Most of the waders (also called shorebirds) inhabit shorelines or mudflats. Technically, the waders are defined by taxonomy rather than by habitat. The waders are the species in the suborder Charadrii. There are 10 bird families in this suborder. The most prominent are the sandpipers, snipes, curlews, plovers, lapwings, oystercatchers, turnstones, stilts and avocets, and most of these commonly feed by “wading” in shallow water, so the label “wader” fits well. The thick-knees, jacanas, coursers and pratincoles are also in the suborder but are less obviously “waders” because they don’t wade in water. But they are closely related, and are placed in the wader “family”.
The suborder Charadrii contains about 210 species worldwide. Many of these waders are long-distance migrants; some are residents. For example, the Curlew Sandpiper andthe Ruddy Turnstone breed on the tundra in northern Siberia, and migrate mostly to Africa, south of the Sahara Desert, and to Australasia, for the non-breeding season. At the other end of the migrant-resident spectrum is the African Oystercatcher – pairs spend decades on their territories, which can be a few hundred metres in length.
Below are two photographs of the Sanderling Calidris alba, a classic long-distance migrant, one on the breeding grounds, and one on the non-breeding grounds.
Most of the species in the Family Glareolidae (coursers and pratincoles) in southern Africa are nomadic. Examples are Double-banded Courser and Burchell’s Courser. The Black-winged Pratincole is a long-distance migrant from Eurasia in the southern summer; while it is in southern Africa for the non-breeding season, it is nomadic.
The International Wader Study Group (IWSG) is the society which brings together everyone who has a passion for waders, their habitats and their conservation. Members include research scientists, citizen scientists and conservation practitioners from all countries. The IWSG produces the journal Wader Study which publishes papers about the science of waders from all over the world.