Hedgehog survey helper plea
A world-first combination of people power and technology will take hedgehog conservation to a new level, Athwenna Irons reports
THE National Hedgehog Monitoring Programme (NHMP) has been launched to estimate the sizes of hedgehog populations across the country.
The survey also aims to show how the numbers are changing year on year, and, in time, give a national estimate of Britain’s hedgehog population. The three-year pilot project uses sophisticated, state-of-the-art artificial intelligence (AI), a worldfirst in hedgehog conservation.
Led by wildlife charities the British Hedgehog Preservation Society (BHPS) and People’s Trust for Endangered Species (PTES), in partnership with Nottingham Trent University, ZSL’s London HogWatch, Durham University and MammalWeb, and largely funded by Natural England, this unique combination of AI, trail cameras and home-based volunteers will aim to produce crucial insights into the factors causing hedgehog populations to plummet, and enable conservationists to implement practical conservation measures to try to reverse the decline.
According to the State of Britain’s Hedgehogs 2022 report, published by BHPS and PTES, rural hedgehog populations have declined by between 30 and 75% across different areas of the countryside since 2000.
Dr Henrietta Pringle, National Hedgehog Monitoring Programme coordinator at PTES, said: “For the first time in the history of hedgehog conservation we’re using AI to open up new opportunities, which is extremely exciting. Previous studies have estimated hedgehog populations, but there has never been a rigorous nationwide survey of them until now.
“We know hedgehogs are struggling, especially in the countryside, but before we can put practical conservation measures in place we need to understand where they are and why they’re declining. This is the first study where populations are measured year after year, in the same location, which will produce vital data and allow us to identify those at risk, which in time will hopefully help us to reverse the decline.
“The results will also allow us to see regional and habitat differences, and identify what factors impact them in different places, which will not only be fascinating but also incredibly useful for their long-term conservation.”
The NHMP uses trail cameras to capture images of hedgehogs (and other wildlife) in different habitats, including urban parks, private gardens, woodlands and farmland. AI algorithms sort all the images captured, minimising the numbers of blank or human images, and maximizing the number of animal images for home-based volunteers – known as ‘spotters’ – to identify.
Once the images are classified, a team of analysts can produce vital population numbers and information. The algorithms have been developed by Conservation AI, machine learning specialists based at Liverpool John Moores University.
Volunteers from all corners of the UK are needed to make the project a success and can take part from the comfort of their own homes. Last year trail cameras were placed at 13 different sites across the country, from Dorset to Glasgow. A total of 30 trail cameras were placed at each site and were left in situ for a month, generating thousands of images, with the species in these images then needing to be identified. Fay Vass, chief executive of the British Hedgehog Preservation Society, said becoming a ‘spotter’ for the National Hedgehog Monitoring Programme is a fantastic way for everyone to get involved. “Everyone loves hedgehogs, but we recognise that not everyone is in a position to help them in the wild,” she added.
“Now, those with mobility issues, who don’t have a garden or perhaps are away studying at university or college, can help from the comfort of home. Helping hedgehogs has never been easier or more accessible, so we really hope people from all walks of life take part.”
The NHMP team, with the help of a pilot group of volunteers, has started the enormous task of checking the images from the 13 sites surveyed in 2023. Hedgehogs have been spotted at six of them so far, and many other interesting species, such as tawny owls, stoats and red squirrels have also been seen.
Over the three years of the NHMP’s pilot, the team will place cameras at an increasing number of sites across Britain. The ambition is to have surveyed 40 sites by the end of the trial, which should produce enough data to derive a more accurate estimate of the numbers of hedgehogs in the different habitats surveyed, and give a robust national estimate. Going forward the existing sites will be monitored annually, and new sites added.
To sign up and become a spotter, visit the website www.nhmp.co.uk where free training and identification guides are also available.