Erin Roger, Cameron Slayter, Dax Joseph Kellie, Peter Brenton, Elycia Wallis, Olivia Torresan, Andre Zerger

Citizen science continues to make a substantial contribution to a wide variety of scientific disciplines by allowing the public to be involved in activities like idea generation, study design, data collection and analysis. Although the pace of citizen science has exploded in recent decades, there remains untapped potential for scientific output through investment in research infrastructure that more specifically supports citizen science activities. Here, we provide a case study of how the biodiversity data aggregator the Atlas of Living Australia (ALA) has supported the growth of citizen science over the past decade. We show that around one quarter of data collection projects provide around half of all species observation records in the ALA, supplementing specimen-based data to provide more comprehensive visualisation of species distributions. We then discuss how large data aggregators like the ALA support common challenges of the citizen science community by implementing tools to standardise complex data, safely store sensitive data, and improve participation and discoverability of citizen science data. Our findings demonstrate the importance of investment in research infrastructure to support and augment the scientific value of the citizen science movement globally.