Question for the keeper: daymark

Beacon #93

In addition to the usual spate of questions I get at the breakfast table about life as a lighthouse keeper, someone asked navigation question: What is a daymark?

A daymark is a distinguishing shape and color displayed on beacons to make them readily visible and easily identifiable against background conditions. As an aid to navigation, a daymark signifies during daylight what a light or reflector signifies at night. For instance, the beacon across Esopus Creek from the lighthouse is equipped with a flashing green light atop a steel tower and a rectangular green daymark on either side of the side of the tower. It marks the end of the jetty at the entrance to the creek channel.