Dendronephthya australis, an Endangered soft coral primarily found in the central coast region of New South Wales (NSW), Australia, is in rapid decline. The largest known aggregations are located within the Port Stephens estuary, where the populations have been mapped in detail via towed video at four-year intervals since 2011. Since the distribution was initially mapped in 2011, the areal extent decreased by 67.5%, and is now 9300 m² compared to 28,600 m² in 2011. Forest-based Species Distribution Models (SDMs) determined that the primary variables associated with the presence of D. australis (including depth, current velocity, slope, and the distance from the estuary mouth and the shoreline) remained largely unchanged suggesting an alternative cause of declines. General Linear Models (GLMs) identified that losses were associated with distance from shore, and change in depth and current velocity from 2007 to 2018. As these three variables are linked to sediment mobilisation within the estuary, this process is likely to be a key contributing factor to the decline of D. australis – this is supported by in situ observations over the same time period. As Port Stephens is a hydrodynamically complex environment, and has a wide variety of both commercial and recreational uses, other, as yet unidentified, processes may also be contributing to soft coral loss. The only remaining aggregations are found in depths of 4–11 m, which makes them highly vulnerable to fishing and boating impacts, as well as severe storm events.

Dendronephthya australis是一种濒临灭绝的软珊瑚，主要在澳大利亚新南威尔士州（NSW）的中部沿海地区发现，目前正在迅速减少。自2011年以来，已知最大的集合体位于史蒂芬斯港河口，通过拖曳视频以每四年一次的间隔详细绘制了人口图。自2011年首次绘制分布图以来，面积减小了67.5％，并且现在为9300 m ^2，而2011年为28600 m ^2。基于森林的物种分布模型（SDM）确定主要变量与存在的D. australis有关（包括深度，当前速度，坡度以及距河口和海岸线的距离）基本保持不变，这表明出现下降的另一种原因。通用线性模型（GLM）指出，损失与距海岸的距离以及2007年至2018年的深度和当前速度的变化有关。由于这三个变量与河口内的泥沙动员有关，因此这一过程很可能是关键因素D. australis下降的因素-这在原位得到了支持同一时间段内的观察结果。由于斯蒂芬斯港是一个流体动力学复杂的环境，具有广泛的商业和娱乐用途，其他（尚未发现）过程也可能导致软珊瑚的流失。仅有的剩余聚集体位于4-11 m的深度，这使它们极易受到捕鱼和划船的影响以及严重的风暴事件。