Researchers still don’t know what caused massive and mysterious mangrove dieback in the Gulf of Carpentaria though the problem appears to have eased in the wet season.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
James Cook University researcher Professor Norm Duke said the dieback occurred in dry hot conditions which have now eased.
“The question is will such adverse conditions return in another dry period? “ Dr Duke said.
Dr Duke said he was concerned there were no further measurements, records or surveys describing more of the severe dieback in the Gulf region.
“There is always going to be patchy dieback from a variety of local, smaller-scale causes,” he said.
“Then there is the on-going condition of known amd measured dieback impacted sites across an unprecedented area which while not getting larger, these existing areas are deteriorating progressively.”
Dr Duke said this was to be expected in places after forests of trees have died.
“My initial evidence has been the mobilisation of fine sediments as the smaller feeder roots rot away - no longer binding shallow surface sediments,” he said.
“As the years pass, this initial wash of sediments will grow exponentially leading to the sometimes dramatic erosion of coastline with the re-displacement of sediments across the region.”
Dr Duke also warned of the real risk also of tropical cyclone wind and wave action during the next decade and more.
“The expected erosion will have notable impacts on surrounding habitats – leading to likely further dieback patches,” he said.
“The likely consequences -as yet unquantified - include the livelihoods of those who depend on the local fishing industry.
“With such a loss to mangroves, we expect there are impacts on all forms of fisheries – as well as the changes to shoreline stability.”
Dr Duke said the situation required urgent evaluation and assessment for such likely consequences.
The dieback, involving more than 7400 hectares of mangroves stretching 1000 km west of Karumba, was discovered a year ago.
The Queensland-based Carpentaria Land Council Aboriginal Corporation, with the help of TropWATER at James Cook University, is now training 19 rangers in Burketown and Normanton under the guidance of Dr Duke to monitor the situation for the eastern side.
Dr Duke said the implications of the dieback are likely to be far reaching.
“Locals are justified in their concern for possible impacts on fisheries, coastal productivity, as well as to shoreline stability and more. Losses of shoreline mangroves exposes those shorelines to severe storms and waves that could erode large sections of coastline,” he said.
Derek Barry
Editor of the North West Star Mount Isa since January 2016. Prior to that, an editor at several regional southern Queensland newspapers. Passionate about telling local stories. Comes with a strange accent to due an Irish accident of birth.
Editor of the North West Star Mount Isa since January 2016. Prior to that, an editor at several regional southern Queensland newspapers. Passionate about telling local stories. Comes with a strange accent to due an Irish accident of birth.
