"Cities need to learn how to better protect and enhance biodiversity, because rich biodiversity can exist in cities and is extremely critical to people's health and well-being," said Professor Thomas Elmqvist of the Stockholm Resilience Centre and Scientific Editor of the report.

The Cities and Biodiversity Outlook highlights a wide range of successful initiatives by cities, local authorities and sub-national governments in both developed and developing countries.

In Bogotá, Colombia, measures such as closing roads on weekends, improving the bus transit system and creating bicycle paths resulted in increased physical activity among residents, and a reduction in greenhouse gases emissions.

The report also provides detailed analyses of regional urbanization trends and their impact on biodiversity and ecosystems.

The Cities and Biodiversity Outlook demonstrates how urban areas can play a central role in achieving 20 key biodiversity goals (known as the Aichi Biodiversity Targets) which were agreed upon in 2010 by parties to the Convention on Biological Diversity.

For example, the restoration or 'greening' of ex-industrial sites or brownfield land by city authorities can support efforts to achieve Aichi Target 15, whereby 15 percent of degraded ecosystems are restored by 2020.

Cities can also help prevent extinction of known species (Aichi Target 12) through research and investment by zoos, aquaria and museums, many of which are managed by city authorities.