Researchers have found that moths and hover flies are more negatively affected by urbanisation than bees, prompting calls for gardeners to work with neighbours to support these less glamorous but vital pollinators.
A study from the University of Sheffield's school of biosciences investigated the impact of urbanisation on pollinators in the UK. It found that urban landscapes support 43% fewer pollinator species, with the biggest declines occurring deeper in city centres. For every 10% increase in impervious surfaces such as roads and buildings, there was a reduction of up to 7.5% in the variety of pollinating species.
Lead author Emilie Ellis, who conducted the research as part of her PhD, said: 'The original focus was going to be on bees as they’re the most charismatic species. But then my interest in moths added this on to it, and then [co-author Stuart Campbell]’s interest in flies included hover flies.' The study, published in the Royal Society's Proceedings B, involved sampling insects at allotments in Leeds, Leicester and Sheffield over the summer of 2019.
Ellis hypothesised that moths and hover flies are more vulnerable because they have more complex life cycles, requiring different resources beyond flowers. She suggested that gardeners and urban planners can help by providing diverse habitats, including shrubs, ponds, trees, and untouched grass patches. 'The diversity of habitat is the most important,' she said.
Ellis emphasised the importance of collaboration: 'A huge thing that’s important is collaborating and talking to your neighbours and families and friends and encouraging them to do it too. Because an individual allotment or flower garden is pretty small and almost useless, but when you create a whole network of people that are interested and engaged these small little patches can become these huge habitat networks in cities.'
