Turtle Doves, trial plots and Trichomonas: understanding and conserving the UK's rarest dove

The Turtle Dove Streptopelia turtur is the UK’s only migratory dove. Wintering in sub-Saharan Africa and breeding across Europe and Asia, from Portugal in the west to Mongolia and western China in the east, its population has declined rapidly in recent years. In the UK, at the northwestern edge of the species’ range, populations have declined by a sobering 98% since 1970 (Hayhow et al. 2017). At the edges of the range of any declining species, you often expect to see faster declines than in the centre of the range. Yet, worryingly, the picture for Turtle Doves across Europe is also bleak: the Pan-European Common Bird Monitoring Scheme shows a population decline of 80% since 1980 (PECBMS 2019). In 2015, the species was classified as Vulnerable by the IUCN (Birdlife International 2017). The research described in this article, carried out by the RSPB and funded jointly by the RSPB and Natural England through the Action for Birds in England partnership, began in 2010 when the UK Turtle Dove population had fallen by 89% since 1970 (Eaton et al. 2010). When trying to understand why bird populations are declining it can be difficult to know where to start, especially when you have a migrant species that may be facing problems on its breeding grounds, wintering grounds, or on migration