This presentation will explore the use of the chemical and isotopic signatures in ear stones (otoliths) from modern and ancient golden perch to track the changing cycle of flooding and drying in one of the earliest sites of human occupation in Australia.
Inland archaeological sites in the Australian arid zone contain few records of past environments. For those archives that do exist, such as sedimentary records, it is difficult to associate the environmental conditions that they record directly with the time scales of human occupation. At the world heritage site of Lake Mungo, in north western New South Wales, lake shore dunes preserve a record of human occupation, and of alternating phases of wet and dry conditions in the adjacent lake. Dunes often form over a much longer time period than a human lifetime, making it difficult to match specific climatic events that would have had a direct impact on past peoples within their lifetimes.
Golden perch are fish that can live up to 40 years, a period comparable to a human life span. As the fish grow so do their otoliths, preserving a record of the changing chemical and isotopic composition of the water in which the fish lived. Otoliths are abundant within the Lake Mungo lunettes, preserving an untapped record of past changes in lake levels and environmental conditions that, in the case of fish from hearth sites, can be associated directly with human occupation.