Prior to the 20th century, New York City was considered the oyster capital of the world. Today, New York Harbor’s oyster population is a shadow of its former self, but one group is teaming up with local restaurants to change that.

As Observer reports, the Billion Oyster Project (BOP) aims to replenish the area with at least one billion live oysters by 2030. Since it was formed in 2014, the group has added 17 million of the shellfish to the bottom of the harbor.

To obtain the oyster shells used to grow new ones, BOP doesn’t have to look far. Up to half a million oysters are served in New York City eateries each week, and once they’ve been shucked and slurped clean, the shells don’t hold much value to restaurant owners. So far over 50 restaurants have signed up to donate their weekly oyster shell waste to the project. After it’s cured and prepared properly, one recycled shell can be used to grow as many as 20 new oysters.

Restoring the harbor’s oyster population to where it once was is just part of the equation. Oysters act as natural filters, with one oyster capable of cleaning up to 50 gallons of water a day. Oysters can help rid the harbor of organic waste, transforming it into a more hospitable environment for even more life. In an effort to reach their goal of one billion oysters in the next 14 years, BOP is adding several new reef sites this summer.

[h/t Observer]

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