A turtle dove, sitting in a tree.

In the run-up to Christmas, it is saddening to hear that turtle doves may soon be found only as references in Christmas carols.

In September 2023 the State of Nature Report was published. Compiled by over 60 research and conservation organisations, it uses the best available data to quantify the state of the UK's biodiversity concerning towns, cities, countryside, and seas.

The challenge

Despite progress in ecosystem restoration, conservation efforts, and moving towards more nature-friendly land and sea use, we are witnessing a continuing decline. One in six of the 10,000 species studied are now at risk of becoming extinct, and on average species numbers have declined by 19% since 1970.

We have also been warned of the risk of ecological chain reactions triggered by losses in insects, fish and plants which are key components of food chains, some of which also provide vital ecosystem services such as pollination and pest control.

Causes for these losses include a lack of available food, lack of habitat, climate change impacts and pollution.

Based on data from the Biodiversity Intactness Index, the UK is in the lowest 5% of 240 countries. The UK’s nature has been depleted by centuries of habitat loss, and industrial and agricultural development and now has less than half (42%) of its biodiversity remaining due to human activity.

By thinking more collaboratively and creatively about how we protect the UK’s nature rail can be part of the solution, rather than the problem, ensuring that species like the turtle dove, will be around for many more Christmases to come.

Nick Cork, University of Birmingham

In addition, most (86%) of the important habitats for the UK’s nature (including 93% of woodland) are currently in poor condition. Despite overall increases in woodland cover, woodland wildlife is decreasing due to fragmentation, habitat degradation and the lack of woodland management such as coppicing.

In our cities and towns, biodiversity, tree cover, clean air and clean water are threatened, with unequal and diminishing access to good quality green spaces, hitting the most economically deprived areas the hardest.

How rail can be part of the solution

It's not all doom and gloom though. The report highlights that the solutions to these challenges are known and projects to restore important habitats such as woodland, wetland and peatland are underway. However, to successfully halt and reverse biodiversity loss, urgent and widespread action is needed across all sectors.

As part of the UK government's 25-Year Environment Plan, Defra and Natural England have created the Nature Recovery Network (NRN) which aims to create, restore, and enhance wildlife-rich places and to connect these with corridors and stepping-stone habitats to help wildlife populations grow and move. Research suggests that the “green infrastructure” found alongside road and rail corridors can provide habitat connectivity within a fragmented landscape such as the UK, and this is echoed in the 2018 Varley Report. Wildlife underpasses and green bridges also attempt to address the risk of wildlife-vehicle collisions.

The Cambridge Centre for Science and Policy (CsaP) advise that if the UK is to realise its ambitious targets set out through the Global Biodiversity Framework agreed at COP15 (including the 30 by 30 pledge), coordinated efforts and investment are required. Even though 26% of UK land is designated as national parks or areas of outstanding natural beauty, Wildlife and Countryside Link estimate that only 3.2% of land and 8% of the sea is well protected and managed for nature. Part of the challenge will be to break down stakeholder 'silos' and to address the challenge in a multidisciplinary way, addressing the fact that the climate agenda and biodiversity crisis are intrinsically linked.

It is within this context that our team at the University of Birmingham’s Resilient Systems and Climate Action research group is working with Network Rail to research biodiversity net gain and ecological connectivity along the UK’s railways.

Network Rail owns over 30,000 kilometres of track and its land boundary encompasses around of 6 million trees. Our research aims to challenge the ’stakeholder silo’ mentality by incorporating the NRN and publicly available datasets to map potential ecological corridors and stepping-stone habitats onto the UK rail network. This will help us to understand which sections are likely to be important for landscape scale ecological connectivity, known as “hotspots”.

Hotspot areas will then be selected for detailed analysis to determine corridor vegetation “quality” and permeability for dispersal. Using this as a baseline, methods and tools will be developed to optimise connectivity whilst considering risk to other railway systems.

With this research we hope to contribute to the effective targeting of investment into nature recovery and a resulting upturn in biodiversity metrics, signalling the recovery of the state of the UK’s nature. By thinking more collaboratively and creatively about how we protect the UK’s nature rail can be part of the solution, rather than the problem, ensuring that species like the turtle dove, will be around for many more Christmases to come.