Development and Application of a Predictive Model of Freshwater Fish Assemblage Composition to Evaluate River Health in Eastern Australia

Abstract

Multivariate predictive models are widely used tools for assessment of aquatic ecosystem health and models have been successfully developed for the prediction and assessment of aquatic macroinvertebrates, diatoms, local stream habitat features and fish. We evaluated the ability of a modelling method based on the River InVertebrate Prediction and Classification System (RIVPACS) to accurately predict freshwater fish assemblage composition and assess aquatic ecosystem health in rivers and streams of south-eastern Queensland, Australia. The predictive model was developed, validated and tested in a region of comparatively high environmental variability due to the unpredictable nature of rainfall and river discharge. The model was concluded to provide sufficiently accurate and precise predictions of species composition and was sensitive enough to distinguish test sites impacted by several common types of human disturbance (particularly impacts associated with catchment land use and associated local riparian, in-stream habitat and water quality degradation). The total number of fish species available for prediction was low in comparison to similar applications of multivariate predictive models based on other indicator groups, yet the accuracy and precision of our model was comparable to outcomes from such studies. In addition, our model developed for sites sampled on one occasion and in one season only (winter), was able to accurately predict fish assemblage composition at sites sampled during other seasons and years, provided that they were not subject to unusually extreme environmental conditions (e.g. extended periods of low flow that restricted fish movement or resulted in habitat desiccation and local fish extinctions).

Hydrologic connectivity driven natural stream fish assemblages in mountain streams in the Yangtze River basin: implications for stream fish conservation in monsoonal East Asia

“…Freshwater fish assemblages along the spatial gradients of streams and rivers are generally assumed to be influenced by both natural factors and anthropogenic disturbances (Vannote et al, 1980;Allan, 2004;Kennard et al, 2006). Under natural conditions, patterns and processes observed in fish assemblages are strongly influenced by multiple factors operating over a range of spatial and temporal scales (Horwitz, 1978;Schlosser, 1987;Tonn, 1990;Oberdoff et al, 1995;Ostrand & Wilde, 2002;Hoeinghaus et al, 2007).…”

Ecological drivers of spatial variability among fish fauna of 21 tropical Australian estuaries

“…Furthermore, it cannot be assumed that variables that are important measures of ecosystem health in other ecosystems are suitable measures in tropical estuaries. For example, high fish species richness and abundance are recognised as sensitive measures of ecosystem condition in freshwater systems of tropical Australia (Kennard et al 2006); however, the lack of a relationship between richness or presence per net and the potential impact status of northeastern Australian estuaries suggests that these measures are generally not appropriate for the systems studied. Perhaps careful matching of typological profiles would allow these measures to be applied to 'similar' systems, but the complexity of tropical estuarine fauna makes this unlikely.…”

Status assessment and causal factors diagnosis of river system health

“…In past few decades, some evaluating index systems such as the index of stream condition (ISC) (Landson and White, 1999;Kennard et al, 2006), Environmental Monitoring and Assessment Programme (EMAP) (Huhges et al, 2000), the Isle of Man a River Habitat Survey (RHS) (Raven et al, 2000) have been developed. In these index systems, all variables related to a river system have been considered as the state variables of a river system.…”

“…As society had benefitted immeasurably from rivers (Karr, 1999), the rate and extent to which humans had altered rivers had been surpassing our ability to assimilate and understand the implications of our actions (Kay and Schneider, 1994;Kennard et al, 2006). It has resulted that many rivers have been becoming dramatically degraded (Karr, 1999;Pinto and Maheshwan, 2011).…”