In 2021, the first phase of a salmon smolt tracking project took place, with young salmon tagged and monitored as they travelled down the Ken/Dee River system in Galloway. This gave a lot of information about how Salmon navigate down the river, with 58% of the tagged salmon smolts making it to the Inner Estuary.
Building on the 2021 study, work has been underway in recent months to track the 2023 migration of smolts down the river, with a further 40 smolts tagged this year in advance of their trip downstream.
The work was led by Galloway Fisheries Trust, supported by Drax – the owners of the Galloway Hydro Scheme, The Galloway Glens Scheme, University of Glasgow, the Dee (Kirkcudbrightshire) District Salmon Fishery Board, Scottish Environment Protection Agency (SEPA) and Forestry & Land Scotland.
The journey of the tagged salmon is tracked using 33 receivers installed along the banks of the river, with data then analysed by the GFT and Glasgow University teams. Plans are afoot for this to be repeated in 2024, building an increasingly reliable and comprehensive data set.
The study focused on the capture of juvenile salmon at the point of smoltification (the point at which salmon start changing their physiology from being a freshwater fish and readying themselves to live in the marine environment) and tracking their movement down through the river system. Salmon smolts are relatively small and vulnerable to predation by larger fish such as pike, fish eating birds such as goosanders and mammals such as otters. The longer they spend on the migration the more vulnerable they are, this project looks at the mortality of the fish through the system and the length of time it took to undertake this journey, including past dams and other impoundments.
Forty fish were caught and tagged with small acoustic devices which sent a signal to receivers that were placed down the river system. Thirty three receivers were spread out from just below the Polharrow Burn (north of Dalry) all the way down to Kirkcudbright. A project of this nature is only possible as recent advances in technology have managed to ‘miniaturise’ transmitters and batteries so they do not influence the swimming ability of small fish like salmon smolts.
Salmon used to be abundant across the Solway and the River Dee was, arguably, one of the most productive of these rivers. Impoundments built on the river in the 1930s to harness energy had a large effect upon the ability of salmon to migrate through the system, both for smolts moving downstream and adult salmon ascending the river. Fish passage was considered during the construction of many of the dams with fish ladders built but understanding downstream migration of smolts has been more difficult.
A short, non-technical summary of the 2021 work has been published and is available here: https://gallowayglens.org/wp-content/uploads/2022/11/Kirkcudbrightshire-Dee-Salmon-Migration-Study-2021-summary.pdf. The 2023 works were also supported using funds from the Scottish Government’s Nature Restoration Fund.
Jamie Ribbens, Senior Biologist at Galloway Fisheries Trust, said:
“The 2021 study produced some very interesting results regarding how salmon smolts travel down the Dee system on their way to the estuary. This further study aims to understand in more detail how the fish are behaving under different conditions to investigate what could be done to ease their migration and thus maximise the numbers of smolts able to leave the Dee successfully. We need everyone working together to restore the salmon population in the Dee. It is good to be working with Glasgow University again on this important study and we appreciate that both DRAX and Galloway Glens have continued to supported the research.”
Martin McGhie, Drax’s Manager of the Galloway & Lanark Hydros, added:
“Gaining a better understanding of how species such as Salmon interact with our hydro-electric scheme is a key factor in helping us improve the ecology within the Ken-Dee catchment. The 2021 smolt tagging trials provided a fascinating insight into the journey the smolts take on their journey down through the river system. We are delighted to help fund further and expanded research which will hopefully build on the first trial and provide greater understanding of this process.”
Nick Chisholm, Galloway Glens Project Officer, added:
It’s great to see that a little bit of support from our National Lottery Funding and inspirational leadership from the Galloway Fisheries Trust allow us to unlock some of the salmon’s travel itinerary. The information that is gathered from this will be incredibly valuable and help the operator of the hydro scheme manage water flow for the salmon’s benefit. Dam fine work everyone!!
Jamie Ingall, Chairman of the Dee District Salmon Fishery Board, said:
“The initial smolt tracking project provided some important insights into the challenges faced by migrating salmon in the Dee (Kirkcudbrightshire) river system, however the data was limited and therefore could not be conclusive. This second phase will enable us to complete the picture and we are grateful to Drax and Galloway Glens for providing the necessary funding, as well as GFT and Glasgow University for their hard work in tagging and tracking the smolts in difficult conditions.”
Dr Scot Mathieson, Fish and Biodiversity Unit Manager at SEPA, said:
“SEPA continues to work closely with partners, fishery trusts and businesses in the catchment area to improve rivers and manage pressures on migratory fish. It was extremely interesting to see survival rates and the routes salmon smolts were taking through parts of the Galloway Hydro Scheme following the first tracking study on the Dee in 2021, and we are encouraged that this work is set to continue to build a more robust picture. The data and information this study provides will be a valuable, additional resource for exploring options to ease smolt migration downstream.”
The Galloway Fisheries Trust is a charitable trust whose aims are to restore and maintain aquatic biodiversity, particularly native fish, in Galloway by means of practical, responsible and sustainable approaches to land, water and fishery management, based on sound science, for the benefit of the community as a whole. More info: https://www.gallowayfisheriestrust.org/.
The Galloway Glens is a 5-year suite of projects aimed at connecting people with their heritage, boosting the local economy and supporting sustainable, thriving communities. It is an initiative of Dumfries & Galloway Council’s Environment Team funded by a range of partners including the National Lottery Heritage Fund and Drax, the owner of the Galloway Hydro Scheme. More info: www.gallowayglens.org.
Drax Group acquired the historic Galloway Hydro Scheme in 2019 as part of a portfolio of important renewable, low carbon and flexible power generation assets. The company pledged £100,000 over four years to support community initiatives in the Galloway Glens region as part of its efforts to support those living in the areas in which it operates. For more information visit www.drax.com
About the Dee (Kirkcudbrightshire) District Salmon Fishery Board:
Salmon fishing rights in Scotland are private heritable titles that are registered separately from land. The cost of the local administration, protection and improvement of salmon fisheries is privately financed by the fishery proprietors via the District Salmon Fishery Boards (DSFB). The DSFBs finance their work by levying a rate on the salmon fishery owners in the district, whilst elected representatives of those owners provide the core of the membership of the Board. The DSFBs work to conserve Scotland’s valuable and iconic wild salmon and freshwater fish and fisheries and the aquatic environment on which they depend, often with limited funding. The Kirkcudbrightshire Dee has the largest catchment of all the Galloway river systems and is also the most heavily modified, therefore it faces unique challenges among Scottish rivers.