Appendix B: Additional details for the analysis of the PONSE data set

A mixed-model moving-average approach to geostatistical modeling in stream networks. Ecology 91:644–651. South East Queensland (SEQ) is located on the eastern coast of Australia and is approximately 22,999 square km in size. It is a subtropical region with mean annual maximum temperatures ranging between 21 and 29 °C (EHMP, 2001) and total annual rainfall ranges between 900 and 1800 mm (Pusey et al. 1993). Elevation ranges between 0 meters in coastal areas to 1360 meters in the west along the Great Dividing Range. Regional discharge is seasonally variable and is related to elevation, slope, and rainfall (EHMP, 2001). The predominant land uses in the region are natural bushland (37%) and grazing (35%). The Ecosystem Health Monitoring Program (EHMP) has been collecting indicators of biotic structure and ecosystem function throughout SEQ since 2002 (Bunn et al. in press). The program aims are to evaluate the condition and trend in ecological health of freshwater environments and to guide investments in watershed protection and rehabilitation. Metrics based on fish assemblage structure and function are commonly used as indicators of ecological health because they are thought to provide a holistic approach to assessment across broad spatial and temporal scales (Harris 1995). The EHMP uses ecosystem health indicators based on freshwater fish species richness (Kennard et al. 2006a), fish assemblage composition (Kennard et al. 2006b) and the relative abundance of alien species (Kennard et al. 2005). In this example, we used a model-based fish indicator, the proportion of native fish species expected (PONSE), which is the ratio of observed to expected native fish species richness (Bunn et al. in press, Kennard et al. 2006a). Here, species richness is simply the number of native fish species observed or predicted