London — Mathew Frith, an urban nature conservationist who dedicated his life to protecting and improving access to green spaces, has died aged 64 from a glioblastoma (brain tumour). He leaves behind a remarkable national legacy of championing urban wildlife, pioneering citizen science, saving sites from development, and inspiring new generations to value the natural world.

Frith’s conservation journey began in 1989 when he joined the London Wildlife Trust (LWT). As warden of Sydenham Hill Wood from 1990 to 1995, he immersed himself in the challenges of managing an urban woodland, working closely with volunteers to restore and protect habitats.

By 2000, his expertise led him to English Nature as urban adviser, where he influenced policy through the government’s Urban Green Spaces Taskforce and helped revise national standards for equal access to green spaces. In 2002, at the Peabody Trust, he co-founded Neighbourhoods Green, a landmark £15.6 million programme that transformed life across 70 London housing estates.

Returning to LWT in 2009, Frith went on to serve as director of policy and research, deputy chief executive, and director of conservation. Beyond the trust, he shared his knowledge as a lecturer at UCL Birkbeck and advised the Commission for Architecture and the Built Environment, the Green Flag scheme, and the mayor of London’s Rewilding Taskforce. In recognition of his contributions, he was appointed MBE in 2023 for services to the natural environment.

Born in Purley, Surrey, Frith grew up in south Croydon, where his early fascination with wildlife blossomed while exploring Croham Hurst Woods and watching butterflies emerge in his family home. He studied zoology at the University of Exeter but soon turned to music, briefly touring as a guitarist with the rock band Loop in the late 1980s—though even then, friends remembered him slipping away to search for dragonflies. He later described himself as a “failed rock star” who had found his true calling back in nature through the Greater London Council’s ecology unit.

Frith never shied away from activism, often describing nature conservation as “a political act.” He fiercely opposed development threats to London’s green belt and campaigned for the preservation of Hutchinson’s Bank in Croydon and Woodberry Wetlands in Hackney, the latter officially opened by Sir David Attenborough in 2016.

Colleagues and friends recalled his delight in both the rare and the everyday: from discovering Impatiens frithii, a plant endemic to Cameroon, to celebrating the beauty of ordinary magpies. His creativity and individuality shone through in his trademark white clothing, bangles, changing hairstyles, and handwritten calligraphic postcards. In recent years, he had been pursuing an MA in nature and travel writing at the University of Bath, further refining his distinctive, lyrical voice.

He is survived by his wife, Keren Protheroe, whom he met at a Christmas craft fair and married in 2011, along with his siblings, Penny and Toby.

Mathew Frith’s life was defined by passion, wit, and a relentless devotion to the natural world. His influence endures in the landscapes he fought to protect, the communities he inspired, and the conservation movement he helped shape.