This Scientific Study took place from 29 October to 8 November 2002 at Pennefather River and from 14 to 26 November at Sweers Island. The report of the study has been published. Click here for the order form.
Lying entirely within the tropics, the climate is characterised by constantly high temperatures, 12 hours of daylight almost year round and a heavy, markedly seasonal annual rainfall under the influence of the monsoon. Rainfall decreases with increasing latitude and the pattern of alternating flood and drought is a dominant feature of the climate. High levels of cyclonic activity are both destructive (loss of seagrass and mangroves) and constructive with run-off from heavy rains mobilising large quantities of sediment into southern Gulf coastal habitats and recharging aquifers. One of the four major drainage systems in northern Australia, the Gulf is a shallow, large embayment formed when the brackish Lake Carpentaria was flooded between 10 000 and 6 000 years ago.
As 2002 was the bicentenary of Matthew Flinders' circumnavigation of Australia, the Society chose as its 2002 scientific study two Gulf sites, Pennefather River and Sweers Island. These were major collecting areas during Flinders' voyage in 1802.
Pennefather River, 12º14"S 141º46"E, is situated approximately 45 km, and about 1¼ hrs by road, from Weipa. It is located in an area of exposed coastline with Holocene and Pleistocene sand barriers separated by a plain comprising salt flats and saltmarshes dissected by mangrove-fringed tidal creeks. The study focussed on the northern bank of the river which has had little human modification.
Sweers Island, 17º06"S 139º37"E, is the most south-easterly of the Wellesley Group, approximately 138 km from Karumba. It became an island about 7 000 years ago and the landscape records the effects of changing sea level since that time, particularly the overlay of limestone. It is a relatively flat island with areas of swamp and a number of vegetation communities including Allocasuarina, Acacia, Melaleuca and Eucalyptus.
Sweers Island is one of several traditionally owned by the Kaiadilt people who, in the main, live on Mornington Island. An Aboriginal term for the island describes it as "men absent islands". Anthropologists including Tindale suggest that prehistoric use of Sweers was sporadic and ecologically insignificant. Today, some of the Kaiadilt people are returning to live on Bentinck Island and travel regularly to Sweers. Bentinck Island lies only 4 km away across Investigator Roads so researchers were able to access study sites there. Scientists also travelled to Bountiful and Pisonia Islands.
Liaison with Traditional Owners
Comments from Matthew Flinders' journal
On Sweers Island and surrounding waters:
Much of the above information on the Gulf of Carpentaria was adapted from: Sinclair Knight Merz, October 1997, Wellesley Islands & Region Marine Field Survey Interim Report.