Behavioural synchronisation of wintering Tundra Swans (Cygnus columbianus) varies with spatial position, time of year and habitat
By Zhiru Lu, Shilong Yu, Aping Zhu, Guy Beauchamp & Chunlin Li
For group-living animals, behavioural synchronisation might represent a strategy to increase survival in varying environments. However, synchronisation patterns and the driving factors remain largely unknown, particularly for species living in harsh conditions, such as waterbirds in winter.
Tundra Swan Cygnus columbianus by Nick Cottrell
From October 2023 to March 2024, we recorded videos of foraging flocks of Tundra Swans (Cygnus columbianus) in grassland, mudflat, and shallow water habitats at Shengjin Lake, China, and quantified behavioural synchronisation through two metrics: time synchronisation rate (TSR, the proportion of time spent in synchronised states) and behavioural transition synchronisation rate (BTSR, the proportion of synchronised behavioural transitions). Generalised linear mixed models were used to assess the effects of spatial position within flocks, time of year, and habitat. Within flocks, swans that were close to one another showed significantly higher TSR and BTSR than those further apart. TSR but not BTSR significantly decreased over winter. Habitat type influenced BTSR, with less synchronisation in shallow water habitats than in grasslands and mudflats. In addition, the negative impact of inter-individual distances was more pronounced in the shallow water habitat.
The findings support the idea that synchronisation is the result of copying the behaviour of close neighbours. Furthermore, environmental factors like time of year and habitat type can also modulate synchronisation. These findings enhance our understanding of the adaptive role of behavioural synchronisation in Tundra Swans inhabiting dynamic wetland habitats.
The full article can be found here
