Detailed data on shorebird feeding ecology is mostly lacking for tropical wintering sites, limiting our understanding of trophic interactions among shorebird species and their prey. Using dropping analysis and video recordings we compared the diet of eight shorebird species wintering in the Bijagós archipelago, Guinea-Bissau, one of the most important but also least known coastal sites for shorebirds in Africa. We also calculated niche width and foraging niche overlap among these eight species.

Whimbrel, grey plover and redshank fed mainly on fiddler crabs, confirming previous observations made in the Bijagós. A large proportion of the diet of bar-tailed godwit, curlew sandpiper, sanderling and ringed plover was composed of polychaetes, particularly Nereis and Glycera, and also Marphysa in the case of larger shorebirds. Red knots fed mainly on the bivalve Dosinia isocardia. All species showed narrow trophic niches, but particularly so whimbrel, red knot, grey plover and redshank. Niche overlap among shorebird species was mostly insignificant, with the exception of species that fed mainly on fiddler crab.

Low levels of niche overlap suggest that shorebirds are able to partition the available food resources in the Bijagós despite the reported low macrobenthic densities in the area. In fact, observational data for bar-tailed godwit suggests resource partitioning even occurs within species, with dietary differences among sexes.