2025/10/02 by Jaelen N. Myers, Marcus Sheaves, Kátya Abrantes +4 · 1 voice
Environmental Science · Agricultural and Biological Sciences · #Ichthyology and Marine Biology #Aquatic life and conservation #Fish Biology and Ecology Studies
paper · doi:10.3354/meps14989
openalex publication_date 2025/10/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/11
Intertidal zones support diverse assemblages of juvenile rays. However, limited knowledge of species’ diets, particularly during early life stages, translates to a poor understanding of which prey resources support their abundances or how species coexistence is facilitated through resource partitioning mechanisms. This study investigated the trophic ecology of 4 juvenile ray species at an intertidal sand flat in Queensland, Australia, using complementary approaches. Stomach contents were collected using gastric lavage (i.e. gut flushing) to describe the dietary composition of each species, while trophic niche size and overlap were quantified using stable isotope analysis (δ13C and δ15N). Furthermore, benthic prey availability was surveyed to contextualise dietary preferences and fine-scale foraging patterns. Cowtail stingrays Pastinachus ater had the broadest isotopic niche and fed mostly on polychaetes, bivalves, and gastropods. Australian whiprays Himantura australis primarily fed on decapod crustaceans and had a smaller trophic niche size than P. ater. Critically endangered giant shovelnose rays Glaucostegus typus and brown whiprays Maculabatis toshi both had narrow isotopic niches and specialised on penaeid prawns, suggesting direct competition during young-of-year life stages. Benthic invertebrates were abundant within the study area, although there was some patchiness across sites with different microhabitat features. This heterogeneity, combined with vertical distributions of prey throughout the sediment column, provided insights into how species-specific foraging strategies shape dietary variability. This study provides foundational knowledge on the diets of 4 understudied ray species during early life stages and how species’ morphologies and foraging strategies may facilitate the exploitation of different prey resources.