Gustav Creek

Gustav Creek is the major watercourse of Nelly Bay. Its catchment area is over 500 hectares, which is one of the largest catchments on Magnetic Island. It is also the only semipermanent water body on the Island but in very dry years it, too, stops.

The creek is over 3.5 km long and follows a relatively steep slope of over 15 degrees throughout most of the catchment. On some very steep slopes landslides have occurred, the scars of which remain visible on the hills. As Gustav Creek makes its way down from high in the hills it passes through steep boulder country, gravelly foot slopes, finer alluvial sands and finally beach ridges or sand dunes.

Throughout this journey Gustav Creek recharges the groundwater and local aquifers and delivers sand from the catchment to replenish Nelly Bay beach. Gustav Creek also provides a wildlife corridor from the uplands through the lowlands to the marine environment, which is crucial to much of the bay's wildlife.

Gustav Creek map

High Resolution map (1.2MB! .pdf)

Alexandra Palms (Archontophoenix alexandrae)

The vegetation in the Gustav Creek catchment is quite complex and at least ten vegetation communities have been identified. This makes Gustav Creek critically important in maintaining the biodiversity of this unique dry tropical environment. One of the unique communities is the vine forest that is almost a 'wet tropics rainforest' in the upper catchment. This community is still in a pristine state and includes a tall stand of alexandra palms (Archontophoenix alexandrae).

The lower estuarine area of Gustav Creek has changed over the years. Historically the lower reaches of Gustav Creek would have been an open dry tropical woodland and savanna grassland, but now due to a lack of fire in the lowlands most of this area is now a vine forest with qualities more similar to the wet tropics than the dry tropics.

Despite significant loss of coastal vegetation to development, the mangroves you see here have flourished since the breakwater was built as part of the works associated with the harbour development. These mangroves are important for filtering excess nutrients and fine sediments before they enter the waters of the Great Barrier Reef.