Indigenous Australian seasons
Indigenous Australian seasons are often classified differently than the traditional four-season calendar used by contemporary Australians. Aboriginal Australians and Torres Strait Islander people have distinct ways of dividing the year up. Naming and understanding of seasons differed between groups of Aboriginal peoples, and depending on where in Australia the group lives. The Australian Bureau of Meteorology and the CSIRO have both worked with various groups to produce information about a number of Aboriginal and Torres Strait Islander seasonal calendars. Background. Aboriginal and Torres Strait Islander peoples observe the position of the stars in the sky and  follow water, plant and animal cycles as ways of identifying seasonal phenomena. The seasonal calendars of different Aboriginal and Torres Strait Islander cultural groups demonstrate an understanding of the interdependence and interrelationships amongst living things. They use their calendars to predict seasonal changes and weather patterns to determine the availability of particular resources or the timing of journeys. The seasonal calendars vary according to geographic location, ecological context and cultural interpretation. Specific biotic events, often referred to as bio-indicators, can occur locally or over great distances, enabling accurate predictions of seasonal changes. For instance, the appearance of particular insect  species may be an indication that the wet season is approaching, indicating that it is time to harvest yams. Observations of cyclical animal behavioural patterns are also important, for example when the D'harawal people of the Sydney basin area hear the mating cries of tiger quolls, the lillipilli fruit has started to ripen. Once the fruit starts falling, it is a sign for the people of this country to begin their annual journey to the coast, to seek out other seasonal resources. Seasonal calendars continue to be used by many groups today. The publication of First Nations' calendars has revealed  the immense scientific knowledge held by the respective communities and has informed Western scientific understandings across a wide range of disciplines, for example, botany, zoology, ecology, meteorology and many more. BOM and CSIRO resources. The Bureau of Meteorology (BOM) and the CSIRO have both worked with various groups to produce Aboriginal and Torres Strait Islander seasonal calendars. BOM has produced an interactive map, and both BOM and the CSIRO have also documented the seasonal calendars of many Aboriginal groups in detail. Both sites provide downloadable and printable posters showing each group's calendar. Some Aboriginal seasons. North coast – Yolngu seasons . The Yolngu, the Aboriginal Australians of North-East Arnhem Land, identify six seasons. Non-Indigenous people living in the Top End usually identify two: the Wet and the Dry. (Arguably, the "build-up" period between dry and wet is coming to be identified as a distinct third season.) The six Yolngu seasons, and their characteristics, are: Central – Anangu Pitjantjajara seasons. The Anangu Pitjantjatjara of northern South Australia and the southern part of the Northern Territory live in central Australia. Examples of some of their seasons include: South-west – Noongar seasons. Noongar seasons do not follow a rigid cycle; timing is  dependent on subtle changes in the weather with wind, rain and temperature. The cycles are part of "katitjin-bidi" or "knowledge trails" that lead groups to reliable sources of food and water. The seasons are named as follows by the Whadjuk Noongar people of Perth: Torres Strait Islands seasons. In the Torres Strait Islands, the seasons are associated with the way the wind blows and changes in the environment. The four seasons based on the wind are known as Kuki, Zey (Zei in Masig) and Nay Gay (Nai Gai in Masig) and Sager (Zoerr): The people of Masig (otherwise known  as Yorke Island), known as the Masigalgal, are part of the Kulkulgal nation of the central Torres Strait. The timing and duration of these four seasons varies from year to year, and Masig islanders observe signs in the winds, weather, sea life, plants and animals that tell them when one season is expected to change to another. Community celebrations, hunting, gardening and cultural activities are based around this annual cycle of resource availability and renewal.