De Grachtwacht
Coots, water lilies, Grebes, Dragonflies, plastic bottles, Rudds, Damselflies, biscuit packaging, and Seagulls. These are some of the silhouettes that might break the water surface on the canals of Leiden. However, only some of these things should be floating there. Liselotte Rambonnet and Auke-Florian Hiemstra, together with 500 volunteers, are trying to tackle this.
De Grachtwacht (The ‘Canal Watch’) is a Citizen Science project that is working to eliminate plastic from canals and inform people about the urban environment along Leiden waters. The Plastic Spotter canoe fleet sails every week for canal litter clean-ups. Based on the waste collected, sorted, and categorized, they investigate the sources of plastic pollution and aim to tackle the problem at its roots.
The most relevant discoveries are sometimes included in the Grachtwacht exhibition, in the bridge keeper's house on the Marebrug in Leiden. Here can be found different collections of urban nature. One of them is the showcasing of animals preserved in formalin that found its death by being entangled in plastics can be found here. Often, these animals are provided by animal ambulances and the animal rescue center of the city. These findings of great visual impact help to create engagement in visitors. Other collections show the most relevant litter findings found during clean-ups.
Through the years, many objects passed through this collection, from toys, and diaries, to 100-year-old dumps of hospital waste, with surgical scissors, x-ray sheets, and uranium glass.
The project got international media attention, with publications on CNN, The Guardian, the New York Times, and National Geographic. The work of the researchers Liselotte Rambonnet, Ph.D. candidate at the Institute of Biology Leiden, and Auke-Florian Hiemstra, Ph.D. candidate at the Naturalis in Leiden, together with 500 volunteers is giving concrete results in the city of Leiden, which is little by little reducing the quantity of plastic waste in the canals. Involving citizens allowed the general public to be more aware of the nature in their city. “The use of citizen science helps to make the public part of the solution”, says Liselotte, as well as that volunteers concretely contribute with their skills in identifying the litter or use their network and social media to enforce changes.
De Grachtwacht doesn’t only focus on clean-ups, but also scientific research is the engine of the project. Scientists and citizen side by side collect and study the litter collected during the clean-ups. For example, restaurants and cafés are among the main sources of plastic litter. Often it is possible to refer to the directly interested parties since restaurant menus can be traced back to the source. With this, can also be investigated how currents move plastics, and where it accumulates. When tracing back the source is not possible, they contact other relevant stakeholders like politicians, enforcers, or the water board.
Another research done by the project is mapping the canals’ biodiversity. Learning more about the species living in and around the watercourses helps them to understand the canal as an ecosystem and how to protect it.
When it is not possible to identify an organism, they collaborate with Jordy van der Beek who analyses the DNA, to learn more about the species living in the canals. Also, radiological imaging produced by Thomas Ruytenberg is used to study dead animals from human litter and how their anatomy can suffer from human waste. (Many of the other volunteers making tangible contributions to the initiative can be found on the Grachtwacht website.
It all started with the “Canal Cups” campaign of 2019, which dealt with the problem of single-use plastic landing in the canals after big events like Leidens Ontzet and King's Day. By individually photographing on Instagram, more than 8000 cups that were found after King's Day, they were able to convince the municipality of Leiden to unilaterally require the provision of reusable deposit cups at all public events in Leiden. With this excellent example, many other cities followed suit with the same policy. But the volunteers who helped take the photos, and those who attended the campaign’s photo exhibition, continued to ask ‘What else is floating in the canals?’. After this successful campaign, during the 444th anniversary of Leiden University through a call for questions from the public by the CS Lab, this question came to the top again… The De Grachtwacht project was initiated.
For early career researchers in Citizen Science, Liselotte suggests involving the citizens as much as possible in the project, making sure to consider people’s backgrounds, motivations, and expectations and how to use those in the best way. Also, the time spent coordinating, communicating, and recruiting volunteers shouldn’t be underestimated. Lastly, connecting or adopting already existing citizen science projects might often be the best option.