Publication Abstract

Spatial and ontogenetic variability in microhabitat use of stream-dwelling spined loach (Cobitis taenia) and stone loach (Barbatula barbatula)

Spatial and ontogenetic variability in microhabitat use of stream-dwelling spined loach (Cobitis taenia) and stone loach (Barbatula barbatula)

G.H. Copp and L. Vilizzi

1. Ontogenetic and spatial variability in microhabitat use of spined loach Cobitis taenia and stone loach Barbatula barbatula was examined in the River Great Ouse basin, England.
2. Distinct ordinations of spined age and stone loach ecospecies (age classes and developmental stages, respectively) in canonical correspondence analysis of species-variables-samples relationships suggest that the two species occupy completely different microhabitats; however, young-of-the-year spined loach occurred more often than expected with all ecospecies of stone loach except one. Water velocity and filamentous algae were the most influential microhabitat variables, the latter decreasing in abundance with age in both species. Preferred water velocities generally decreased with age in spined loach and increased in stone loach, with substratum size generally increasing with fish age in both species.
3. Spatial variation in microhabitat preferences and weighted used areas was great in both species but less so in the spined loach, suggesting that limited plasticity in habitat use could account, at least in part, for the latter species’ limited distribution and abundance in the catchment.

Preferences in a species, if generated and verified for all life stages, could be used for a given stream or sector of river basin. But, preference curves should be generated for each location to ensure that river management decisions on habitat consider local-level species requirements. Thus, a multi-(eco)species and multi-scale approach is required.

Reference:

G.H. Copp and L. Vilizzi (2004) Spatial and ontogenetic variability in microhabitat use of stream-dwelling spined loach (Cobitis taenia) and stone loach (Barbatula barbatula). Journal of Applied Ichthyology, 20: 440-451.

G.H. Copp* and L. Vilizzi

Journal of Applied Ichthyology, 20: 440-451