Investing in the future of our rivers

There are many activities the Environment Agency undertakes with your rod licence money that are less well known. One of them is the ongoing programme of fish and habitat monitoring. It’s an exercise which provides nationwide data for future planning that will lead to better aquatic environments and ultimately, better angling opportunities. In 2021 there were 926 surveys carried out across England. We joined a fisheries team in Essex to find out more. 

The four-strong team is on a beautiful section of the River Pant near Saffron Walden. It’s situated on the edge of Constable Country and it feels like it. The sun is out, the clouds are high and the river is gently meandering and babbling its way through the silence.

It would be so easy to find a comfortable resting place and doze in the peaceful warmth, but the team is here to count fish and record important information about the river’s health. The type of species they find, their number and size and the ageing assessments conducted later by laboratory experts from the scale samples they collect, will all expose this river’s hidden secrets.

The plant life and the riverbed will also be monitored and this latest data from an annual survey that for the sake of the science always takes place on the same stretch of water, will add to fifteen years-worth of information that collectively details how the river is faring year-on-year. There’s no Hay Wain, easel or palette in sight, but Constable himself would be impressed by the scientific picture it all paints.

On arrival to the riverbank, the first thing I see is a stop net at the upstream end of a 200-metre stretch. Downstream, another net ensures that the section to be monitored will reflect its fish and invertebrate population at a measured moment in time.

The stop net

When a maximum of four electro-fishing passes have been made, the resulting data will have been gathered in identical fashion to every previous visit. Only nature will provide the variables.

Leading the team on today’s mission is the Environment Agency Fisheries Officer, Ben Norrington. “This is part of a national monitoring network,” says Ben. “Our rivers are surveyed for fish, macro-invertebrates, aquatic plants and water quality. From that data we can then look at long term trends in things like species decline and possible changes. That will indicate to us changes to either the environment, water chemistry or even land use. An exercise like this provides valuable baseline data that will support important decision making for future development.”

First pass..

Monitoring events such as this are conducted on various areas through a river’s course. This localised data can then be collated to create a general picture of the river’s overall health. On the Pant’s 30km length, six different locations will tell the wider story.

An example of this work in positive action is highlighted by an area of the river Stour at Dedham. Data showed that over a fifteen-year period species numbers were declining in a section where the river was dug out and, consequently, a uniform environment had been created. Once the problem was identified, the Fisheries team worked with the landowner to create a ‘scrape’ and gravels which introduced a more natural bend to work the flow. Since that work was done ten years ago, there has been a dramatic increase in the fish population.

After temporary capture, it’s time for data capture

Ben says: “The Colchester Piscatorial Society and Sudbury & Long Melford District Angling Society reported an increase in chub and bream numbers and there was a direct correlation between those reports and the habitat improvements that were derived from our original data sets and the mitigation work we did.”

Measured, scaled and ready for release.