Comparative multi-habitat assessment of foraging success in two globally threatened shorebird species during the non-breeding season along the west coast of India

This study investigated the foraging success of wintering Eurasian Curlew (Numenius arquata) and Bar-tailed Godwit (Limosa lapponica) in different intertidal habitats along the west coast of India, including mudflats, mangroves, and sand beaches. Behavioural data collected from January 2010 to December 2021 were used to assess prey capture success rates and feeding abundance across these habitats. Significantly higher prey capture success rates were observed in mangroves, compared to mudflats and sand beaches. Eurasian Curlew exhibited higher prey capture success on sand beaches, whereas Bar-tailed Godwit foraged more efficiently in mangroves. These patterns are likely driven by species-specific factors, particularly differences in morphology and foraging strategies. Sediment texture changes and alterations in prey behaviour were identified as primary drivers of the observed patterns. The declining prey capture success rates over the years suggest severe habitat degradation and reduced prey availability. Notably, prey capture success rates increased during the pandemic, highlighting human disturbances' impact. The findings underscore the need for further research to unravel the diet spectrum as an indicator of habitat quality.