| Summary: | This is the third report in a series documenting the location and status of selected faunal assemblages on the Northern Territory coastline, offshore islands and Top End wetlands. Previous reports in the series considered waterbird and seabird breeding colonies. This report briefly summarises the status and distribution of selected migratory and resident shorebirds in this large area. More detailed papers on species and areas will be written at a later date. Prior to 1990 little information existed on the distribution and abundance of shorebirds around the Northern Territory coast and adjacent wetlands. Information gathered during my aerial and ground surveys between 1990 and 2001 has now clearly shown that the coast and coastal wetlands of the Northern Territory have globally significant numbers of many species of shorebirds. Over the 12 year period I made nearly 13 000 separate records of shorebirds in the survey area. These records totalled around 2.1 million birds. Shorebirds were recorded on all parts of the Northern Territory coast, nearly all islands and most of the wetlands. Shorebirds were most numerous in Anson and Fog Bays on the west coast; the south shore of Van Diemen Gulf east of Darwin; Boucaut, Castlereagh and Buckingham Bays and the Cadell Straits on the north coast; and the area between the Roper and the Limmen Bight Rivers and the Port McArthur areas on the east coast. Each of these areas, and more, would qualify for nomination to the East Asian-Australasian Shorebird Site Network and/or as Ramsar sites. Especially important in many of these areas were the very high numbers of migratory shorebirds that were present during the Northern Hemisphere breeding season (June to August). These birds are likely to include many immature birds and may include some that are partaking in partial migrations from southern Australia but not going any further. Areas that my surveys indicated as having relatively few shorebirds included most of the north coast of the Tiwi Islands and Cobourg Peninsula (including the coast to its east), the north west coast of the Gulf of Carpentaria and most of the offshore islands, including Groote Eylandt. Many of the species discussed in this report were found throughout the survey area and were found in greater numbers than previously suspected. Easily the most abundant species was the Great Knot. This species is likely to have a peak population in excess of 120 000 birds around the Top End coast. Larger, short-term populations of Little Curlew are likely to occur, but these were not recorded in these surveys. The next most abundant species were the Bar-tailed Godwit, Black-tailed Godwit, Greater Sand Plover, Lesser Sand Plover and Red-necked Stint. There are also many other species for which the Top End appears to have a significant proportion of the Australian population. Of the 33 species discussed in this report, as many as 26 species are likely to be present in at least one site along the Northern Territory coast and Top End wetlands in numbers greater than 1% of the estimated minimum flyway population. Species for which the Top End has only a small proportion of the Australian population, include Snipe spp., Wood Sandpiper, Sanderling, Sharp-tailed Sandpiper and Curlew Sandpiper. Most of the species discussed in this report are non-breeding migrants, however there are some that breed in the survey area. Little emphasis was given to searching for single breeding pairs in these surveys and no examples of colonial or even loose aggregations of multiple breeding birds were located. Some resident species (eg Beach Thick-knee and both Oystercatchers) bred in scattered pairs throughout the survey area. Others (eg Red-capped Plover) do breed in the survey area but most of the breeding population probably moves inland and/or south of the study area to nest. Shorebirds, like most of the other fauna of the Top End of the Northern Territory, are in a very unique position. Not only is there an immense amount of habitat which supports large populations of many species, but most of the area is very remote and has not been subject to many of the pressures associated with large human populations. Although this is likely to remain the case for the short term at least, it is equally likely that the pressures of human expansion within Australia, especially in coastal areas, will see some of this area targeted for development at some stage in the more distant future. It is for this eventuality that we must be prepared. We must therefore ensure the security of the more significant of these areas before problems arise. Locating coastal fauna sites and documenting them in this series of reports is the first step in that process. EXECUTIVE SUMMARY -- LIST OF FIGURES -- LIST OF TABLES LIST OF PLATES -- ACKNOWLEDGMENTS -- BACKGROUND AND OBJECTIVES -- STUDY AREA AND ENVIRONMENT -- SPECIES SELECTED -- METHODS -- SHOREBIRDS – BY SURVEY BLOCK. -- SHOREBIRDS – BY SPECIES. GROUP 1 SPECIES -- SHOREBIRDS – BY SPECIES. GROUP 2 SPECIES -- SHOREBIRDS – BY SPECIES. LESS COMMON SPECIES -- ESTIMATION OF TOP END SPECIES PEAK NUMBERS -- FUTURE RESEARCH -- REFERENCES -- PERSONAL COMMUNICATIONS -- APPENDICES. Date:2003 Cover title.
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