Prey abundance, channel structure and the allometry of growth rate potential for juvenile trout

Authored by J S Rosenfeld, J Taylor

Date Published: 2009

DOI: 10.1111/j.1365-2400.2009.00656.x

Sponsors: No sponsors listed

Platforms: No platforms listed

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

The application of a drift-foraging bioenergetic model to evaluate the relative influence of prey abundance (invertebrate drift) and habitat (e.g. pool frequency) on habitat quality for young-of-the-year (YOY) and yearling juvenile cutthroat trout, Oncorhynchus clarki (Richardson) is described. Experiments and modelling indicated simultaneous limitation of fish growth by prey abundance and habitat, where depth and current velocity limit the volume of water and prey flowing through a fish's reactive field as well as swimming costs and prey capture success. Predicted energy intake and growth increase along a depth gradient, with slower deeper pool habitat generating higher predicted growth for both YOY and yearling trout. Bioenergetic modelling indicated that fish are constrained to use progressively deeper habitats to meet increasing energy requirements as they grow. Sensitivity of growth to prey abundance identified the need to better understand how variation in invertebrate drift and terrestrial drop affects habitat quality and capacity for drift-feeding fishes.

Tags

Atlantic salmon Individual-based model Habitat-selection Drift-feeding salmonids Coho salmon Rainbow-trout Net energy-intake Grayling thymallus-arcticus Bioenergetics models Salmon oncorhynchus-kisutch