Today I Learned (TIL)

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TIL that up to 70% of the sand on some white sandy beaches was excreted by parrotfish after eating coral (manoa.hawaii.edu)

submitted 1 day ago* (last edited 1 day ago) by otter@lemmy.ca to c/til@lemmy.ca

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Scientists estimate that up to 70% of the sand on white sandy beaches in the Caribbean and Hawai‘i has been excreted by parrotfish. A large adult parrotfish can excrete over a ton of sand per year. Areas that have parrotfish produce more sand than similar areas with few or no parrotfish. This sediment production rate is especially important in areas like Hawai‘i, where there is little terrestrial input, and almost all of the sand is of biogenic origin.

https://manoa.hawaii.edu/exploringourfluidearth/physical/coastal-interactions/beaches-and-sand/weird-science-parrotfish-and-sand

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[–] shalafi@lemmy.world 13 points 1 day ago

If you snorkel near coral around here you can hearing them chewing away. Sounds like popcorn, and there is an amazing amount of popping going on.

And yes, our beaches are pure white.