Guest blogger Hannah Bourne-Taylor sets out the precarious plight of cavity nesting birds in the UK, as she urges us all to act now and save them from national extinction…
Four species of cavity nesting birds (the common swift, house martin, common starling and house sparrow) are on the red list of highest conservation concern, a term defined by the need for ‘urgent action’.
Together with leading scientists and sustainable building assessors, I created The Feather Speech, a national conservation campaign with a petition at its core. We’re asking the Government to make swift bricks compulsory in new housing across Britain to help safeguard these species from becoming nationally extinct.
Cavity nesting birds and the loss of nest sites
Since 2002, when house sparrows and common starlings were added to the red list, scientists have raised loss of nest sites as a possible factor for the decline of these cavity nesting birds (BTO Research report No 290 2002).
They’re aware that modern buildings contain fewer nest sites for birds, and that those in old buildings may be being destroyed (Moss 2001).
This year’s government ECO+ Scheme has already made 2.4 million homes more energy efficient thanks to insulation measures, including roof and wall insulation such as soffits. However, this will further negatively impact cavity nesting birds.
The loss of nest sites for swifts is a particular concern because these birds are site loyal, as adults return to the exact nesting site year-on-year for their 20-year lifetimes. With one of the shortest breeding seasons of any bird, the individual pairs often return to find their nests blocked off. They therefore risk being unable to find a new cavity to nest and breed in, thus contributing to a population decline of more than 50% in the past 20 years (BTO). Many individuals fatally break their wings trying to get back into their nesting sites, after nine months on the wing.
Swifts are almost entirely dependent on having access to our walls to breed in. They used to nest in tall trees in forests – some colonies still remain in the primal forests of Europe, but we cut the trees down here. These remarkable birds, from one of the most ancient orders of birds dating back 70 million years, adapted to live alongside humans in walls and other built structures.
Current policy on cavity nesting birds
In the Netherlands, the nest sites of swifts are legally protected all year round. Loss of nest sites during renovation work is compensated for by the installation of either nest boxes or swift bricks.
Meanwhile, in the UK, no such protection exists. However, the Government does recommend that Local Planning Authorities (LPAs) make swift bricks compulsory in new housing developments. Swift bricks, also known as ‘universal bricks’ because they provide nest sites for a diversity of species, are house bricks with a special cavity that sit flush to the wall.
They’re recommended in the Design Codes Guidance for local authorities, ready for the implementation of the Levelling-up and Regeneration Bill.
There is national best-practice guidance on the use of swift bricks in the form of BS 42021:2022, in addition to CIEEM. This standard recommends one nest brick per dwelling on average for new-build housing developments. The value of swift bricks to wildlife is highlighted by National Planning Policy Guidance (Natural Environment 2019 paragraph 023).
As an example, swift bricks have been installed across the Duchy of Cornwall estate, and are monitored by the RSPB.
Many LPAs mention swift bricks in their guidelines for Local Plans but only some have made swift bricks a compulsory condition for new housing, including Brighton and Hove, Cambridge, Edinburgh, Hackney, Sutton, Basildon and South Hadden.
With new Biodiversity Net Gain (BNG) provisions, developers are unlikely to include swift bricks. As they’re not part of BNG, there’s no incentive for this crucial biodiversity measure to safeguard cavity nesting birds. Despite clear recommendations, the installation of swift bricks is not common practice.
Mitigation for cavity nesting birds
I’m pursuing the need to follow the Netherlands’ policy on cavity nesting birds to ensure there is mitigation for loss of nest sites and raise awareness of the destruction of cavity nest sites as a direct result of the ECO+ Scheme.
Extensive case studies collected by the Swift Local Network (made up of local swift conservation groups) record nesting sites and swift numbers. This collection gives localised examples of nest sites being destroyed, breeding pairs of swifts being displaced, but also of swift-brick installation being a success, which often increases the original local population size.
On a larger scale, Wakefield and District Housing has collaborated with a local swift group, while undergoing the installation of soffits, by placing 440 holes and nest cups in the space above each soffit.
In contrast, the external wall insulation (EWI) programme in Dundee is targeting 740 properties – and inadvertently the destruction of a colony of swift’s nesting sites – and has no such plan, despite requests from local swift conservation groups to mitigate the loss of nesting sites.
Our hope for cavity nesting birds
A nationwide policy for either swift bricks in new developments, and/or the mitigation of destroyed nesting sites linked to the ECO+ Scheme, would make the effort to help these four red-listed cavity nesting birds efficient.
Please sign the petition and, if you can help this campaign achieve its goals, then get in touch with me on the campaign email: thefeatherspeech@gmail.com.
Time is of the essence. My biggest concern is that these birds are not being considered, despite being our closest wild neighbours.
Find out more
- Email Middlemarch for an initial conversation about your own species-protection and how we can help at hello@middlemarch.eco.
- Visit Hannah’s website at https://hannahbournetaylor.com.
