Generalized instream habitat models

• Published in: Canadian journal of fisheries and aquatic sciences Vol. 62; no. 1; pp. 7 - 14
• Main Authors: Lamouroux, Nicolas, Jowett, Ian G
• Format: Journal Article
• Language: English
• Published: Ottawa, Canada NRC Research Press 01.01.2005; National Research Council of Canada; Canadian Science Publishing NRC Research Press
• Subjects: Anguilla dieffenbachii; Animal and plant ecology; Animal, plant and microbial ecology; Aquatic life; Barbatula barbatula; Barbus barbus; Biological and medical sciences; Calibration; Cheimarrichthys fosteri; Coloburiscus humeralis; Environmental Sciences; Fresh water; Fresh water ecosystems; Freshwater; Froude number; Fundamental and applied biological sciences. Psychology; Galaxias maculatus; General aspects. Techniques; Gobiomorphus breviceps; Gobiomorphus huttoni; Habitat changes; Habitats; Hydraulics; Methods and techniques (sampling, tagging, trapping, modelling...); Microhabitats; Oncorhynchus mykiss; Particle size; Phoxinus phoxinus; Rivers; Salmo trutta; Streams; Synecology; Taxa; Taxonomy; Water depth; New Zealand; France; Europe; Oceania; Freshwater environment; Aquatic environment; Hydraulics; River discharge; Riverflow control; Water engineering; Habitat; Models; Rivers; Comparative study; NOUVELLE ZELANDE; LHQ; CEMAGREF; BELY
• ISSN: 0706-652X; 1205-7533
• DOI: 10.1139/f04-163

Conventional instream habitat models (e.g., the physical habitat simulation system) predict the impact of regulation on the habitats of freshwater taxa. They link a hydraulic model with microhabitat-suitability models for taxa to predict habitat values at various discharge rates. Their use requires considerable field effort and experience. Recent analyses performed in France suggested that comparable results could be achieved using simplified hydraulic data. We tested this approach for 99 stream reaches and nine aquatic taxa in New Zealand. The resulting generalized habitat models predict habitat values similar to those predicted by conventional models from simplified hydraulic data (depth–discharge and width–discharge relationships, average particle size, and mean annual discharge). As in France, within-reach changes in habitat values were linked to the specific discharge of reaches, while between-reach changes depended mainly on the Froude number at mean annual discharge. The generalized models perform well outside their calibration range. Models previously developed in France perform well in New Zealand. Such generalized models contribute to identifying the key hydraulic variables for freshwater taxa and should facilitate habitat studies worldwide.