual status, mood, and intention. Humans use the
interspecific communication process to catch resources. For instance, the great
sensitivity of fishes to acoustic cues has been used in fisheries for some time. Fish
schools can be driven into nets using the sound of Risso's dolphin ( Grampus
griseus ), and the “Damburi” or “boko” is a traditional Japanese fishing methods
to capture red sea bream ( Pagrus major ). This device is composed of a conically
shaped lead (Fig. 10.2 ) suspended by a rope 7 m long that is immersed in the water,
creating a column of tiny bubbles that attract fish to the nets (Yan et al. 2010 ).
In urban areas where the noise impact is strongest, some birds to avoid the
masking produced by traffic noise have shifted song frequencies, duration, ampli-
tude, and timing of singing. The shift of frequency probably represents a trade-off
between noise masking and quality of the acoustic message. A high pitch increases
sound propagation but a low-frequency sound is more informative for the quality of
the signaler than the higher frequencies to which species have to adapt. In several
cases, large birds that cannot change the frequency of their sounds prefer to
abandon or avoid noisy areas to reduce the impact of noise.
In the marine environment, noise pollution has reached dramatic levels because
of the greater propagation of acoustic waves in waters. Ship traffic, work in the
harbors, and the use of military and commercial sonar affects pelagic fishes, whales,
dolphins, and pinnipeds.
Experiments conducted in a marine protected area (Miramare, Italy) by Codarin
et al. ( 2009 ) have demonstrated how boating and shipping negatively affect the