ISSN:
1095-8649
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Precise homing of 24 brook charr Salvelinus fontinalis (157–215 mm LF), displaced from their site of capture in a natural stream, was rare both in fish displaced upstream and those displaced downstream. Most fish settled in preferred habitats (pool or glide) away from their home site and showed restricted movement up to the pre-spawning period. Partial return responses, however, were stronger in fish displaced downstream than in fish displaced upstream. Most fish displaced downstream showed directional upstream movement soon after displacement, whereas fish displaced upstream did not show directional upstream movement, suggesting that it is primarily olfactory cues from upstream locations, and not positive rheotaxis, which mediate the return response. Homing success was unrelated to distance of displacement, body size, or population density in the home site, but daily mobility increased with body size for fish displaced downstream. There was no evidence of switching between specific areas between night and day, nor of differences between daytime and night-time mobility, suggesting that diel movement cycles did not bias the evaluation of homing success. Site attachment in stream-dwelling brook charr may be characterized as persistent (undisturbed fish remain stationary over long periods), but readily disrupted by involuntary displacement.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1095-8649.2001.tb00166.x
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