Curved Stone Fish Traps at Low Tide

Curved Stone Fish Traps at Low Tide is an original illustration set in Mer Island, Torres Strait, Australia. It lies in equatorial latitudes, where the climate is tropical savanna — a pronounced dry season.

At low tide, several long curved walls of dark volcanic stone arc across a turquoise reef flat, enclosing shallow pools that glint with trapped fish. Meriam rangers repair gaps by hand, small boats wait beyond the walls, and the steep green volcanic profile of Mer rises from the eastern Torres Strait.

Why do curved stone walls open toward the falling tide?

The walls are low enough for a rising tide to cover them, allowing fish to move onto the reef, but as water falls the curved enclosures retain pools and guide fish toward accessible gaps. Local volcanic stone withstands repeated immersion and can be reset communally after storms. Intertidal arcs, reef-flat timing, hand gathering, and a high volcanic island make the geometry a working sai system rather than an abandoned seawall.

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