The river Great Ouse running through Buckingham’s town centre is showing very promising signs of recovery, thanks to regular river invertebrate (riverfly) monitoring, now taking place by local River Wardens!

The River Warden group (initially formed in late 2019), in response to the devastating pollution incident in 2018 with the support from Buckingham Town Council and the Environment Agency, have now been trained to take monthly samples of the river. The training occurred on 18^th July 2021, by an accredited Riverfly Training Instructor:

“It was brilliant to deliver a Riverfly Partnership Workshop in Chandos Park on Sunday and to be able to support the hugely valuable River warden scheme following your devastating pollution incident, the interest in the river and awareness of the park visitors was really inspiring.” - Ian Hawkins, East Anglian Riverfly Hub Coordinator

This training as part of the Anglers’ Riverfly Monitoring Initiative (ARMI) which is hosted by the Freshwater Biological Association (FBA), allows these newly trained Riverfly Monitors to score the health of the river, based on the presence and abundance of specific riverfly target groups. This ultimately aims to improve existing river monitoring in the local area and help detect and deter future pollution incidents.

"I thoroughly enjoyed the Riverfly monitoring training session, after studying the theory it was lovely to put it into practice.  The session involved taking samples from the river, identifying and separating the indicator species and finally counting them before returning them to the river." – Ruth Newell (River Warden)

 Riverflies consist of caddisflies, stoneflies and mayflies which live most of their lives as larvae on the bed of rivers, emerging as short-lived adult flies. Acting as a biological indicators of river health, and being very sensitive or even intolerant of pollution, these invertebrates respond very quickly to pollution. Through this regular monitoring, trigger levels can be set, so that if they were to fall below the set threshold for this site, it would raise the alert of poor water quality.

During the training workshops, six of the eight indicator target groups were found in good numbers, demonstrating very promising river health and recovery. These included excellent numbers of olives (Baetidae), which are a family of small fast-swimming mayfly larvae, often called ‘agile darters’, along with abundant Gammarus (freshwater shrimp). There were decent numbers of larger burrowing mayflies (Ephemeridae) which are powerful 3-tailed swimmers that burrow into silt, good numbers of cased caddisfly larvae (Tricoptera), which make tube-like cases from stones, grains and plant material, along with the occasional caseless caddis.

Of greatest interest though were the several blue winged olives found (Ephemerellidae), which are particularly sensitive to pollution, demonstrating that the river health is surprisingly good. A stone loach fish was also recorded which was a species not re-stocked by the Environment Agency since the pollution event.

“This is certainly very encouraging news indeed, that given the chance, the river system can be quite resilient and is able to bounce back to its former health following such a catastrophic pollution incident just three years prior. Presence of all these invertebrates will not only provide food for fish, mammals, birds, and bats, but will also reassure the residents of Buckingham that their local river is healthy and safe.” - River Warden Coordinator, Ruth Coxon from The Conservation Volunteers (TCV).

The Buckingham & Gawcott Charitable Trust have made this training possible, by funding the riverfly training workshops and equipment needed for continued monitoring.

A public presentation of the cheque was made by Trust Chairman Councillor Robin Stuchbury during the morning training session on Sunday 18th July at Chandos Park, which turned out to be one of the hottest days of the year so far.

“It was great to see such interest from the public also enjoying the space at Chandos park with many passers-by, including young children, often showing an interest in the group’s activities, and asking what we were doing. Most were aware of the pollution incident 3 years ago and were pleased to hear that the river was recovering well.” - River Warden Coordinator, Ruth Coxon

Now trained up, the River Warden Group will be able to conduct monthly riverfly monitoring and input the results as publicly accessible data to the Riverfly Partnership’s online database. Monitoring efforts here will hopefully deter future acts of pollution and keep the river clean, healthy and thriving with wildlife for years to come.

“Riverfly sampling is an incredibly important tool in monitoring the river for water quality and in these days when the Environment Agency are under financial pressure with reduced ability to monitor water quality as they would have in the past. It is local volunteers who are needed to fill that space. If anyone is interested in joining I am sure that Ruth Coxon would welcome them and hopefully a number of further sampling sites can be created and monitored along the river to demonstrate the remarkable resilience and recovery of the river and to keep watch and report quickly any future incident of pollution.” Ian Hawkins, East Anglian Riverfly Hub Coordinator.

The River Warden group look forward to seeing how the health of the river improves. For more information about The Conservation Volunteers and the wide range of projects occurring nationally, please visit: https://www.tcv.org.uk.