News Release

One of the largest citizen science activities for marine biodiversity in Spain announces its results

The third edition of the BioMarathon saw more than 60,000 citizen science observations of marine life along the Catalan coast

Reports and Proceedings

Pensoft Publishers

BioMarathon Diving Activities


Citizen Scientist diver photographed underwater during the BioMarathon.

view more 

Credit: Xavier Salvador, MINKA

The primary objective of the ANERIS project (Horizon Europe GA: 101094924) is to address the alarming decline in ocean biodiversity through creation of cutting-edge technology designed for the monitoring and research of marine life. A significant focus of ANERIS is the close involvement of local communities with the scientific process through  the organisation of large-scale citizen science activities. The summer of 2023 saw the exciting start of one of the largest such activities in Spain:

The third edition of the BioMARathon,  co-funded by the ANERIS, MINKE, ECS, and GUARDEN Horizon projects, and organized by EMIMBOS (ICM-CSIC), MINKA, Anèl·lides, FECDAS, Plancton diving, Centre d’Estudis del Mar ( Barcelona Provincial Council), represents a large collaborative effort to promote citizen science, empower locals, gather extensive marine biodiversity data, improve the MINKA citizen science platform, and increase community engagement in the research and protection of marine biodiversity and habitats.

The third year of the BioMARathon was also the most successful by far, with over 300 volunteers between the 1st of May and the 15th of October, collecting more than 60,000 observations of marine life along the Catalan coast (triple the number from 2022), including 34 invasive and 40 protected species, as well as the previously-unrecorded presence of the African fiddler crab (see image). 

All observations, each including an image with corresponding geolocation are collected using the MINKA app, and feed into a dedicated database. Over the last three years, BioMARathon observations have catalogued a total of 1900 marine species along the Catalan coast, creating one of Catalonia’s most extensive marine biodiversity databases thanks to the dedication of the public. In 2023 alone, 1440 species were recorded with the notable identification of the African fiddler crab (Afruca tangeri) which continues to infiltrate into habitats deeper in the Mediterranean basin.

Notable invasive species include green and red algae (C. cylindracea & A. taxiformis), while the protected ones include various rays (e.g R. undulata & M. mobular), as well as red coral (C. rubrum) and several protected seagrasses playing a crucial role in ecosystem formation, erosion prevention and storage of carbon dioxide.

The BioMARathon activities featured a friendly competition between the provinces of Girona, Barcelona and Tarragona for the number of recorded observations. All three provinces were supported by diving clubs facilitating various snorkeling and diving activities. In Barcelona, collected observations will be used to update the information of the interactive Barcelona City Biodiversity Atlas, creating a new dedicated layer for molluscs and crustaceans.

An extensive breakdown of the BioMARathon results was presented in an online event on November 30th (2023), and an in-person celebration with some of the organizers and citizen scientist participants was carried out on the 15th of December. On behalf of the entire ANERIS team, we would like to extend our gratitude to all the organizers, participants and everyone involved in the 2023 BioMARathon and we look forward to an even more successful edition in 2024.

Read more here.


ANERIS receives funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No 101094924. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the EU nor the EC can be held responsible for them.


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.