This Technical Report presents the outcome of a Working Group that was
established to determine broadly applicable sound exposure guidelines
for fishes and sea turtles. After consideration of the diversity of fish
and sea turtles, guidelines were developed for broad groups of animals,
defined by the way they detect sound. Different sound sources were
considered in terms of their acoustic characteristics and appropriate
metrics defined for measurement of the received levels. The resultant
sound exposure guidelines are presented in a set of tables. In some
cases numerical guidelines are provided, expressed in appropriate
metrics. When there were insufficient data to support numerical values,
the relative likelihood of effects occurring was evaluated, although
the actual likelihood of effects depends on the received level. These
sound exposure guidelines, which are based on the best scientific
information at the time of writing, should be treated as interim. The
expectation is that with more research the guidelines can be refined and
more cells in the tables completed. Recommendations are put forward
defining the research requirements of highest priority for extending
these interim exposure guidelines.