One myth that seems not to want to go away is that of dolphins not being
able to use their sonar whilst in captive care. Animal-rights activists
and groups continue to perpetuate this myth despite their being no actual
scientific evidence to support this contention.
A brief review of animal-rights literature will find quotes such as:
the wild dolphins use sonar to "see" and to communicate.
In captivity they are unable to use sonar because of sound waves bouncing
off tank walls."
the most glaring fault with such statements is that they choose to ignore
the simple fact that much of the pioneering and continuing research
on sonar and dolphin vocal communication has taken place using captive
animals (see over view in Norris, 1991).
Moreover, in public demonstrations animals are regularly asked to demonstrate
their sonar abilities by being blindfolded and can be seen successfully
seeking and retrieving objects for their trainers. In point of fact
sonar bouncing off objects (e.g. a tank wall) work because animals such
as dolphins exploit this effect to see with sound.
In fact, during the research for the UK's Review of Dolphinaria the
authors, Dr. Margaret Klinowska and Dr. Susan Brown, visited a number
of dolphinaria and successfully recorded animals making both vocalisations
and sonar sounds (Klinowska
and Brown, 1986). It should be further noted that a dolphins sonar
is like the human voice in as such the animals can control the volume
and pitch of sonar.
Klinowska, M. and Brown, S. (1986). A Review Of Dolphinaria,
London: Department of the Environment.
Norris, K. (1991). Looking at Captive Dolphins. In Pryor, K. and Norris,
K. (Eds) Dolphin Societies: Discoveries and Puzzles. Oxford:
University of California Press.
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