This article presents a comprehensive global review of marine citizen science projects and their contribution to marine conservation, conducted in the context of urgent needs to address climate change, overfishing, marine pollution, and other anthropogenic threats to global oceans. The study was particularly timely given the United Nations Decade of Ocean Science for Sustainable Development 2021-2030, which aims to build capacities for governments and communities to enable conservation action worldwide.
The researchers employed an online global survey methodology to collect data from marine citizen science project managers, leaders, and organizers worldwide. The survey was designed to assess project adherence to the Ten Principles of Citizen Science, which were established by the European Citizen Science Association in 2018 to provide a foundation for good practice in citizen science. These principles cover aspects such as citizen involvement in scientific endeavors, genuine science outcomes, benefits to both science and society, data sharing, quality control, and ethical considerations.
The study documented 74 marine citizen science projects distributed across 51 peer-reviewed journals from environmental education, education, conservation, and natural sciences fields. The geographical distribution was primarily clustered in Europe, North America, and Australia, with some projects in South Africa, Latin America, and New Zealand. The total number of active participants within projects ranged from approximately 5 to 7,000 participants, with a mean of 720 and median of 200 participants.
Projects were categorized into three size groups for analysis: Group 1 (35 projects with 0-99 participants), Group 2 (24 projects with 100-999 participants), and Group 3 (15 projects with ≥1000 participants). Significant differences emerged between size groups in their methods of engaging citizen scientists, types of training provided, and funding sources. Larger projects were more likely to have established websites, developed mobile apps, and used online platforms for participant education.
The projects focused primarily on coastal habitats including rocky seashores, beaches, and open ocean areas, which aligns with other research documenting marine citizen science in easily accessible coastal environments. Overall, 85.5% of projects engaged in biodiversity monitoring activities, with 65.2% focusing on species identification and 56.5% on quantifying marine species. Projects addressed diverse topics including habitat protection and restoration, endemic wildlife, water quality, energy conservation, climate change, and marine pollution.
In terms of partnerships and funding, 80.3% of marine citizen science projects had developed partnerships with multiple organizations across sectors, predominantly with civic organizations (62%), science institutions (76.1%), and government agencies (69%). The majority of projects (86.3%) received funding from multiple sources, including government (54.8%), universities and research institutes (30.1%), environmental agencies (16.4%), NGOs (20.5%), and private enterprises (31.5%).
The assessment against the Ten Principles revealed mixed adherence across projects. Most projects followed principles related to data sharing, acknowledging citizen contributions, and considering legal and ethical issues. However, significant gaps emerged in citizen involvement throughout the scientific process, with most projects being contributory rather than collaborative or co-created. Participants were primarily involved in data collection, with limited engagement in research design, analysis, or publication phases.
Principle #1 (citizen involvement in scientific endeavor) showed that while citizen scientists contributed to data collection, they had minimal involvement in project design, analysis, or output phases. Only a few projects were truly co-created, such as Friends of Gulf of St Vincent in Australia and Community Marine Biodiversity Monitoring in Scotland.
Principle #2 (genuine science outcome) was met by 73% of projects, though publication rates were generally low. Medium-sized projects were more likely to produce scientific articles, while smaller projects were less likely to generate data for scientific use.
The study highlighted several exemplary projects demonstrating different approaches to marine citizen science. Redmap Australia uses an opportunistic approach where recreational fishers and divers submit photographs of species observed outside their known distributions, contributing to climate change research. Snapshot Cal Coast employs a bioblitz approach using iNaturalist to document Californian coastal ecology. Reef Life Survey engages highly trained citizen science divers to conduct structured underwater surveys, resulting in significant scientific output with over 77 scientific papers and management reports.
The researchers identified several limitations and future directions. The survey was predominantly representative of Western regions, potentially reflecting bias in survey promotion methods. They emphasized the need to create and extend networks of marine citizen science projects globally, particularly in underrepresented regions including Asia and Africa. The study also highlighted the need for more detailed evaluation of participant experiences and the development of frameworks to better assess conservation outcomes.
The findings suggest that marine citizen science has significant potential to contribute to the UN Ocean Decade objectives by generating scientific data, increasing public engagement, and supporting marine conservation efforts. However, realizing this potential requires addressing current limitations in participant involvement, scientific output, and global representation. The researchers recommend developing evaluation guidelines, improving participant engagement across the entire scientific process, and creating platforms for international knowledge sharing and collaboration.
The Bottom Line
This global review by Kelly et al. (2020) examined 74 marine citizen science projects worldwide to assess their extent, potential, and contribution to marine conservation. The study evaluated projects against the Ten Principles of Citizen Science defined by the European Citizen Science Association to determine best practices and identify opportunities for improvement. The researchers found that marine citizen science projects are predominantly clustered in Europe, North America, and Australia, with most focusing on coastal habitats and biodiversity monitoring through data collection activities. While the majority of projects followed the Ten Principles in practice, adherence varied significantly - most were contributory rather than collaborative, with participants primarily involved in data collection rather than other stages of the scientific process. The findings demonstrate that marine citizen science presents a promising avenue to enhance engagement in marine conservation globally, particularly as highlighted by the UN Decade of Ocean Science for Sustainable Development 2021-2030. However, greater emphasis is needed on involving participants throughout the entire scientific process, improving scientific publication rates, and developing more comprehensive evaluation frameworks to maximize conservation impact.