This article reports on how the people of the Tiwi Islands (which lie in the Arafura Sea located off the coast of Darwin in Australia's Northern Territory) have carefully observed the rhythms and patterns of their country, developing a complex and precise way of living sustainably in their island environment. In 2015, the Tiwi people shared their knowledge with the release of two Tiwi calendars. "Tiwi Seasons" shows the islands' three major and 13 minor overlapping seasons, and "Tiwi Plants and Animals" shows plants and animals that are important to the Tiwi people, and when they might be collected. These calendars will help conserve and protect Tiwi knowledge. They will help the children to learn about their culture and to become strong Tiwi people. The calendars will be used across the Tiwi Islands to help pass on traditional ecological knowledge. (The calendars are available at: http://www.csiro.au/en/Research/%20Environment/Land-management/%20Indigenous/Indigenous-calendars/Tiwi).