Unique foraging behaviours among sympatric stingrays in a reef-flat nursery

Context Intertidal reef flats serve as communal nurseries for juvenile rays, where they perform important functional roles. Although detailed assessments of foraging behaviours would provide critical insights into resource use and fine-scale trophic interactions among species, this has largely been unexplored. Aims We compared the foraging behaviours of cowtail stingrays (Pastinachus ater), mangrove whiprays (Urogymnus granulatus) and pink whiprays (Pateobatis fai) at Pioneer Bay, Orpheus Island, to assess temporal foraging patterns and to compare species-specific resource use and functional roles. Methods In 2021 and 2023, individual rays (n = 96) were followed within the intertidal reef flat for 7–18 min (mean = 13.5 min) by using aerial drones at heights of 3–5 m, and details were recorded on all foraging behaviours. Key results P. ater and U. granulatus fed more frequently during low tidal heights, which decreased with rising tidal levels. Both P. ater and P. fai preferred foraging on smooth sand substrates and primarily used non-disruptive feeding behaviours. Species-specific foraging patterns were also observed, such that P. ater showed greater preferences for intense excavation and U. granulatus preferred feeding among coral rubble more than did other species. Conclusions These species exhibited distinct foraging strategies that may enable resource partitioning, although overlap in other aspects of foraging and space use may also assist in maintaining functional redundancy within the reef flat nursery. Implications Behavioural data provide meaningful insights on foraging mechanisms, particularly if results are interpreted alongside other methods in future research.