September 24, 2021

I, Science

The science magazine of Imperial College

In the second part of our series on green cities, we make the case for keeping wildlife at the forefront of our sustainability efforts.

grey squirrel with city skyline in the backgroundFor city dwellers, wildlife encounters are rare. Perhaps confined to tripping over a pigeon as it pecks at a pizza crust, or being jolted awake by a pair of foxes in the throes of a territorial dispute. It’s easy for urbanites to lose sight of the importance of maintaining wildlife habitats in highly-developed zones, which present a unique and increasingly vital conservation opportunity.

When wildlife must compete with people for resources, humankind never loses. Habitat destruction and fragmentation, obstructed migration corridors, and vehicular collisions are among the most obvious impediments that make cities inhospitable to wildlife. More insidious impacts, such as noise and light pollution and exposure to toxic runoff, amplify the declining numbers and diversity in existing wildlife populations. Rapid spread of disease and competition for essential resources limit mating potential, preventing new populations from colonising cities. The result? Shrinking regional biodiversity catalysed by a weakening connection between humans and in a city

If city parks bereft of birdsong are not reason enough to bolster urban wildlife habitats, consider the ecosystem services animals perform in our cities. While raccoons rummaging through your bins might make a mess, these, as well as other scavenging animals, serve as a means of green waste management. Working up the food chain, birds and snakes prey on insects and rodents, controlling populations which could transmit disease to humans.

Maintaining these natural systems of waste, pest, and disease control requires suitable habitats, especially in areas of high population density and development. So what came we do? ‘Wildlife gardening’- cultivating indigenous plant species in order to replicate an area’s natural structure and resources – attracts native birds and insects, promoting ecosystem health and development through pollination.

purple coneflowers

The London Wildlife Trust (LWT) aims to promote the development of wildlife-friendly green spaces at the ‘grassroots’ level. Its current initiatives are numerous, with projects underway in boroughs across London. LWT members created the Cressingham Rain Gardens, a ‘green corridor’ consisting of three connected gardens designed to support habitat for birds and insects. De-paving initiatives, such as the one at Rosendale Allotments, encourage people to replace impermeable surfaces such as paved driveways with native vegetation. The trust has also run green roof workshops, demonstrating how easy it is to transform the rooftop of a shed into a micro-habitat.

As Sophie Walsh discussed in part 1, an increasing number of cities are jumping (thankfully) onto the sustainability bandwagon, but with towns and cities the world over become increasingly populated, it is up to us to ensure that our wonderful wildlife does not get swept under the urban carpet in the process.

Erin Frick is studying for an MSc in Science Communication

Images: pigeon, Furtseff; squirrel, Kollar Peter; fox, Jamie Hall; flowers, ileana_bt.