Living Seawalls: Boosting biodiversity through eco-engineered marine habitat design

Who Professor Melanie Bishop from Living Seawalls

What The Living Seawalls project transforms marine constructions into thriving habitats using modules shaped to mimic natural shoreline features. In Sydney Harbour, these attracted 115 species — 20 per cent more than plain seawalls. The research provides evidence for eco-engineering worldwide, showing how marine infrastructure can enhance biodiversity, water quality and climate resilience.

Winner of the 2025 NSW Department of Climate Change, Energy, the Environment and Water Eureka Prize for Environmental Research.

The Living Seawalls project is very practical and has already had real world impacts here in Sydney. Can you share some of the results of the project to date?

Since the inaugural installation under the Sydney Harbour bridge in 2018, Living Seawalls panels have been installed at over 35 sites on 5 continents. The accompanying monitoring and evaluation has revealed that Living Seawalls panels support up to 3 times the biodiversity of flat surfaces of similar material type and age. At McMahons Point, Sydney Harbour over 150 species utilise Living Seawalls panels, ranging from the shellfish that encrust the panels, to seaweeds growing in their moist microhabitats, to fishes that use the panels for feeding and sheltering. In Milford Sound, Wales, Living Seawalls panels increased growth of seaweeds on seawalls by over 90%.

What is the science behind the Living Seawalls project?

Living Seawalls builds on over 20 years of research by ourselves and others, documenting the growing extent and impact of marine construction. This research found that marine constructions (such as seawalls) support distinct ecological communities - often characterised by reduced native biodiversity and more non-native species – compared to the shoreline habitats they replace as well as their closest natural analogue, rocky shores. The ecological impacts of seawalls arise both from their destruction and degradation of natural habitats, but also their flat and often featureless surfaces, which provide little protection to marine life from predation and environmental stressors. Through small scale experiments replicated at 27 sites globally we showed that the addition of protective habitats to seawalls enhanced their biodiversity. This provided the evidence base for scaling up – through Living Seawalls.

How did this project come to life?

Living Seawalls came from a growing frustration that despite the rapidly increasing impact of marine constructions, and an established scientific evidence base supporting ecological enhancement, the research was not being translated at scale. Through the World Harbour Project – a precursor to this project – we had the pleasure of meeting award-winning industrial designer, Alex Goad. We quickly realised that Alex spoke our language and shared our vision and so we approached him about ways we could scale the approach. With Alex, our team of ecologists came up with a modular approach whereby panels of different designs could be interlocked in mosaics. The beauty of the modular approach was that it enabled installations to be customised according to environmental goals and conditions, and to be scaled up or down depending on the size and shape of the structure. The aesthetics of the arts-meets-science approach also appealed to the public, providing an ideal medium with which to communicate about the marine life of our coastal cities – where most of the world’s population experiences the ocean for the first time. Living Seawalls was born.

In your acceptance speech, you spoke about some of the challenges you have faced trying to get Living Seawalls off the ground. What difficulties did you come up against and how did you overcome them?

When you try something new and different there is always scepticism. Will it work? Will there be unintended consequences – damage to the seawall, or encouragement of pest species, perhaps? Is it allowed and what kind of permissions are need? Consequently, from conception to implementation, our first installation took well over a year. In the end it was champions, sympathetic to our cause, that got us over the line. In particular, we’d like to single out Ashraf Doureihi – an engineer at North Sydney Council – who made things happen when others said it was too hard. Initially Ash’s role was in securing land-owner consent for our first installation, in North Sydney Council LGA. However, this role quickly turned to advocate and educator, working with other Councils to help them navigate approval pathways, and commissioning sculptors to produce interpretive signage that has served as a gold standard for science communication. Unsupportive policy and management frameworks, however, remained a key challenge. Through a meeting with then Minister for Planning, Rob Stokes, we were able to have Living Seawalls classified as maintenance works, paving the way for a smoother pathway of implementation. Partnerships with community advocates were also essential for growing the program. For example, the Harding Miller Foundation and the Lim Sutton initiative, founded by passionate environmentalists, lobbied their local government for installations and arranged community consultations that helped to build public support. Sydney by Kayak fundraised for new installations and educated the public about building for nature on their corporate paddle tours.

What is next for Living Seawalls?

Early Living Seawalls installations focused on retrofit of existing marine constructions, which already harden over 50% of the shoreline of our coastal cities. However, with the number of new marine constructions rapidly growing, there is need for ecological considerations from the design phase. We are now working with partners such as DP World to explore scalable approaches for casting geometries into new constructions. We are also exploring how the provision of complex habitat geometries can be coupled with other strategies, such as the enhancement of light to shaded environments, to optimise outcomes. Seawalls are just one of many types of built structures impacting our marine environment. We are adapting our approach to other types of marine constructions, such as pilings, breakwaters and revetments. Our vision is that all new marine constructions are co-designed for nature and people.

What does winning a Eureka Prize mean to you?

We are incredibly humbled to win this award amongst a strong field of equally deserving recipients. The award is validation for the long hours chasing permissions, counting oysters and barnacles in sometimes murky urban waters, and convincing people that eco-friendly marine constructions are just as important to invest in as coral reefs. The award celebrates the work not only by our team, but also the many staff, students and interns that have contributed to the project over the years. This honour is also a testament to the giants on whose shoulders we stand on – such as Emeritus Professor Gee Chapman who was an early pioneer of marine ‘eco-engineering’.

The Australian Museum Eureka Prizes are the country’s most comprehensive national science awards, honouring excellence across the areas of research & innovation, leadership, science engagement, and school science.