Split Anchor-Watch Rotas Driven by Garden Signals

A container vessel anchored off Singapore waiting for a berth can sit on the hook for four days. The anchor watch rota often gets drafted as a flat split of the bridge team against the clock. Wind shifts, squalls, and tidal changes say the rota should be drafted against the officers' circadian bands instead.

A container vessel waiting for a berth off Eastern Anchorage, Singapore, settles into anchor watch for what looks like a short stop and turns into four days. The Master draws a rota against the clock. Chief Officer: 00:00 to 06:00 and 12:00 to 18:00. Second Mate: 06:00 to 12:00 and 18:00 to 00:00. Clean. Symmetrical. Easy to defend if the P&I club asks. The bosun holds a standing deck round every two hours to check the anchor chain, and the engine room keeps a reduced watch on the main engine. Paper-wise, the operation is textbook.