Marshall Islands Stick Chart, Marshall Islands, Kwajalein. The bamboo slats represent routes to specific places marked by the shell, such as islands. Reproduction, The Mariners’ Museum.
As Captain James Cook was conducting his voyages of exploration and discovery, Polynesian navigators had already successfully explored and settled the islands from New Zealand to Hawaii. Remarkably, the Polynesians had developed a sophisticated and reliable means of wayfinding based not on science and mathematics, but rather on their innate knowledge of the seas and sky.
By using the sun, stars, sea swell patterns, cloud formations, and seamarks such as bird flight habits, Polynesian navigators were able to steer their canoes over distances that amazed European navigators – including the two thousand miles between Tahiti and the Hawaiian Islands.
The Polynesian star compass was the key to finding direction at sea. The four cardinal points (north, south, east, and west) were located according to the rising and setting sun. During night voyaging, stars formed reference points. Polynesian navigators memorized the star compass as well as known islands whose locations corresponded to points of the compass. In training, a navigator would name an island as the center point, then go around the compass points naming the islands that lay in each direction.
Beyond navigating by the sun and stars, the Polynesians used their extensive knowledge of the sea to successfully guide them through their voyages. By careful observation of sea swell patterns, wind direction, cloud formations, and patterns of bird flight and flotsam, traditional Pacific navigators pieced together the course they chose to follow.
Sea Swells: Sea swells are waves that have moved beyond the wind or storms that generated them. Swells tend to be more regular and persistent in their flow than waves. By observing the swells and understanding the winds that created them, Polynesian navigators could steer their canoes according to the swell patterns. Interestingly, swells are more easily felt than seen.
Winds: Winds were also used to determine direction. However, wind changes could occur during the course of a day’s voyage. To better observe these changes, Polynesian navigators fixed lightweight wind pennants made of feathers and bark to the masts of their canoes.
Cloud Formations: As clouds moved over sea and land, the Polynesians noted that clouds tend to be drawn to land in distinctive “V” formations. This cloud pattern is created by the reflection of heat radiated from the island. Many navigators also noted slight color changes in clouds over land, and were able to distinguish the landform from the color; a slight green indicated lagoon islands, bright clouds indicated sand, and dark clouds marked forested areas.
Flight of birds: Flight patterns of specific species provided a reliable means of determining the direction of land. The fairy and noddy terns were especially important, as both species nest on land, and neither swims. Both terns fly to sea in the morning and return to land at dusk. By observing the habits of these birds, Polynesian navigators could not only determine the direction of land, but also its approximate distance. Fairy terns have a flight range of about one hundred twenty miles, while noddy terns have a range of about forty miles.
Flotsam: Floating debris such as palm fronds, coconuts, and other vegetation also signaled nearby land.
Experimental “wayfinding” has been traditionally performed in Micronesia, and is regaining credence as an art in Polynesia.