Mantanomics demonstrates the economic value of manta rays, which are much more valuable as long-term sources of tourism revenue than as one-time revenue to fisheries. This study estimates the direct economic impact ($140 million per year) from tourism, which significantly exceeds the value of trade in manta ray gill plates ($5 million per year).
In 2014, Indonesia declared the largest manta ray sanctuary in the world. The Ministry of Marine Affairs and Fisheries granted full protected status that supports a US$ 15 million tourism industry per year. It is ranked as one of the top three destinations in the world for manta ray watching, mainly in West Papua.
Here is the link to the paper:
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0065051
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