In celebration of ZSL’s citizen science volunteers on the Thames

World volunteering week is upon us, and with it an opportunity to reflect on the wonderful volunteer support that ZSL receives for projects on London’s rivers. Each year the work of our team is bolstered by over 250 citizen science volunteers. While a good cross section of Londoners join us for each project, there is a bias towards retired people and students looking for experience to increase job prospects (it works!). However, in common with other environmental NGO’s, the ethnicity of our volunteers doesn’t mirror the rich ethnic diversity of London. With the help of City Bridge Trust, we will be looking to address this issue over the next two years. What our army of helpers have in common is a passion for aquatic wildlife and a desire to see their local environment improved and I consider myself enormously lucky to be working alongside them.

Photo of a group of volunteers by the side of a river next to a village green

Some of our volunteers have stuck with us since 2011, when we first started incorporating citizen science into our Thames projects, specifically our monitoring of the Critically Endangered European eel’s upstream migration. This project, with thanks to the help of over 100 volunteers each year, has developed into the most extensive eel monitoring project in a single river catchment in the UK and provides vital data on recruitment trends (young joining the adult population), the impact of conservation work to restore migratory pathways and a greater understanding of eel ecology in the Thames, such as the timing of migration and the distribution of elver (juvenile eels) through our rivers.

Photo of volunteers gathered round a sample tray on the riverbank

This information allows for evidence-based conservation management of the species. In another project, volunteers have helped gather data that has successfully made the case for increased investment into removing sources of pollution from rivers. The outfall safari project in 2016, 17 saw 112 trained volunteers join us to survey 142 km across London to record pollution problems at outfalls. This has led to a future commitment from Thames Water to triple the number of polluting outfalls than they currently clean.

There is a wonderful culture of volunteering in the UK and environmental citizen science is part of this. It follows a great linage of amateur ecological observers that goes back to Gilbert White and even Charles Darwin who, as an independently wealthy man, could be classified as a citizen scientist (albeit a rather influential one) but would Darwin have joined us in measuring eels, I hear you ask? As a man who asked his son to play the bassoon to earthworms in pursuit of his phenomenal drive to observe the natural world, I think he would have had no hesitation in donning his welly boots and joining us as an eel monitor.

Photo of Joe Pecorelli giving a presentation to volunteers

Anyway, I digress! We benefit from and celebrate this great culture of citizen science whilst at the same time sound a note of caution: We mustn’t see the willingness of volunteers to monitor our environment become an excuse for the withdrawal of central government funds for frequent and rigorous monitoring of our rivers by a well-resourced Environment Agency. Citizen science adds value but should not replace government responsibility.

If you are over 16 and would like to join us as a citizen scientist on the Thames and rivers throughout London you would be very welcome, please click below to sign up to our citizen science mailing list.

Volunteer as a Citizen Scientist

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