Results – Three Years of the Big Wasp Survey

It’s been a fabulous three years of Big Wasp Survey! Here’s an update of what we’ve achieved, what we’re doing with the data and where we’re going next. Huge thanks all our participants and sponsors, for making this project such a success! We hope you find these results interesting and informative, and we look forward to your continued support.

Big Wasp Survey Summary Report 2019_final


Why We Need the Big Wasp Survey

The Big Wasp Survey is a citizen science project that was set up in the UK in 2017 by Prof Adam Hart (University of Gloucestershire) and Dr Seirian Sumner (UCL). The aim was to engage the public in a project that tackled the negative attitudes people have towards wasps and improved our
understanding of wasp biology, diversity and distributions across the UK. Although we had big ambitions for the Big Wasp Survey we weren’t really sure how it would all pan out. But the enthusiasm of so many citizen scientists and the spread of #wasplove across the late summer meant
our ambitions were exceeded!

Unlike honeybees, social wasps are little studied, and the important ecosystem services they provide – as natural predators that regulate populations of other insects and arthropods – is largely unappreciated. The Big Wasp Survey asked members of the public to make a simple wasp trap, hang it in their garden for seven days, and then send in the trap contents to the scientists in order that the wasps could be identified.

Why Killing the Wasps is Necessary and Ok

Wasps are difficult to identify to species level without killing them; it takes a good hand-lens or microscope and a trained eye to distinguish even the nine species we find in the UK. However, the Big Wasp Survey is designed to minimise impact on wasp populations: it is timed so that it attracts
only workers – indeed, we have not found a single queen among the thousands of wasps that have now been processed. The traps do not attract males. You can read more about the issues around lethal sampling of insects here and here, or listen to Prof Hart’s Radio 4 programme here

Big Wasp Survey Generates High Quality Data on Wasp Distributions

Thanks to everyone’s help, and to some serious wasp sorting over the winter, we were able to publish the first BWS scientific paper in the journal Insect Conservation and Diversity. The main findings are summarised below (apologies – we couldn’t afford the open access fees for the journal).

The 2017 survey ran from 26th August to 10th Sept; 2377 people registered to take part, and 54.4% (1294) of these people submitted their results. Of these, 551 traps (42.5%) contained wasps, representing 548 postcodes across the UK; 6680 wasps could be identified to species level; a further 180 wasps from 39 traps were too damaged to identify.

Three species dominated: the common yellowjacket wasp Vespula vulgaris accounted for 44% of wasps (2942 wasps in 407 traps); the German yellowjacket wasp Vespula germanica accounted for a further 44%. (2974 wasps in 251 traps); and the European hornet Vespa crabro accounted for 6% of the sample (395 wasps in 100 traps) (see Fig 1). We also detected small number of Vespula rufa (2 in 2 traps) and Dolichovespula media (9 wasps in 6 traps).

By comparing with a long-term dataset of the same species collected by members of the Bees, Wasps and Ants Recording Scheme (BWARS), we were able to show that the quality of the data being generated by the Big Wasp Survey is excellent. It is less spatially biased than BWARS data
(meaning that Big Wasp Survey is sampling wasps more evenly across the UK), and the species distribution maps obtained from just two weeks Big Wasp Survey sampling generated similar maps to the long-term dataset, suggesting that our data make biological sense.