In the Ancient Hawaiian aquaculture, fishponds were located next to the mouth of a stream and had porous lava walls that let in seawater (or sometimes fresh or brackish water, as in the case of the "Menehune" fishpond, a historic Hawaiian fishpond listed on the U.S. National Register of Historic Places, near Līhuʻe, Kauaʻi), but prevent the fish from escaping.
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