Following shall be done by the OOW in order to keep a check on the vessel's position while she is on anchor -
OOW shall comply with the Master's Standing Orders / Night orders along with company's standing orders.
The position of the ship is required to be fixed by:
(a) Visual Anchor Bearings
(b) Radar Range and Bearing
(c) Global Positioning System (GPS)

Additionally, the OOW shall -
(a) monitor weather conditions
(b) monitor weather forecast
(c) monitor other ship's position in the vicinity
(d) monitor VHF Ch 16 for communication from VTS