When park ranger Dale Osborne noticed that torrential rain was constantly flooding the plains of Watermead Country Park North in Leicestershire, England, he watched helplessly as local harvest mice lost their nests and found himself picking up mice swimming around in the water to place them on dry land. In 2013, Osborne and his colleague implemented a conservation tactic that had been slowly circulating throughout Britain for years, cutting small openings in used tennis balls and propping them up on raised stakes throughout the park to create safe elevated nests for the displaced rodents. The innovative solution proved remarkably effective, as harvest mice are so small that roughly 10 individuals could fit inside a single tennis ball, and the raised rubber-core homes provided crucial protection from prowling predators and birds of prey while giving the local population a much-needed boost despite the constant flooding. That first summer, Osborne and his team received 550 donated tennis balls from the public to help rehome the tiny harvest mice, establishing a grassroots conservation program that has continued growing stronger over the past decade.
The initiative now receives significant support from the iconic Wimbledon Championships, which cycles through over 50,000 tennis balls annually and donates many of them to conservation causes, effectively diverting waste from landfills while simultaneously providing critical habitat for vulnerable mouse populations. The tennis ball mouse houses have proven so successful at addressing habitat loss that harvest mice populations in areas using the program remain stable, showcasing how creative repurposing of everyday items can solve real conservation challenges while keeping important species thriving in their ecosystems.
