A study of how many dolphins are caught in tuna fishing nets estimates the mammals may now be at just 13 percent of their numbers prior to 1980. James Cook University’s Dr. Putu Mustika was part of an international group that looked at the bycatch from tuna gillnets (including driftnets) in the Indian Ocean. The group was led by Dr. Charles Anderson of the Manta Marine organization in the Maldives.