Hi Susan - it's still relatively early in the season for river dragonflies, but I'm not surprised there seem fewer than normal. With the impact of the denudation of catchments by the bushfires, and subsequent two years of sometimes very heavy rainfall, the heavy flows in creeks and rivers have had a major impact on re-engineering the nature of the riverbeds. Many look scoured, and there are sometimes new deposits in different places. It must surely also have had an impact on the survival and numbers of odonates this season. It would be really great if you can keep this in mind when recording and submitting records, perhaps with an accompanying note of you thoughts on the matter for each situation.
No worries. And thanks for your comments - I wasn't aware it was early in the season as it was really very warm on the walk although of course today it's really rather cold. Almost Melbourne weather