Conserving, restoring and enhancing the water environment and habitats of the River Dee

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1 May 2016 Conserving, restoring and enhancing the water environment and habitats of the River Dee Report on World Fish Migration Day event and Salmon Stock update Big Dee Day The Invasion Launch Friday June 24 th Catchment Advisors Work to reduce Pesticide Update on Partnership working to reduce diffuse rural pollution Our search for future funding World fish Migration Day Event held at Chester Weir Salmon Trap on May 21 st The full Dee Stock Assessment Report for 2015 has now been released and confirms that both the declared rod catch of Dee Salmon (233) and run size (3,051) have fallen to their lowest ever recorded levels.

2 In addition, the size of our returning salmon continues to decline. In particular, it seems that 1 sea winter salmon (grilse) numbers are falling, and salmon are having to stay at sea longer, becoming 2 sea winter, or more, salmon, to attain a more appropriate size for spawning. This is probably due to reduced food availability on the high seas feeding grounds, and is a trend noted in all UK Rivers. More encouragingly, sea trout numbers are improving, particularly for smaller fish (Whitling). As seatrout do not migrate far to sea, this may be due to an improvement in local marine environment. It has been suggested that this is a result the profusion of local offshore wind farms. Each wind turbine base provides a reef like environment providing enhanced habitat for all sorts of fish, and marine life which could lead to an increased food source for sea trout. The presence of wind farms also reduces marine fishing pressure. A more pessimistic view is that the sea trout are thriving by filling a gap left by declining salmon numbers. Floy tag inserted behind dorsal fin of a salmon (above) and VI -visible implant tag inserted behind eye of a seatrout, Against this background National Resources Wales combined with the Welsh Dee Trust and the North Wales Wildlife Trust to hold an event on World Fish Migration Day-May 21 st -at The Fish Trap on Chester Weir. This was an opportunity to showcase the important work done by Richard Cove and Ian Davidson of NRW, in tagging salmon at the trap and explaining the vital work of the Dee Stock Assessment programme. Welsh Dee Trust exhibited examples of work done to improve fish passage within the Dee Catchment and work to improve riparian and instream habit. North Wales Wildlife trust presented details of the Dee Invasive Non Native Species project, which improves habitat by dealing with Invasive weeds such as Himalayan Balsam and Japanese knotweed as well as watching out for invasive animals such as Chinese Mitten crab and Signal Crayfish. After a poor start to salmon trapping up to the end of April, numbers have suddenly increased in the last few weeks, giving the best trap catch figures in May, for the last ten years. Hence delighted members of the public could witness Richard tagging both salmon and seatrout-a really important demonstration, particularly to young children, of the presence and importance of this largely unseen species that swims up our river Dee. A typical comment was I ve lived in Chester for 30 years and didn t even know there were salmon in the Dee! This shows we need to build on this success and hold similar future events to engage the general public in the presence and plight of our salmon.

3 The Launch of this year s Big Dee Day The Invasion event takes place on Friday 24 th June at The Boat Inn, Erbistock. 9:30 to 11:am, followed by a demonstration of weed control on the river bank. There will then follow a programme of events throughout July. If you wish to get involved, please contact Mark Hudson (MarkHudson@wildlifetrustswales.org) For more details or visit the project website ( Himalayan Balsam and Rust Fungus Scientists at the Centre for Agriculture and Biosciences International (CABI) has found a natural predator of the Himalayan balsam. In the plants natural range (the foothills of the Himalayas, India and Pakistan), a natural occurring fungus keeps the plant in check, ensuring that the plant does not aggressively colonise river banks and damp woodlands. This fungus is known as a rust fungus (for the more scientific Puccinia komarovii var. glanduliferae), and is a five spore staged rust fungus which infects the stem and leaves of Himalayan balsam throughout the growing season Strictly following internationally recognised testing procedures, the rust was tested (in quarantined conditions) on 84 plant species (including some hybrids). The scientists we able to prove that the all spore stages of the rust are only specific to Himalayan balsam only. Contaminated plants, were planted amongst uncontaminated plants, with the aim of letting the rust spores spread naturally. Initially (2014) the fungus was released at three authorised locations, and then in 2015 at a further 25 sites. These trials found that the fungus spread successfully, albeit at better rates at some sites. In 2016, the field tests will continue at the 25 sites, and some more in Wales. CABI anticipate that a full release program could occur as early as 2017 once the host-pathogen system in field conditions in the UK is better understood, and release strategies refined. Although, as yet no details have been given about how the plants will be distributed. Meanwhile we have be advised, that we should continue with balsam bashing, otherwise the amount of balsam on our river banks will be out of control, and in much larger quantities. Glyphosate update You may have read in the press about the future possible banning of glyphosate sale to the general public because of the perceived carcinogenic risk. This will not affect its availability to our trained volunteers, who will continue to use spraying to control the Japanese Knotweed within the Dee Catchment. Indeed, the DINNSP has recently obtained permission to extend spraying to cover earlier in the year. Although Glyphosate is most effective when applied during the flowering period in August -October, often it is benficial to spray small emerging knotweed plants in May. These are often shrubby stunted plants that may remain after spraying during the previous year. If left until September, they may be difficult to find as they are hidden by other plants-usually Himalayan Balsam!

4 . Emergency Hotline Chemcatcher retrieved form Pulford Brook after 14days in position. And one from Wyche/ Worthenbury after the same period Catchment Advisor Activity Gareth and David, our catchment advisors, have been busy in the Upper and Middle Dee Catchments advancing measures to reduce inappropriate pesticide usage. They have established steering groups, including landowners, farmers, regulators, farming unions and other stakeholders to address the problem. As both have a farming background, this has helped with establishing the necessary contacts and networks to facilitate this work. A characterisation of the catchment has been produced, detailing types of agricultural land and what crops are mainly grown and what type of pesticides are likely to be used in each area. They have established schemes for farmers to loan weed wiping equipment. This markedly reduces the application of herbicide in comparison to spraying. Within the Alyn and Alwen sub catchments, they have arranged for farmers to have MOTs on their spraying equipment to ensure it is operating efficiently. Other initiatives include a pesticide amnesty by which unwanted or unidentified, possibly now prohibited pesticides, are collected and disposed of, reducing the risk of them being inappropriately disposed of and leaching into the Dee Catchment. They are also publicising a scheme to substitute ferric based slug based for metaldehyde compounds which are extremely difficult to remove from the Dee drinking water supplies. In addition, they are deploying Chemcatchers all over the Dee catchment. These devices are left in situ for 14 days and measure the amount of various pesticides leaching into that part of the Catchment (see photos above). The subsequent reduction in pesticides will have a beneficial effect on the native flora and fauna as well as water quality, leading to more insects on our rivers which, in turn, increases the food supply for our fish.

5 Cattle poaching noted on banks of river Alyn during recent survey. This leads to increased siltation within the river and requires bankside fencing Middle Dee Partnership Working Following completion of diffuse pollution projects on the Wych and Worthenbury, and Aldford Brook, Mark Pierce, project officer is turning his attention to advancing the planned survey of the River Alyn from Mold down to the confluence with the Dee. Already, trained volunteers have surveyed certain sections and catalogued problems with water quality, invasive species and habitat degradation due to stock poaching. Schemes to address these issues, are being drawn up and can be advanced as funding sources are identified. The Search for future funding Without funding, much of our good work will grind to a halt. It looks certain that some Defra funding will be made available for partners to continue diffuse pollution work on the Aldford Brook. Funding streams such as Big Lottery and Heritage landscape partnership funding have been explored, but often do not suit river based schemes. The Welsh Dee Trust has recently submitted two bids to the Welsh Government Sustainable Management Scheme. One, to help expand our catchment advisor work with farmers and landowners to counter rural pollution. The other was submitted in conjunction with the North Wales Wildlife Trust to help river restoration and invasive species management with the aim of improving fishing and opening new angling opportunities to the public, particularly visitors, thereby contributing to the local economy. We will learn if we have been successful in early July. For further information contact: Name Richard Lucas Welsh Dee Trust rmlukas@msn.com Emergency Hotline Emergency Hotline