Volume of trees cut for WOODCHIP as at end of February was approximately 40,000m3 and only 10,000m3 for sawlog

see www.baddevelopers.green.net.au

CONCLUSIONS

1. The Gellibrand Catchment has a high diversity of aquatic macro invertebrates compared to other basins monitored by WATER ECOscience across Victoria as part of the MRHI program.

2. The catchment has a highly variable flow and low Summer flows were acknowledged as contributing to the decrease in Autumn invertebrate species richness.

3. Pool habitats are the most significant habitat in the Gellibrand catchment due the reduced abundance of riffle habitats throughout the catchment. Also, the inundation of the riparian zone from winter flows is essential for the increase in breeding habitat.

4. Riffle habitats are reduced in size with low summer flows and invertebrate diversity in riffles may be reduced as a consequence.

5. Water quality throughout the catchment was generally seen to be of a high quality although nutrient levels were identified as impacting upon river health in the lower and mid catchments. Nutrient levels were identified as the cause of extensive algal growth in Love Creek and plant growth at the Gellibrand River downstream of dam site GSA.

6. Macroinvertebrate species richness generally declined in a longitudinal pattern, from headwater streams to lowland rivers, which is consistent with other macroinvertebrate surveys.

7. The major impacts upon the macroinvertebrate fauna were identified as the loss of instream habitat, removal of riparian vegetation, river regulation and the increase of sedimentation, nutrient loads and turbidity in high flows. Loss of instream habitat appears to be the most critical factor in the Gellibrand Catchment and possible remedial actions include replacement of native riparian vegetation, controlling stock access and bank stabilisation.

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Biological Monitoring in the Gellibrand Catchment Feb 1998 Cameron and Vertessy Page 46