Lyons Bridge to Ennis Lake

From Lyons Bridge to Valley Garden I have 8 samples, (149, 118, 150, 280, 10, 61, 153 and 273). This is a long section of river with more gradual transitions than above. Aquatic oligochaetes become less abundant and more localized. Tubifex is present throughout this reach, but it is less generally distributed. It no longer much occupies sand and gravel substrates, but is increasing restricted to the mud bars. For example, the Ennis fishing access site is very poor Tubifex collecting, but the Valley Garden access site is very good Tubifex collecting. This may be a sign of a recovering community that displaces Tubifex from the more desirable habitats. The mud bars themselves become more common moving downstream, so total Tubifex remains fairly high. Rhyacodrilus is much less abundant and Ilyodrilus templetoni re-enters the community, both signs of the changing substrates and temperatures.

Aquatic Oligochaete species list

5 JAN 1997 D.L. Gustafson
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