Research launched to discover Dipper population and what this means for river health

A University of Gloucestershire expert in ecological research is inviting local communities to contribute to a survey monitoring the population of a bird species and river health in the Stroud Valleys.

Dr Mark O’Connell, Senior Lecturer in Practical Ecology from the University’s School of Education and Science, will use findings from the Stroud Valleys Dipper Project to assess river health and provide solutions to declining Dipper populations.

Dippers (main image) are highly sensitive to changes in water acidity and pollution, and are therefore an important bio monitoring species for freshwater habitats.

Dr Connell said: “The River Frome and its tributaries are over 90km in length and there is a lot of development in the catchment. We need to know if that change is going to damage biodiversity.

“It is impossible to monitor everything, so instead we use bioindicators, and an excellent indicator of river health is the Dipper.

“Dippers feed on water invertebrates, and pollution can affect their populations. This in turn causes changes in Dippers’ breeding outputs (number of eggs and successful chicks). A healthy river is indicated by a healthy Dipper population.

“One of the aims of the 2025 pilot project is to set a baseline for Dipper populations in the Stroud Valleys because you’ve then got something to measure change against.”

The research comes as the planet is experiencing the most severe biodiversity crisis in history, causing significant wildlife loss, including a decline in Dipper populations across the UK.

The International Union for Conservation of Nature (ICUN) Red List allocates species to a particular extinction risk level: green (the species is doing well), amber (there is cause for concern), and red (the species is endangered). Dippers are now amber listed due to a 39% decline in the UK since 1995.

Dr O’Connell said: “Dippers are sensitive to agricultural intensification and chemical run-off in river systems – for example, the overuse of fertilisers.

“There’s also the loss of riverine habitat due to urbanisation and increased disturbance. So, whatever is going on in the catchment is reflected in the health of the river.”

Research providing practical solutions

Although Dipper populations are declining, Dr Connell said there was hope of reversing it and that research would lead to practical conservation.

Dr O’Connell said: “We are providing the evidence upon which action can be taken. We’re taking a complicated environmental situation and coming up with practical solutions.”

Describing how climate change was affecting climate health and Dipper populations, Dr O’Connell said: “If you take average monthly rainfall compared to 30 years ago, there’s not actually much difference.

“What is different is that the same amount of water tends to fall in a much shorter period (pulses). This all ends up in the river, which flushes out the invertebrates, impacting the Dippers’ natural food source.

“The way we reverse that is by slowing down the water across the wider catchment. We can put the bends back in the river and implement leaky dams, which slow down the river.

“Changes also need to be made to agricultural practices, making them less intense so that there are fewer pesticides and less fertiliser being used, resulting in less pollution in rivers.”

Relying on the involvement of the public, the Stroud Valleys Research Project has already caught the attention of local communities across the Five Valleys.

Dr O’Connell said: “There is a surveyor’s survey that already has over 50 members of the public covering nearly 30 miles of the river. The volunteers carry out monthly surveys and record their sightings on the project website. Members of the public can also send in their sightings whenever they see Dippers on the river.

“We all have ownership of our local environment and therefore a joint responsibility to look after it. We are the guardians of the river and the time to take action is now.”

Visit the Stroud Valleys Dipper Project website where you can find more information about Dr O’Connell’s research and report a Dipper sighting.

You can also sign-up to become an Official Dipper Surveyor by emailing Dr O’Connell at [email protected]