Abstract
Citizen science and informed citizens have become fundamental in providing the first records and accounts about the expansion of numerous non-indigenous species. However, implementing a successful citizen science campaign can be expensive and particularly difficult for aquatic species. Here, we demonstrate how a low-cost citizen science campaign and its outreach plan in social and traditional media enabled to track the expansion of the Atlantic blue crab Callinectes sapidus Rathbun, 1896 along the coast of Algarve (southern Portugal, Europe). We describe the outreach strategy and a cost-benefit analysis of the first year of the citizen science campaign. Social media platforms allowed us to reach a significant number of citizens (over 31,500 clicks in Facebook publications), while traditional media gave national visibility to the citizen science campaign and biological invasions. In only 1 year, we documented the spread of the invasive Atlantic blue crab across the entire 140 km of the Algarve coast with 166 valid observations referring to 1747 specimens, submitted by 62 citizen scientists. We spent 0 € on the citizen science campaign, but considering the time invested in the campaign the cost would have summed up to 3,751 €, while the total minimum cost for one scientist to go to the field and retrieve the equivalent information would have exceeded 11,000 €. We used free online tools of communication to obtain the records about the Atlantic blue crab, instead of a dedicated web platform or mobile app, and handled social media accounts ourselves, which saved us at least 18,815 €. The citizen science campaign revealed that the Atlantic blue crab is unequivocally established in southern Portugal and that females appear to exhibit summer migrations to coastal areas to spawn as in the native area. Overall, our low-cost citizen science campaign effectively documented the rapid spread of a marine invasive species while providing some insights into its ecology. Our strategy can be easily replicated and implemented elsewhere in the world to tackle the ever-growing problem of biological invasions while increasing the scientific literacy of local populations.
Highlights
Environmental agencies and scientists struggle to implement efficient monitoring and management programs focused on biological invasions given its pervasive nature (Pyšek and Richardson, 2010; Courchamp et al, 2017), despite the increased global awareness about biological invasions and their impacts on the environment, biodiversity, and economy (Simberloff and Rejmánek, 2011; Dehnen-Low-Cost Monitoring of Marine Invasive SpeciesSchmutz et al, 2018)
During NEMA’s first year, we focused mainly on social media outreach which resulted in traditional media becoming interested in the subject (Figure 2C)
Between April 2019 and March 2020, two interviews were broadcasted on national television, fifteen online articles were published, two articles published on printed newspapers with one making cover page, and two interviews given to radio stations. The content of these news pieces included the discovery of non-indigenous species (NIS) in Algarve and NEMA’s citizen science campaign
Summary
Environmental agencies and scientists struggle to implement efficient monitoring and management programs focused on biological invasions given its pervasive nature (Pyšek and Richardson, 2010; Courchamp et al, 2017), despite the increased global awareness about biological invasions and their impacts on the environment, biodiversity, and economy (Simberloff and Rejmánek, 2011; Dehnen-Low-Cost Monitoring of Marine Invasive SpeciesSchmutz et al, 2018). Aquatic invasive species are challenging to monitor and study due to the difficulty in accessing their habitats which increases costs while delaying the detection of new non-indigenous species (NIS) (Streftaris et al, 2005; Havel et al, 2015). With funding increasingly scarce towards long-term scientific projects and monitoring campaigns, scientists must consider every available tool to increase early detection rates, including citizen science (Gallo and Waitt, 2011; Azzurro et al, 2013; Morais et al, 2019; Encarnação et al, 2021; Pernat et al, 2021). Citizen scientists reported the first records of several marine NIS in the Mediterranean Sea (Azzurro et al, 2013, 2019; Zenetos et al, 2013), while fishers reported two new marine NIS in southern Portugal (Morais and Teodósio, 2016; Morais et al, 2019)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
