Due to its profound alterations in land use and cover, urbanization is widely recognized as a major driver of biodiversity loss. Despite this, recent research on biodiversity in cities and urbanized areas has highlighted that a considerable number of regionally occurring and endangered species are present in urban environments, demonstrating that cities hold promising, yet often unused, potential for biodiversity conservation. To harness this potential, promoting the presence of coarse wood debris, also known as deadwood, is essential. Because of its role as breeding, feeding, and living spaces, deadwood is frequently utilized by various species, such as cavity-breeding woodpecker and tit species. In cities, however, deadwood is usually a scarce resource due to the scarcity of old trees and strict management practices that often lead to the immediate removal of deadwood that may pose a safety hazard or not contribute to aesthetic appeal. 

To provide suitable living, feeding, and breeding spaces for a variety of deadwood-dependent species, the project combines established methods and knowledge from urban ecology with recent advances in 3D-printing technologies and fungal biotechnology by developing substitute structures consisting of wood-mycelium printing mixtures (WMPMs) using liquid deposition modeling.

The project follows three steps of research:

WP1: Development of insect hotels and simple microhabitat substitute prototypes using WMPMs. These are then distributed across the city of Munich for 18 months, allowing the monitoring of material development and species acceptance. 

WP2: Measurement of material features (e.g., inside-humidity) of WMPM prototypes. Incorporating the results allows further refinement of printing parameters, WMPMs, and post-processing of prototypes.

WP3: Upscaling of 3D-printed prototypes to provide suitable substitute structures for cavity-nesting birds. These prototypes will again be tested in the field.