Thank you to everyone who submitted surveys in 2017 and 2018. We received records from 599 participants, from as far north as the Shetland Islands and as far south as the Isles of Scilly.
In this blog post, we share with you some of the initial findings which we are currently developing into journal papers, and our new results video.
The bumblebees
In 2017, a total of 4,200 bumblebees were recorded by participants. We were able to verify over 3,000 of these records to species level using the photographs provided. You can find out more about the verification process and recorder accuracy in our blog post about bumblebee ID.
A total of 15 bumblebee species were confirmed during surveying, suggesting that gardens can be valuable habitats for a wide range of species, including some scarce species.
The three most recorded bumblebee species were the Buff-tailed Bumblebee (38%), followed by the Common Carder Bee (25%), and the Red-tailed Bumblebee (11%). We also received two records of the less common Heath Bumblebee and two records of the Bilberry Bumblebee, which were noteworthy as these species tend to be strongly associated with semi-natural habitats. The rarest species recorded were the Ruderal Bumblebee and the Moss Carder Bee. These two species are both conservation priorities, listed under section 41 of the UK post-2010 Biodiversity Framework.
Gardens located in urban areas reported significantly more bumblebees than those in rural areas, reinforcing the important role that gardens can play in supporting urban bumblebee populations.
The flowers
To explore which flowers were most visited by bumblebees we used the data from the 1,657 complete surveys we received in 2017. A total of 238 different plant species were surveyed.
We grouped plants by genus for analysis which revealed that the top three most visited plants were Viper’s-bugloss (Echium species), Teasel (Dipsacus species) and Toadflax (Linaria species). Together, these three plants offer forage from late May to early autumn and are in flower when bumblebee activity is at its peak.
Around half of the surveys we received were of the Mignon series Dahlia’s we trialled. You can read about the results from the dahlia trial on our website.
If you’d like to support bumblebees in your garden, aim to grow as many flowers as you can. Include a variety of shapes, colours and flowering times in order to appeal to different species of bee. For more tips on providing bumblebee habitat and forage visit the gardening pages of our website.
Visit the RHS website and download the Plants for Pollinator lists for guidance on insect-friendly garden plants, wildflowers and exotics.