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Title: Biological problems associated with IFIM and implications for regional fisheries studies
Author: D.J. Bird
Document Type: Monograph
Annotation: EA additional title info: fisheries technical report
The objectives of the Instream Flow Incremental Methodology (IFIM) are appropriate for addressing a wide variety of water resource management problems. The Region has used the technique in recent studies and is interested in expanding its use to additional ecological types of river (e.g. River Tavy, Malmesbury Avon). Concerns have been identified in this review regarding the modelling of habitat selection data by the Physical Habitat Simulation System (PHABSIM) to predict flow requirements. These difficulties are summarized below: Lack of cost effective strategies for developing habitat suitability criteria; Physical habitat not limiting populations; Inappropriate choice of species/life stages; Inadequate choice of habitat variables; Ignorance of the relative importance and interaction of habitat variables; Sampling error in habitat variable measurements; Unrealistic interpretation of habitat suitability criteria; Inappropriate transferability of habitat suitability criteria; Inappropriate choice of PHABSIM reach; Ignorance of temporal habitat variation. For salmonids, many of these issues can be addressed in properly designed studies. Detailed, field based habitat selection studies'should be restricted to critical periods and life stages (e.g late summer juveniles) and should be supported by carefully chosen criteria from the literature for other periods and life stages. These criteria should be transferable to a variety of streams that share the same ecological attributes. To this end, it is proposed that criteria are developed and selected for high gradient, soft water streams within the Region and used for the Tavy ALF investigation.
Publisher: National Rivers Authority
Publication Date: 1995
Publication Place: [Bristol]
Subject Keywords: Regional planningFisheriesRiversHabitat improvementFlow rateModellingSalmonidae
Geographic Keywords: EA South West
Extent: n.p. [21]
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