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Thirty-one species of wader have been counted on the Manukau Harbour and Firth of Thames in summer and winter censuses since the winter of 1960. Data are presented on total numbers of waders, the numbers of selected wader species and the numbers of observers involved in the counts. The numbers of many native waders have increased during the last 39 years, especially Pied Oystercatchers (Haematopus ostralegus), which have increased 8-fold from the 1960s to 1990s; however, Pied Stilts have been stable and Wrybills (Anarhynchus frontalis) may be declining. Numbers of many Arctic wader species have increased on one or both harbours, but of the two main species, Bar-tailed Godwits (Limosa lapponica) have remained constant over both harbours and Lesser Knots (Calidris canutus) have declined slightly on the Firth of Thames but increased greatly on the Manukau Harbour. Notable changes of habitat are noted and possible reasons for changes in abundance of some species are discussed. Likely seasonal maxima of wader numbers are considered and the implications of these are discussed.