Long Point saltmarsh recovery in Tasmania continues to amaze!
We recently took another trip to the edge of Moulting Lagoon, on Tassie’s east coast, in November 2024. The purpose was to continue to monitor the ecological recovery of saltmarsh in response to restored hydrology at the Tasmanian Land Conservancy’s Long Point Reserve and the adjacent private property, ‘The Grange’. Restored areas of wetland and saltmarsh are continuing to rapidly regenerate and adjust to their new water regime, now that we are between 18 months and up to two and a half years post-works. This update builds on previous information about the recovery of this site posted earlier this year (see our April 2024 update on the site). Below we’ll visit a few different areas of Moulting Lagoon, and compare the progress since restoration works began in 2022.
Yards Hole, The Grange
The perimeter of Yards Hole continues to consolidate, as the wetland now has a reinstated seasonal water regime. The rehabilitated shoreline continues with its spontaneous recovery, becoming covered in local native vegetation including saltmarsh and grassland species. The previous channel and impoundments to the north of the wetland have been long forgotten, their presence barely discernible two and a half years on.
L-shaped Perimeter Drain, eastern Long Point Reserve
The L-shaped drain footprints continue to be spontaneously colonised by saltmarsh species, some faster than others, but we must remember these areas have been buried under spoil heaps for nearly 200 years! It’s going to take a little longer for these areas to regenerate to 100 % cover but the progress so is extremely pleasing.
Opening Hole and Barkstand, Long Point Reserve
Given the short time that has elapsed since works were completed in autumn 2023, the regeneration of saltmarsh around the perimeter of Opening Hole and on the old Barkstand channel is astounding.
The re-exposure of the original saltmarsh surface (the black mud shown below) from beneath the spoil of the former drain at Barkstand, which at this location was only buried for 30 years, has been much more complete and rapid than the much longer buried eastern levee described earlier. This evidence appears to support NGT’s assumption that a residual seed bank within the buried surface would help to accelerate saltmarsh recovery.
The images below are before and after shots, 18 months apart.
A little further west along the former Barkstand drain, and the pattern of rapid recovery is the same.
Within and around Opening Hole itself, patches of bare mud, which were widespread due to an elevated water level of artificial frequency in this wetland (due to the hydrological impact of the former channel letting in the tides) have given way to bright green, new succulent saltmarsh species. I wonder if the Gahnia tussocks will start to move back into this area, after years of observed dieback? The water regime of this wetland has changed markedly post works with the wetland now being able to be filled less frequently (mostly by local rainfall) and then naturally recede during summer/autumn dry periods. The wetland was completely dry during April and was receding during our December trip.
The remediated drain along the margin of Opening Hole, shows the same trend of saltmarsh recovery.
Large areas of bare ground as a result of bulk remedial earthworks undertaken at Barkstand, especially within the spoil placed back into the drains, were colonised early on by thistles. A similar theme and order of progression was witnessed along the margins of Yards Hole 2.5 years ago. However, even over the past six months (as shown above) these areas are gradually reducing, as these weeds are tackled in a competition for space on both sides, by regenerating saltmarsh and rush communities. It will be important to observe how these areas continue to regenerate into the future, as early, often exotic, colonisers give way to natural, endemic species that have the upper hand to outcompete in the harsh saline conditions of saltmarsh and lagoon habitats.
We look forward to continuing to monitor and observe the outcomes of restoration works conducted at The Grange and Long Point over time, in conjunction with our project partners.
Nature Glenelg Trust delivered this important project, thanks to support from NRM South and the Tasmanian Land Conservancy, with funding provided by the Australian Government.
