this is a flawed argument as wild populatons are in fact booming.
In Brazil people are paid to kill rays to keep popular beaches clear and Japanese factory freezer ships are allowed to take rays out 200 tonnes at a time, when the ornamental fish export represents less than 2% of all the rays taken.
Fishing and export represents a sustainable renewable income for thousands of people in Amazonia, , they are alowed to kill and eat a ray, god for one meal, but not allowd to export a ray, god fopr a weks' worth of income.
Big corporations are able to pay the steep prices to get around restrictions or to distort policy set by politicians and not by scientists, despite scietific advice.
The vast majority of scientific comunity there wants the quotas raised and any bans lifted.
The next big threat to all Amazon fish populations is loss of habitat and pollution, and that also is nothing to do with fishing, but entirely due to human greed for gold and other minerals, exotic hard woods etc.
Meanwhile some senior gov. officials will grant permits for rays to be exported if you pay a large enough "fee".
My associates and I wanted to start a farm for rays and other species and were asked to pay $100, 000 in cash for the permit to the official in charge