On any night when the Half Moon is at anchor, the student crew must maintain a watch till dawn to monitor the safety of the ship and its crew. From 2200 hours to our assigned wake-up time (typically 0700 hours), pairs of students (along with however many senior crew are needed to fill out the roster) each rise for one-hour shifts to watch over three crucial aspects of our anchorage:

Anchor Dragging: In the event of high winds or currents, it is possible for the ship's anchor to lose its purchase on the bottom and drag along as the ship drifts out of control. An alert crew can notice this hazard and react reset the anchor; without a perceptive Anchor Watch, however, the ship could drift into shallow waters or out into a busy channel of water traffic.

The Anchor Light: When the ship is at anchor, we raise a marker from the fore mast. Its light shines at night, and during the day the marker is visible as a black ball. This anchor light is standard maritime practice. At night, it alerts passing vessels to our location, and regardless of the time of day it informs other vessels that we are at anchor and are thus stationary. During the night, the Anchor Watch teams must keep an eye on the anchor light to ensure it does not go out.