Grégoire Michel, Josh Nightingale , Martin Beal, Alice Bernard, Maria P. Dias, José A. Alves

Electronic tracking has enabled rapid advances in knowledge of the movement behaviour and habitat use of shorebirds (Charadriiformes), and is thus making a growing contribution to their conservation. However, developing a useful coherent global strategy for tracking these taxa requires an overview of the current availability of data and how it varies along regional and ecological lines. To this end we undertook a comprehensive review of published shorebird tracking studies. We reviewed 353 scientific publications covering 73 species from five shorebird families. Over half of species, and half of families, lacked any tracking publication. Migratory species were more likely to be tracked, as were those of intermediate body size. Data availability was considerably higher in temperate regions and in migratory routes that include wealthy countries, and very few tags were deployed in the Global South. In total, only 27.2% of publications reported that the data is archived in a repository, though this figure is increasing. We highlight species and regions whose conservation needs and lack of available data make them relevant priorities for future tracking research. Given the increasing impact and potential of re-using tracking data stored in online repositories to inform conservation, we emphasise the need to improve both the co-ordination amongst shorebird trackers to deploy tags strategically, as well as the urgency of archiving tracking data and making it widely available to researchers and conservationists.