Later that day I saw a Chinese man drying out hundreds of sea slugs on racks, getting ready to send them away. I inquired about the fishery - explaining that I was an ex-commercial freediver - and he told me that he would pay me $17 for each one that I could catch.
I was disgusted that people would allow this obvious destruction to happen right in front of their eyes. The Chinese Government provides significant funding for development in places like Tonga in return for access to un-patrolled and largely un-fettered fishing grounds that, once exploited like they are with the sea slugs, may never recover.
You see, reefs (other than providing us waves to surf) are really important. In the Caribbean, where over 50 per cent of the reefs have been lost since 1970, over $3 billion is generated by reefs for tourism and fishing, with more than a hundred times this in other goods and services.
But when people have experienced something so spectacular as healthy coral reefs underwater and they see them dying, it sparks serious emotion and action. A scientific report on solutions to the plight of reefs has shown that if we look after the "grazers" - species that clean the reefs of algae - then we can turn the tides on the problem and even re-establish an ecosystem.
But even if management practices are changed, in some areas the destruction is so heavy that not a fish is to be found.
Enter Thomas Goreau, son of the founder of the world's first diving research club, who I met when I spoke at the United Nations Conference on Land-Ocean Connectedness in Jamaica last year.
Goreau is your archetypal scientist with wild hair, thick glasses, slacks, socks and sandals - though to my surprise, when I sat with him for lunch he promptly ordered a rum and coke.
By studying how shellfish grow he has managed to create a substance they call biorock which is much like a common shell. They implant this onto the ocean floor and attach coral to it, which takes off like a rocket - up to five times as fast as in normal conditions.
They say that the same biorock substance can be used for the construction industry and greatly reduce the impact of concrete on fossil fuels, but that is another story altogether.
Goreau's work in Indonesia picked up the United Nations Development Program's Special Award for Marine and Coastal Zone Management as well as the Equator Award for Community Based Development.
Rightly so I say - this is another excellent example of innovative science helping us to mend the errors of our ways: similar projects are underway in 20 different countries across the tropical, coral-growing regions of the world.
Do you have any examples of scientific solutions that will help us to fix things like dying reefs? Please send me an email.