Sici (common name: univalves; scientific name: trochus nilotucus)\u000b \n\nSigns/indicators of Sici - It is harder to pull as they are firmly stuck to the rocks.\u000b\n\nThis is classified as a waitui or sea categories when sici or univalves is very hard to pull as they are firmly stuck to the rocks. Some of the reasons why warnings are ineffective or people do not respond in a timely way are economic factors, lack of understanding, experience that official warnings are not always reliable, inconsistencies in the warnings, and warnings coming from a single source only. Cyclones in particular are unpredictable in their behavior, and so official warnings are often considered unreliable. People need to trust in the warnings and in the need to act upon those warnings. \n\nAncient early warning systems used by ancestors to predict an incoming natural disaster have been an integral part of saving lives long before the introduction of technology.\n