Nature can thrive in cities with the right opportunities, and some English councils are working to help develop homes for wildlife within new buildings.
New planning laws in Brighton and Hove now require developers to install "bricks" for bees and swifts into all new buildings taller than five metres. These are hollow bricks with an entrance hole for birds, or bricks with lots of small holes to allow tubes for nesting bees. Hackney Council has adopted rules requiring new build projects to include swift bricks.
Both swift and bee bricks can be incorporated into the brickwork of a new home. Swift bricks are designed to be barely noticeable to the homeowner but provide gaps to allow safe nesting areas. They don't just provide homes for swifts - other species of birds, and even bats, may take up these new residential opportunities. Bee bricks allow solitary bees to nest and, as their name suggests, these species do not live in colonies and are not aggressive in protecting their nests.
Questions have been raised about whether these bee bricks could spread disease and parasites, but this has yet to be studied and it is likely that bees will avoid nesting in sites with high parasite loads. To be effective, bee bricks need to be properly designed by considering the bees general ecology and nesting requirements. Bees naturally assess whether a hole is appropriate for them, and any risks it presents.
Bricks as homes
Bee bricks in sunny spots will get used in most places as long as there are the habitats there to support them (gardens with insect-friendly plants), but swifts can be a little bit harder to encourage. The adult birds go back to the same nesting spots each year, and to persuade them to take up new areas, you need to play their screaming calls to attract their attention as the breeding season begins. Even if swifts don't take up these hollow bricks, they can be used by other species such as starlings, great tits, as well as some species of bat.
The swift actually only spends a few months visiting our shores, arriving just in time to breed before heading back to Africa - in a journey they complete without ever stopping, as they feed and sleep in flight. For many of these birds, their arrival may be met with disaster. Swifts nest at the same site each year, meeting the same mate there before starting breeding - and often renovation works mean the nest entrance has been sealed. Their numbers have plummeted by 58% in the 23 years between 1995 and 2018 (the latest year for which we have data). Our pollinating invertebrate species, including solitary bees, are also suffering devastating losses - and they are not the only examples.
Threats to the hedgehog and sparrow
Many of the UK's best loved species are in decline, including some that share our gardens and local parks. Species such as the once-common house sparrow are now at high risk of extinction, as are the swift and house martin. Gardeners' friends such as the hedgehog and toad are slowly disappearing, and groups of less well known species like solitary bees are also in decline.
We should continue to look at which other measures will have the biggest positive effects for nature. This could be as simple as ensuring that trees and hedgerows are maintained and that native planting is used in gardens and green spaces.
These new bricks are a step in the right direction, but councils can do more to encourage developers to build sustainably and in nature-friendly ways. Making space for wildlife is just as important for our own health and wellbeing. Spending time in nature can affect your physical and mental health and reduce stress and loneliness.
Thousands of people already make a huge difference. Feeding of birds in winter, bug hotels (where insects can live), and bird nesting boxes are the main ways that people support their garden wildlife. There are also many other ways for the public to provide spaces to support the natural world, even if it doesn't involve bee bricks. Helping garden birds and frogs and toads is relatively easy.
Read more: Urban bee keepers can help save wild bees
Until recently, developers did not have to consider nature in their plans for new housing. But the government has set out the biodiversity net gain proposals to ensure that new developments have more natural spaces. This may start to change the way developments are designed.
So let's hope that councils adopt more policies to help encourage and support wildlife, especially where species are struggling.
Author: Becky Thomas - Senior Teaching Fellow in Ecology, Royal Holloway University of London