Working with nature for more sustainable port design; Initial findings from a 'living seawall' creation in the Port of Gladstone

The continuing development of our coastlines directly replaces, displaces or fragments important coastal habitats. This disrupts ecological services and increases pressure on coastal habitats already threatened by climate change. “Working with Nature” (WwN) approaches to coastal development may improve ecological outcomes of engineering projects and enhance the resilience of important coastal ecosystems. Restoring degraded habitats, such as mangroves, may help re-establish ecosystem services disrupted by coastal development. Practical and cost-effective WwN solutions require involvement from industry, government, and other coastal planners. To this end, the creation of mangrove habitat as part of a living seawall bordering a reclamation area in the industrial port of Gladstone, adjoining the Great Barrier Reef World Heritage Area, is being investigated. Our research examines methods for mangrove recruitment, both natural and facilitated, on newly terraformed sediment banks, which can be used to create a cost-benefit analysis of the different methods when scaling up for larger projects. This paper presents preliminary findings of mangrove habitat creation on a living seawall, using three different treatments (natural recruitment, transplanted Rhizophora stylosa saplings, and bamboo straw to trap mangrove propagules and retain sediment). This research will help facilitate the scale-up of coastal restoration and contribute to the knowledge base of coastal restoration practices by improving understanding of key coastal species.