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By & Havn: Reusing oyster shells to secure higher biodiversity

With fish nurseries made out of leftover oyster shells, By & Havn is improving the biodiversity of the harbours of Copenhagen.

Reusing oyster shells to secure higher biodiversity

The harbour environments of Copenhagen are among the best in the world. To help secure this, By & Havn has partnered with the World Wide Fund for Nature (WWF) to install 50 Biohuts. These work as fish nurseries, homes, pantries and shelter for the fry of more than 25 species, so that they can hide from larger predators in the most vulnerable part of their lifecycle.

The installation of Biohuts is part of a perennial agreement between By & Havn and WWF to improve fish habitats and increase biodiversity. By enhancing fish stocks and creating a better harbour environment, the Biohuts provide an immediate effect in terms of increased biodiversity and, over time, more fish, which also benefit the many anglers utilising the harbour’s 42-kilometre long quayside.

The project is a great example of how investing in nature benefits the fish population and biodiversity through a circular initiative. The Biohuts consists of a steel cage filled with leftover oyster shells gathered from oyster farms in Marseille, France. With the Biohut project, the shells are collected, disinfected and reused for new a purpose instead of being thrown out.

About

By & Havn is a development and operating company that provides long-term and holistic urban development and takes responsibility for creating coherent and well-functioning urban neighbourhoods, like Ørestad and Nordhavn. Their revenue from their different activities goes to common goods such as paying for major infrastructure projects in Copenhagen – including the metro as well as urban spaces, quays, breweries, parks and initiatives in the new urban districts. By & Havn is owned 95% by the City of Copenhagen and the last 5% is owned by the Danish government.

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