Property developers installing as few as half of promised ecological features – new report

The UK is currently one of the world’s most biodiversity-depleted countries. Urbanisation is a known driver of the nature crisis. This means that the planning system, which regulates development in the UK, plays a crucial role in protecting nature from harm.

On paper, things look positive. Over the past 20 years, a growing list of international, national and local laws and policies have been passed to ensure that the planning system protects ecologically sensitive sites. In spring 2024, England’s new biodiversity net gain policy came into effect, requiring all new residential developments to achieve and maintain a 10% increase in biodiversity, secured for 30 years.

In practice, this means that when developers seek planning permission to build new housing, they have to conduct ecological surveys of their proposed site. The local planning authority reads these reports and lists a set of planning conditions, which are binding: in theory, the developer must adhere to them. This includes providing habitat for wildlife on the land used for development, minimising the harms to nature associated with the change of land use, from farmland to urban areas, for example.

However, in the summer of 2024, we audited 42 new developments across five local planning authorities in England to see whether developers were complying with these ecological conditions on the ground. We found just 53% of the ecological features that should have been there were actually present. When we excluded street trees, this fell to 34%.

Our report, which has not yet been peer reviewed, was commissioned and published by Wild Justice. This not-for-profit environmental campaigning organisationwas co-founded by broadcaster Chris Packham, author and conservationist Mark Avery and Ruth Tingay, a columnist who campaigns against raptor persecution – their work is funded by public donations. We wrote the report together with Sarah Postlethwaite, a senior planning ecologist who works for a local authority.

To research every site, we downloaded relevant documents from each council’s planning portal, including landscaping maps. We visited every street and public open space within each development and measured whether the planning conditions had been met on the ground. We walked over 291 hectares of land, surveyed nearly 6,000 houses and searched for 4,654 trees and 868 bird boxes.

More than half (59%) of wildflower grasslands were sown incorrectly or damaged, and 48% of hedges were missing, along with 82% of specialist woodland edge grassland.

Statistics were even worse for species-specific mitigations: 83% of hedgehog highways were absent, along with 75% of bird and bat boxes. Some swift and bat boxes had even been installed upside down, making them useless to their intended occupants.

This pattern was surprisingly similar across the country, for all sorts of property developers, sizes of development and location. Given that we looked at many local, regional and national housebuilders, this strongly suggests a systemic issue across the planning and development system.

Lack of enforcement

So why is this happening? One simple reason is a lack of effective regulation. Planning consents are supposed to be enforced by specialist teams in local planning authorities.

Ideally, they would visit every new development and do similar checks, but enforcement budgets have been subjected to severe cuts since 2010, leaving them unable to deal with anything but the most serious breaches. Assessing the presence of ecological features also requires a specialist skillset that most people working in planning enforcement do not have. Alongside a resources problem, there is a skills and knowledge gap that needs to be filled.

But there’s also something more worrying going on. The planning system is focused on the processing of applications, paying little attention to the “concrete” outcomes of the system, in both senses of that word.

A great deal of the private sector consultancy that surrounds ecological mitigations (that includes the work of ecologists, landscape architects and private sector planners) is about producing documents that are prospective and virtual.

Hardly any effort is spent checking up on whether any of this activity equates to outcomes on the ground that genuinely help the natural world. With nobody checking whether conditions are met in practice, developers can simply break ecological planning conditions, and get away with it without consequences.

How to avoid irreparable harm

The situation urgently requires action because the government recently announced a huge increase in housing targets. Their assumption is that the ecological harms associated with this level of urbanisation will be mitigated by existing ecological policy and protections. Our work shows that these systems are simply not working in practice on development sites around the country. If nothing changes, what looks like a biodiversity net gain on paper could become a loss.

The government has sought to downplay the severity of this situation, presenting housing as a battleground between environmental and social goals, between newts on the one hand and desperate victims of the housing crisis on the other But, presenting this as a direct conflict is a deeply unhelpful and old-fashioned framing. In reality, human and ecological wellbeing are irrevocably intertwined and biodiversity loss has so many hidden social costs. The key is to find affordable and effective solutions to both dimensions.

Habitat degradation is now predicted to lead to a drop in UK GDP of between 6-12% by the 2030s, a financial impact that could end up being greater than the financial crisis or COVID-19. Research suggests that delivering 300,000 homes a year would blow the entire carbon budget for England.

Other, far less environmentally harmful measures can provide a more meaningful solution to housing provision: building social housing on sites with low ecological value, retrofitting existing building stock and controlling the use of housing as an asset for investment to reduce the number of second homes would be a start.

Effective regulation is desperately needed. With the development industry making “supernormal” profits from the construction of housing, there is no excuse for failing both nature and people in this way.

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The research in this report was funded by Wild Justice, a campaigning organisation headed by Mark Avery, Chris Packham, and Ruth Tingay. Kiera Chapman's fellowship at the University of Oxford is supported by the National Institute for Health and Care Research (NIHR) Oxford Health Biomedical Research Centre (NIHR203316). The views expressed are those of the author and not necessarily those of the NIHR or the Department of Health and Social Care. Kiera is also Co-Investigator on the ESRC-funded 'Planning for Nature' project (ES/Z503459/1).

Malcolm Tait receives funding from the Economic and Social Research Council. He is Principal Investigator of the ESRC-funded 'Planning for Nature' project (ES/Z503459/1).