In proceedings for an offence against these regulations or any other
regulations made under the Act, if it is proved that a person apparently over
the age of 15 years was on board a registered boat on a particular day while
the registered boat was being used for the purpose of engaging in a fishing
activity of a class that constitutes a fishery, it will be presumed, in the
absence of proof to the contrary, that the person was on that day engaged in
the fishing activity for which purpose the registered boat was being used.