 Byron charted the atolls as "Lagoon Islands".Keith S. Chambers and Doug Munro (1980) identified Niutao as the island that Francisco Mourelle de la Rúa sailed past on 5 May 1781, thus solving what Europeans had called "The Mystery of Gran Cocal".Mourelle's map and journal named the island "El Gran Cocal" ('The Great Coconut Plantation'); however, the latitude and longitude was uncertain.