Revitalising Estuaries: Jerona Bund

Queensland Parks and Wildlife Service

Great Barrier Reef Marine Park Authority

Fishing

On-ground work, Monitoring

(none)

(not documented)

(not documented)

(not documented)

2013

Ongoing

Located in the Bowling Green National Park just west of Barratta Creek, the Jerona bund was originally constructed to allow for marginal grazing. Approximately 500 metres in length, the bund was preventing tidal inundation to large inland areas that were once saltmarsh ecosystems. The bund caused the accumulation and retention of freshwater, particularly after the wet season, which promoted the infestation of exotic weeds. Taking advantage of the modified hydrology, para grass (Urochloa mutica) dominated approximately eight hectares of the national park, along with the scattered presence of olive hymenachne (Hymenachne amplexicaulis), a Weed of National Significance; both of which favour freshwater conditions.

The weed infestation at the project site was directly impacting local plant and fish biodiversity by dominating the wetland, as well as causing a never-ending regime of weed control maintenance for QPWS.

Through the Federal Government Biodiversity Fund, directed by the Fisheries Research and Development Corporation, the site was chosen as one of two pilot projects along the east Australian coast for revitalising estuaries in order to restore fisheries productivity, biodiversity and other environmental outcomes. In December 2012 one section of the bund was removed with an excavator, opening a gap of about 5 metres to coincide with the upcoming king tide of early January 2013. The removal of the bund showed immediate success, so further earthworks were undertaken to extend the opening to 10 metres wide. At the same time, another section of the bund was removed approximately 15 metres in width. With two areas of the bund now open to the tide, the site provided for greater tidal exchange.

With the reintroduction of tidal water and the change in wetland type from an artificial freshwater system to a seasonally brackish one; conditions at the site now favour native plants over exotic weed chokes, and provide suitable habitat for range of fish species. The wetland also requires less maintenance for weed control, while the work undertaken has improved the ecosystem services the wetland provides to the downstream Ramsar wetland and the Great Barrier Reef lagoon.

The wetland will continue to improve and move towards becoming an even more naturally biodiverse and functional site, with QPWS planning to introduce fire management as part of their annual fire program, alongside the Traditional Owner group Gudjuda.

(not documented)

(none)