Distribution, status and movement patterns of Curlew Sandpipers Calidris ferruginea among the islands of the Indian Ocean

Between 122,700 and 193,500 (and possibly as many as 320,000) Curlew Sandpipers spend the non-breeding season on islands of the Indian Ocean, mostly on western and central islands. Five islands (Pemba, Sri Lanka, Madagascar, Zanzibar and Mafia) account for 93–94% of the total. The largest uncertainty is the size of the population in Madagascar. Most Curlew Sandpipers probably reach islands in the western Indian Ocean from the east coast of Africa, and possibly also from north-west India. The absence of Curlew Sandpipers in the eastern Indian Ocean suggests that there is no westward trans-oceanic movement from south-east Asia. Most northwards migration is likely to be via the coast of Africa, but some birds might return north via south-west India.