The importance of raising citizens’ awareness
Quite surprisingly, urban environments host an important proportion of the overall biodiversity, but urban areas, as highly altered systems, can also act as a “source” of opportunistic invasive alien species (IAS) for other environments, since citizens are the ultimate recipients of non-native plants and animals, including wildlife, from the international trade(e.g. gardening and pet trade).
It is clear that the urban environment can play a much wider and important role in addressing the risks of biological invasions. This can be achieved by making citizens aware of the importance of biodiversity and promoting management actions by the competent administrations.
Human perceptions of nature and the environment are increasingly being recognized as important for environmental management and conservation. In fact, the management of IAS, particularly those introduced as pets, is often opposed by a large part of the public, and it is therefore crucial to explain the reasons behind any control program, to mitigate the conflicts that may raise. Such is the case of Gray squirrel in Italy, where the start of the eradication campaign was delayed by the strong opposition of some local associations and groups of citizens. They were not convinced by any evidence of the risk the American squirrels pose to the native red squirrels (bit.ly/3U5GHaf).
It is probable that most of the animal IAS raise this kind of public empathy, while many plant species are considered a real nuisance. For example, the Japanese knotweed is almost universally disliked. In Swansea (UK), awareness raising initiatives have enabled the public to become fully aware of the plant and impact, endorsing its management. Citizens are very active in identifying new infested sites and reporting movement of the plant, highlighting where treatment is not carried out properly (bit.ly/3U5GHaf).
IAS invasions in urban areas are problematic because of negative impacts on ecosystem services upon which human societies depend. They can also create diverse ecosystem disservices, for example by acting as vectors of human and animal diseases, causing toxicity and allergic reactions, or by exacerbating problems like fire at the urban–wildland interface.
It is therefore important to involve citizens in the identification and reporting of IAS. Towards this end, Bioblitz is one of the most used events. Its objective is to find and identify as many plants, animals, and fungi as possible in a specific area usually over 24 hours.
The City Nature Challenge (CNC) started in 2016 as a competition between Los Angeles and San Francisco, and has grown to an international event, motivating people around the world to find, document and share observations of nature wildlife in their cities.
In addition, dedicated platforms, such as iNaturalist, allow volunteers to contribute seamlessly reporting species observations. Some initiatives, address specific objectives with the help of citizens. Such is Flatworm watch aimed at elucidating which species of non-native terrestrial flatworms are present in gardens and nature in Belgium.
Citizens and other urban stakeholders play a vital role, and their contribution can support the strengthening of collaboration with local and regional authorities in support to IAS management, and biodiversity and ecosystems conservation, improving quality of life in cities and achieving national and international biodiversity targets.
To find out more:
Non-native species in urban environments: patterns, processes, impacts and challenges
Explaining people's perceptions of invasive alien species: A conceptual framework
Perceptions of impact: Invasive alien plants in the urban environment