Large‐scale assessments of river health using an Index of Biotic Integrity with low‐diversity fish communities

SUMMARY 1. Effective tools are needed to measure the ‘health’ of rivers at scales large enough to be useful for management. Indicators for assessing the complex of variables that constitutes river health need to be ecologically based, efficient, rapid and consistently applicable in different ecological regions. 2. A large-scale survey of rivers in New South Wales, Australia provided data to test the Index of Biotic Integrity (IBI). The IBI employs the fish-community attributes, identified using regional and river-size data, expected for a river reach of excellent environmental quality. It uses metrics based on species richness, abundance, community structure and the health of individual fish. IBI metrics were established to suit a relatively low-diversity and unspecialized freshwater fish fauna in south-eastern Australia, totalling 55 species. 3. The IBI was able to discriminate between relative levels of environmental quality within a diverse set of stream systems and four presumptive ecological regions. The index was validated by testing the repeatability of scores, and by comparison of IBI scores at eighty sites with an independent measure of potential catchment condition, the River Disturbance Index. 4. Assessments of metric performance showed that eleven of the twelve metrics contributed satisfactorily. One metric based on trophic guild performed poorly and should be deleted from the index. Six other recommendations are made to enhance the performance of the IBI. 5. Results show that, while all large rivers have been disturbed, rivers in the Murray region and those in many coastal montane areas are particularly degraded. 6. The IBI results presented here demonstrate a validated method for large-scale monitoring of river health based on a fish fauna of limited diversity, in the absence of suitable reference sites.

[1]  Robert J. Steedman,et al.  Modification and Assessment of an Index of Biotic Integrity to Quantify Stream Quality in Southern Ontario , 1988 .

[2]  J. Walker,et al.  Indicators of catchment health: a technical perspective. , 1996 .

[3]  M. Barbour,et al.  A Framework for Biological Criteria for Florida Streams Using Benthic Macroinvertebrates , 1996, Journal of the North American Benthological Society.

[4]  A. James,et al.  Biological indicators of water quality , 1979 .

[5]  J. Walker,et al.  Indicators of Catchment Health , 1996 .

[6]  J. Karr Assessment of Biotic Integrity Using Fish Communities , 1981 .

[7]  James R. Karr,et al.  Biological monitoring and environmental assessment: a conceptual framework , 1987 .

[8]  J. Connell Diversity in tropical rain forests and coral reefs. , 1978, Science.

[9]  Richard H. Norris,et al.  The need for biological assessment of water quality: Australian perspective , 1995 .

[10]  J. Harris Diet of the Australian bass, Macquaria novemaculeata (Perciformes : Percichthyidae), in the Sydney Basin , 1985 .

[11]  B. Chessman,et al.  Rapid assessment of rivers using macroinvertebrates: A procedure based on habitat‐specific sampling, family level identification and a biotic index , 1995 .

[12]  J. F. Wright,et al.  Development and use of a system for predicting the macroinvertebrate fauna in flowing waters , 1995 .

[13]  James R. Karr,et al.  Regional Application of an Index of Biotic Integrity Based on Stream Fish Communities , 1984 .

[14]  Michael Reid,et al.  ESTABLISHING THE CONDITION OF LOWLAND FLOODPLAIN RIVERS : A PALAEO-ECOLOGICAL APPROACH , 1999 .

[15]  K. Walker,et al.  Irrigation development on Cooper Creek, central Australia—prospects for a regulated economy in a boom‐and‐bust ecology , 1997 .

[16]  James R. Karr,et al.  Assessing biological integrity in running waters : a method and its rationale , 1986 .

[17]  John H. Harris,et al.  The use of fish in ecological assessments , 1995 .

[18]  J. Allan,et al.  The influence of catchment land use on stream integrity across multiple spatial scales , 1997 .

[19]  P. Gehrke,et al.  River regulation and fish communities in the Murray-Darling River system, Australia , 1995 .

[20]  James R. Karr,et al.  Applying an Index of Biotic Integrity Based on Stream-Fish Communities: Considerations in Sampling and Interpretation , 1986 .

[21]  D. M. Day,et al.  Influence of Stream Location in a Drainage Network on the Index of Biotic Integrity , 1992 .

[22]  R. Callinan,et al.  Pathology of red spot disease in sea mullet, Mugil cephalus L., from eastern Australia. , 1989 .

[23]  J. Karr Biological Integrity: A Long-Neglected Aspect of Water Resource Management. , 1991, Ecological applications : a publication of the Ecological Society of America.

[24]  Leska S. Fore,et al.  Statistical Properties of an Index of Biological Integrity Used to Evaluate Water Resources , 1994 .

[25]  P. Davies Relationships between habitat characteristics and population abundance for brown trout, 'Salmo trutta L.', and blackfish, 'Gadopsis marmoratus Rich.', in Tasmanian streams , 1989 .

[26]  R. Hobbs Australia: State of the environment 1996 , 1997 .

[27]  R. McDowall The relationships of Australian freshwater fishes , 1981 .

[28]  John Lyons,et al.  Development and Validation of an Index of Biotic Integrity for Coldwater Streams in Wisconsin , 1996 .

[29]  James R. Karr,et al.  A Benthic Index of Biotic Integrity (B-IBI) for Rivers of the Tennessee Valley , 1994 .

[30]  James R. Karr,et al.  Rivers as Sentinels: Using the Biology of Rivers to Guide Landscape Management , 1998 .