Riverfly Census

understanding and improving water quality in UK rivers

Insects (which make up 97% of all animal species) have declined 59% since 1970

This is hugely problematic for wild salmon & trout, who need need healthy water environments to thrive.

But why are aquatic insects so important?

Foundation of life

Small but all-sustaining, insects are food for our wild fish, birds and mammals. Without invertebrates, the food web would collapse.

Long-term health indicators

As nymphs, insects are constantly exposed to the water, sometimes for years. A water sample would only give you river health information for a single point in time.

Excellent storytellers

Every invertebrate is unique, thriving in a specific set of conditions. The types of bugs present and absent from a sample indicate what pressures a river may be experiencing.

We frequently talk about missing flylife and lack of fish compared to the 'good old days', but anecdotal evidence like this has little weight in environmental decision making.

The Riverfly Census was our way of collecting much needed high-resolution, scientifically robust data about water quality in our rivers.  

Riverfly Census

Across several iconic rivers, we have professionally sampled and analysed invertebrate life to understand the health of the river and the issues which need tackling.  

We use this professional, scientific evidence to campaign for improved protection of our wild waters.

SCOPE

The Riverfly Census has spanned three years. It began in 2015, with 12 rivers across England. Multiple sample sites were carefully selected on each river.

SAMPLE

Kick sweep sampling was completed in spring and autumn to EA guidelines, at all sample sites. Sampling and species-level identification were carried out independently by professional external consultants, Aquascience Consultancy Ltd.

STUDY

Species presence/absence data was inputted into Aquascience’s biometric calculator to obtain scores against key stress types. The data was then evaluated in a whole catchment context to pinpoint likely suspects contributing to river deterioration.

MAKE A STAND

The data was compiled, and is being reported to stakeholders and policy makers, to improve management and conservation of our rivers.

How do we sample?

Here’s how we use insect samples to find out what’s going on:

Census Process Image 1

A 3-minute kick sweep sample is taken at a river site making sure to survey all the different habitat types.

Census Process Image 2

The sample is pickled using a special alcohol. This preserves the insects so that counting and identification can be done at a laboratory.

Census Process Image 3

The sample is sorted into groups by an expert and the insects are identified to species level using a microscope.

Census Process Image 4

The list of species present is put into a unique scientific calculator. This gives a value for how much the site is being impacted by five key stressors.

What have we found?

The Riverfly Census is producing two main outputs:

A national baseline

Watch this space, we are working hard to generate a national summary of our findings, using the data to drive national policy improvements and influence more robust baselines.

Click below to read our national conclusions & policy recommendations:

Screenshot 2019-05-29 at 10.41.00

Evidence to drive local improvement

In progress, we are currently compiling local information and delivering our results to relevant policy makers and stakeholders. See our map below and keep an eye on our news for release of local reports.

Use the map below to find our local Riverfly Census reports:

The Riverfly Census is evolving...

We see a future where all rivers in the UK have intelligent monitoring and an accurate baseline for measuring change, but we cannot do this without your help.

If you want to be involved in smarter monitoring that achieves real results in your river please visit SmartRivers.

Latest Riverfly Census News

SmartRivers is delivering results

12/09/2019
The hot dry summer has exposed the stress our rivers are under Nick Measham, Deputy CEO, S&TC To view the full interview click HERE The hot dry summer has exposed the stress our rivers are under – particularly in Southern chalkstreams where algal growth and sediment is choking life to a seemingly unprecedented extent. Once […] Read More

Discharges from salad washing – Update

31/07/2019
Salad washing on the Upper Itchen: A local problem with national significance… Nick Measham , Deputy CEO, S&TC writes……. S&TC’s battle to stop Bakkavör discharging pesticides and chlorinated plant-cleaning chemicals from its salad washing activities is achieving increased environmental protection, and not just for the Upper Itchen. [Previously covered by BBC Countryfile] As a result […] Read More

Chalk streams debated in parliament

31/07/2019
We always intended the Riverfly Census to be a lobbying document as well as reporting on the science, and this has been an excellent first political outing for it. Paul Knight, CEO, S&TC In a speech during a House of Commons debate on “Degraded chalk stream environments”, Richard Benyon MP cited evidence from S&TC’s ground […] Read More

Dear Phil, Thank you so much!

26/06/2019
What can we say other than a huge THANK YOU!! Phil Chessum took on the challenge of running the Race to The King ultramarathon to raise money for S&TC. An exhausting 52.4 mile slog across the South Downs. Completing the course in a very respectable 10 hours 26 minutes and finishing 71st out of 750 competitors, Phil’s feet seemed to […] Read More

Response to Southern Water Fine

25/06/2019
  Ofwat has imposed the biggest fine ever on a water company for “significant breaches of its licence conditions and its statutory duties.” Southern Water has been fined £37.7m, but this has been reduced to £3m because the company has undertaken to pay customers some £123m over the next five years. Ofwat states in its report: […] Read More

Bakkavör Alresford Salads Impacting Upper Itchen

17/06/2019
  Sewage and pesticides from a salad washing factory owned by Bakkavör Group Plc may present a serious threat to aquatic invertebrate life on a highly protected English chalkstream.  The Environment Agency’s response to a formal notification of environmental damage made by S&TC in June 2018, pursuant to the Environmental Liability Directive, confirms the wild […] Read More

Profits And Pollution

29/05/2019
“S&TC has for a long time questioned the English water companies over their abstraction policies, especially in water-scarce, aquifer-fed regions, but now it appears that other sectors of the industry are under scrutiny.” Paul Knight, CEO Salmon & Trout Conservation writes….. Carry out the basic duties In the Financial Times recently, it was reported that […] Read More

The Riverfly Census: Launch

29/05/2019
“If you do nothing else this month, read the Riverfly Census report which got its first airing at a mid-May reception in London.” Nick Mesham, Deputy CEO, Salmon & Trout Conservation To download the full report: CLICK HERE ‎ Once upon a time, industry was poisoning the nation’s life-blood rivers, but the story nowadays is all […] Read More

SmartRivers Update – June 2019

29/05/2019
May saw the initiation of another one of our SmartRivers pilot hubs. We are very happy to be adding two chalkstreams – the Avon and the Wylye – to the SmartRivers family, thanks to Wiltshire Fisheries Association. Taking river guardianship into our own hands For all rivers being added to SmartRivers, a professional scientist has […] Read More

The Riverfly Census: Full Report

15/05/2019
“The Riverfly Census Report has been central to S&TC’s work for the past three years and coincides with the United Nations’ recent statement on the catastrophic state of the global environment. The results should worry everyone. Our message is simple; unless there is radical change our rivers will soon become lifeless.  With ever increasing mainstream public […] Read More

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