This year’s trapping programme, on both the Beltie and Sheeoch burns, is beginning to wind down as the run of salmon smolts nears an end for this year. Our sea trout smolts are continuing to migrate downstream and have recently formed the bulk of the fish in the traps. The traps will continue to operate as long as fish are migrating.
The production of smolts is of major importance to our fishery. Recent poor seasons have made us concerned about the fate of our smolts as they begin their long journey from the river through the harbour and estuary to the open sea. This early part of the smolts’ journey has been shown to result in high mortality rates in other systems and it is crucial we discover what is happening on our own doorstep. There are many theories about the condition of the Dee juvenile population and over the next three years our project will produce hard facts and inform decision making, particularly in regard to predation.
This first year of the project has gone well. We had all the usual hiccups associated with a major project, but the team overcame these and have been encouraged by the early results.
Dr Lorraine Hawkins has led the team during an intensive period of work, which has been ongoing 7 days a week since March, and is pleased with how the project has gone so far.
“This year we tagged 50 smolts from the Sheeoch and Beltie burns. Last week, we completed the first download from the receivers we have placed in the lower river and harbour. So far, the receiver at Lower Crathes has picked up 31 of the tagged smolts and one in the lower harbour has picked up 34 of the smolts. It is great news. Firstly, that the smolts we detected have survived the surgical tagging procedure and secondly, the technology is working in the very difficult – and noisy - environment of Aberdeen Harbour. The receivers are picking up uniquely coded tags in the Harbour that are the size of a tic-tac, so I am relieved it has all gone so well.”
We will have all the data from the loggers by the end of June and will be able to determine the movements of individual fish. We will tag another 100 smolts in 2017 and again in 2018 and this will give us robust information about how our smolts fare during the early phase of their migration. Of particular interest is the impact of predation. If there is a major issue with predators, we will be able to demonstrate this with hard evidence.
Finally as part of the work we are doing with BBC Landward this year a short piece will be aired on the evening of June 3rd as Dougie Vipond visits one of the traps and also a receiver in the harbour to discuss the tracking programme with Lorraine and the team.