Diamantina Floodplain


Site description (2008 baseline):

Site location and context
This IBA consists of floodplain, swamps and anastomosing channels of the Diamantina River and its major tributary Farrars Creek, to the east of Durrie Station in the Channel Country of central Queensland. The boundary is based on Wetlands International data and is designed to capture at least eight waterbird breeding colonies, including the largest in the Diamantina system (R. Jaensch in litt. 2008), e.g. an estimate of at least 46,000 and possibly many more waterbird nests at Kingadurka Waterhole in April 2000 (Costelloe et al. 2004). Much of the area is floodplain marshes and shrub swamps, especially lignum, interdune (swale) swamps and lakes between sand-dune country, and off-river swamps and lakes, notably Moonda and Shallow Lakes, large areas of which are dominated by swamp canegrass. The wetlands are mostly temporary, with inundation lasting from a few weeks to 6-9 months, but the site also includes numerous riverine waterholes, some of which may be semi-permanent (only dry in extreme drought). The IBA also includes the clay-pans to the south, which flood less frequently from local rainfall and support large numbers of birds for extended periods. The floodplain upstream and downstream is mostly too fast flowing to support significant numbers of waterbirds. The floodplain to the north and west holds water less frequently and is less well known, but may prove to meet IBA criteria. Similarly, with better survey data, the IBA could be expanded to include floodplain from the Monkira road crossing downstream to Stoney Crossing (half way between Birdsville and Durrie), including all the wetlands between dunes at the floodout of Farrars Creek, and some of the lower Farrars Creek. Wetlands west of Durrie homestead are briefly described in the Directory of Important Wetlands but the exceptionally valuable wetlands of the sand-dune swales around the junction of Farrars Creek and the Diamantina River remain poorly known. The climate is arid, with a mean annual rainfall of 169 mm recorded at Birdsville, 110 km to the west.

Key biodiversity
In April 2000 the IBA was estimated to support at least 450,000 birds (150,000 on floodplain and 300,000 in the swale swamps; Costelloe et al. 2004; page 485). At least seven waterbird colonies occur in swamps and around associated waterholes, west and east of Durrie homestead and in the northern parts of the swale swamp system in the east of the IBA - many of these are relatively small, supporting only a few hundred pairs of egrets, ibises, spoonbills, cormorants and pelicans (R. Jaensch in litt. 2008). The largest colony is around the eastern end of Kingadurka Waterhole and particularly in lignum-belalie shrub swamp extending south-east for several kilometres along a dune swale. ARIDFLO estimated over 46,000 pairs of all colonial species that normally breed in the region, except pelicans and terns. The colony is well known to long-term pastoralists in this area and is thought to operate on most major Diamantina floods. It is the largest known, mixed-species colony in the Lake Eyre Basin and was estimated in 2000 to support globally important numbers of Nankeen Night-Heron and Royal Spoonbill, and nationally important numbers of Glossy Ibis (estimated minimum of 8500 nests), Straw-necked Ibis (estimated minimum of 4500 nests) and Great Egret (estimated minimum of at Kingadurka Waterhole in April 2000). Breeding numbers of Great Egret are among the largest documented in Australia (Costelloe et al. 2004, page 492; R. Jaensch, Wetlands International unpubl. data). Lakes Moonda and Shallow probably support high numbers of Red-necked Avocet, Black-winged Stilt and migratory shorebirds (R. Jaensch in litt. 2008). A total count of 8194 waterbirds, including 1237 Australian Pratincole, was made during a flood in 2004 (Jaensch 2004). The IBA also supports a population of Yellow Chat and is a breeding location for the Freckled Duck (Jaensch 2003a). There have been three breeding records of the Australian Painted Snipe (listed as vulnerable under the EPBC Act) on floodplain and on off-river wetlands, and the species is probably a regular visitor (Jaensch 2003b; R. Jaensch in litt. 2008).

Pressure/threats to key biodiversity
Further surveys are required to assess specific areas of key importance and threats at these areas.

Land ownership
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Site access / Land-owner requests
Land-owner permission must be sought if leaving public roads.

Acknowledgements
Roger Jaensch of Wetlands International provided review comments and interpretation on the habitat and waterbird information.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Diamantina Floodplain (Australia). Downloaded from https://datazone.birdlife.org/site/factsheet/diamantina-floodplain-iba-australia on 23/12/2024.