The World Harbour Project (WHP), a global research programme and network aiming to enhance the sustainability of urban harbours, tested how the physical complexity of habitats effects biodiversity, by using 3D printed habitat panels.

Coastlines and harbours around the world are increasingly covered in human built structures that lack the complexity of natural habitats. This results in a major loss of associated wildlife and ecosystem functions. In some urban harbours, more than 50 per cent of natural habitats have been replaced with flat coastal defence structures like seawalls and breakwaters.

Initiated by the Sydney Institute of Marine Science, WHP published a paper researching how the surface of human built harbour structures effects biodiversity. The 3D printed panels used had different physical complexities like ridges and crevices, and were attached to the coastal defence structures at 27 sites in 14 harbours across the globe.

Panels with greater complexity generally had a positive effect on the diversity of invertebrates such as barnacles or snails. Panels with crevices of 2.5 or 5 cm deep had up to 50 per cent more marine species present as opposed to flat tiles. However, the effects of adding complexity to coastal defence structures was surprisingly variable among harbours and among different groups of organisms.

Tidal elevation and latitude greatly influenced the effect of the panel complexity. Complex habitats had greater diversity and more invertebrates at low to mid tidal elevations, and tropical and subtropical sites.

Photo: City University of Hong Kong (via New Atlas)