The slow worm (Anguis fragilis) is a legless lizardānot a snakeāfound widely across the UK in gardens, allotments, rough grassland, and woodland edges. Often misidentified and occasionally killed through misunderstanding, slow worms are fully protected under the Wildlife and Countryside Act 1981 and are important components of garden ecosystems.
Slow worms are secretive, heat-seeking reptiles that spend much of their time under objects that absorb warmthācorrugated iron sheets, compost heaps, flat stones, fallen timber. They are viviparous (giving birth to live young) and can live for 20-30 years in the wild. They feed primarily on slugs, making them effective natural pest controllers in gardens.
Garden machinery: Strimmers and mowers kill and injure slow worms sheltering in long grass. Checking before cutting, particularly around known shelter sites, prevents injury. Misidentification and persecution: Slow worms are sometimes killed by people who mistake them for snakes. Education is the primary prevention. Cats: Cat predation is a significant mortality cause, particularly for juveniles. Development: Building and landscaping operations destroy slow worm habitat and populations. Planning surveys are required where slow worms are present.
Installing artificial refugiaāpieces of corrugated roofing iron, old carpet squares, or purpose-made reptile hibernaculaāin sunny garden spots creates habitat that supports slow worm populations. Maintaining compost heaps, leaving log piles, and avoiding total grass cutting all support slow worms.
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