The River Derwent in Derbyshire was heavily used and altered during the Industrial Revolution. It powered the mills of the leading entrepreneurs of that time, Richard Arkwright and Jedediah Strutt.
There were two unforeseen legacies of this development - one was a deterioration in water quality and the other was that the installation of weirs to generate power for the mills hindered the migration of salmon to their original spawning grounds.
The Derwent was once home to a thriving salmon population - they were plentiful as a food source and were seen as a species of no great concern. Consequently salmon disappeared from the Derwent, particularly in the upper reaches.
Through effective partnership working we have installed fish passes at Borrowash and Darley Abbey. These have opened up the Derwent to migration as far as Duffield. Commercial development of hydropower has also led to a fish pass at Longbridge Weir.
A programme of electric fishing surveys has been set up along the Derwent to track the success of the salmon and to give an indication of their numbers. These are targeted at sites offering favourable habitat to maximise the likelihood of catching salmon parr. There is evidence that the population is successfully migrating and the habitat continues to be suitable for spawning.
We opened the fish pass at Darley Abbey in autumn 2013, so seeing salmon in Duffield in 2014 suggests that adults had migrated through the pass and spawned that winter. Scales collected from the salmon support this, confirming that the parr were in the first year of their life and growing at a fast rate. The 2015 survey showed an improvement from previous years and anglers have also reported the majestic sight of salmon jumping in the Derwent.
Historically salmon were once well established within the River Derwent. Through our work with partners, water quality and habitat conditions have continued to improve. Although we’re constantly faced with new challenges, by addressing barriers to migration and with a renewed focus on salmon it will help to see salmon return to the Derwent in good numbers in the future.
Lizzie Brailsford is a Fisheries Officer at the Environment Agency covering Derbyshire, Nottinghamshire and Leicestershire.
11 comments
Comment by Naomi Ibbetson posted on
Thank you for the commentary, I do hope you will find a way of breaking the barriers that also seem to influence much of our wild stock such as eels and others. It is good to hear that water quality is improving and fish are thriving (they are a good indicator to water quality).
Comment by john roberts posted on
The weirs need to be removed. I recently saw a flyer advocating Weir Watch, supported by the Environment Agency. The public are being drafted in to feed back on the state of weirs on the Derwent so they can be repaired. Fish passes are not good enough. The river is ruined for many miles due to impoundment from weirs.
Comment by jamesphutton@hotmail.com posted on
I have had a confirmed report of salmon parr in the Derbyshire wye at Rowsley so this must mean that the salmon are getting right up past matlock and no doubt beyond, in the 1970s I heard of a salmon at calver mill above Baslow.
Comment by jamesphutton@hotmail.com posted on
If you want a salmon watcher ask me I will. Volunteer I already watch the mersey salmon
Comment by J ALexandra posted on
Large dead salmon , over 2 ft seen on Belper weir this week. It looked as if something had been feeding on it. Have taken photo and contacted wildlife trust. Wonder if the size suggests that it has been dropped into the river by a predator or human .
Comment by kathrynbooth posted on
Thanks for reporting this, we were able to visit the site and confirmed the presence of a large adult (male) salmon. This was probably a result of nature taking its course, possibly as you described. Despite the few setbacks that nature throws our way, the salmon population we are recording are going from strength to strength and it is looking positive for the future.
Comment by kathrynbooth posted on
Ales, Since the Industrial revolution, Salmon have been virtually absent from the Derbyshire Derwent catchment. The construction of many of weirs and poor water quality during this period in history has led to only a handful of Salmon sightings in recent decades. Fast forward to the present day and the situation is much more positive. Adult Salmon are now making the gruelling 150 mile journey from the sea via the River Humber and Trent to return to the Derbyshire Derwent, and are spawning year on year. The monitoring we undertook in 2016 has shown an 11-fold increase in the numbers of juvenile Salmon since 2013 at our survey site in Duffield, Derbyshire.
Over the last 5 years the Environment Agency has worked with partners and developers to enable the construction of fish passes at Borrowash, Longbridge and Darley Abbey weirs. The construction of these fish passes has now enabled more adult salmon to travel further up the river and access greater and more varied areas of habitat helping to ensure the salmon have the right conditions to spawn, shelter and feed. Watching salmon jumping majestically at weirs is an incredible sight, yet this is a clear indication that they cannot pass the barrier easily. Typically, these salmon often have to compete for suitable spawning areas downstream of the barrier or spawn in areas that are less favourable, reducing the likelihood of these fantastic fish contributing to the next generation of River Derwent salmon stock. Weirs not only stop fish migrating, but trap fish spawning gravels and create ponded areas upstream which are not suitable for riverine fish species.
In December 2016 we received a report from an angler who had seen a large dead salmon on Belper Masson Mill weir, Derbyshire. Thanks to the report, we were able visit the site and confirm the presence of a large adult cock (male) salmon. Many challenges remain, but we are committed to ensure that salmon numbers continue to increase within the catchment by working with partners to enable fish passage on the remaining barriers and to improve the quality of river habitats for this fascinating species.
Comment by Cocopops posted on
if the fish you seen was in january well its most likely a "Kelt" a fish that has spawned as in most rivers in january they us hardly and new fresh fish starting to run and when they is its usually on the lower ends of tidal limits and just into freshwater,kelts nearly always die esp cock fish (males) they the ones that die the most out of the two sexes,females can get back down to see after spawning more readily than males.now im not sure where you seen this fish,and how far up the river system it is,but IMO if yer not directly near tidal water or tidal ends into freshwater,its most liley a kelt,as by january they have sually done there thang! spawning takes place on the eastern side of england from late october to december time,then thast usualy it,kelts look thing compared to a fresh run fish,and can have large or small white spots which is a fungal growth as after spawning they are exhausted and have been living only on body fats for nearly a yr for some of the fish,so they are very vulnrable to diseases,but oin general the white fungal growths they get are usually a dead giveaway esp this easrly in the yr for up river
Comment by David posted on
Is there any plan for fish passes to allow migration upstream of duffield?
Comment by Bill Sowebutts posted on
What about the weir at Ambergate ...this is the biggest barrier...is there a fish pass through this yet....because without that anything you report on salmon is token
Comment by kathrynbooth posted on
Hello Bill
There are many barriers to salmon migration remaining on the river Derwent, some of these may be passable at higher flow conditions, while others such as the Ambergate weir you mentioned are likely to be impassable to salmon under most conditions. We have successfully worked with partners to build several fish passes on major weirs on the lower Derwent, this has allowed salmon to access suitable spawning habitat and juvenile numbers have increased year on year since 2013. We have recently discovered that salmon distribution within the catchment is expanding, having recorded juveniles in the river Ecclesbourne and as far upstream as Belper on the river Derwent. Our ambition is to enable salmon to migrate throughout the Derwent catchment, there are many challenges to achieve this, but we are continuing to with partners to find solutions on the remaining weirs.
Regards Amy