Bombus hortorum also known as the garden bumblebee displays a wide range of colour forms.
A bumblebee is any one of over 250 species in the Bombus genus, whose name derives from the Latin for a buzzing or humming sound. We have been digitising the Museum’s collection of British Bumblebees in order to release a new resource to those researching and working with Bees globally. There are 24 species of Bumblebees in Britain, but only around eight are widespread and abundant throughout the UK. Bumblebees have round bodies covered in soft hair called pile. This makes them appear fuzzy or furry. Within species there can be a range of differing colour forms. Some bees also produce melanic individuals which have much larger quantities of melanin than normal, and so look much darker. Queens, males and worker bees all vary too, which can make species identification quite difficult. Having an openly accessible resource online, to check specimens against in the field would be useful to researchers and anyone else interested in bees.
We have recently finished imaging more than 6,700 specimens from all over the UK and Ireland, from Scilly to Shetland. The collection’s oldest specimens date back to the 19th century, while the most recent additions are from 2017. This is part of a NERC funded research grant with principle investigators Richard Gill from Imperial College, London and Ian Barnes from the Museum. These specimens are currently being used in this research by Scientists at the Museum and Imperial College London, but will be released to the Data Portal for wider use when research is complete.
Having a record from the 19th Century until present day, of which species were seen, at which time in the year, and at what location is extremely important. Natural history collections are the only accurate records of specimens dating back over 200 years. By adding natural history collection data to modern observational data, scientists can get a much better picture of how biodiversity of an area reacts to environmental changes over time.
Older specimens can tell us about bumblebee distribution before climate change and other changes e.g. in land use, while more recent specimens can show the impact of changes. Change in biodiversity doesn’t always reduce populations. Bombus hypnorum, the tree bumblebee, is common through the European continent and Asia. It was first found in England in 2001, and has rapidly spread to the UK, moving north as far as Scotland. The collection includes some of the first tree bumblebee specimens found in London – discovered in the Museum’s Wildlife Garden in 2006. This species nests in tree holes and bird boxes so exploiting habitats that other species do not.
Bees are important pollinators that look after some key crops. While moving between flowers they carry pollen, enabling plants to produce fruits, nuts and vegetables. Pollinating wild plants allows them to cross breed and stay genetically healthy, supporting diverse and flourishing ecosystems. It is estimated that one third of the food we each day relies on pollinators; either pollinating the vegetables and fruits we eat directly, or pollinating the food for the animals that we then consume.
Dr Adriana De Palma is a researcher on the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project. Adriana investigates how biodiversity responds to human pressures such as land-use change, pollution, invasive species and infrastructure.
“Bumblebees are a really interesting group, because they can actually respond very differently to human impacts than many other bees. They are particularly large, so can fly quite a long way from their nests to find food. This can help them take advantage of some of the changes humans have made to the landscape, like the glut of resources provided by oilseed rape and other mass-flowering crops. But they can also be much more sensitive to some changes than other species. For example, our data from species in North America shows that there are far fewer individuals and types of bumblebees in secondary vegetation (areas that have been previously cleared by people, but then left to regrow into more natural systems) than there are in land that has never been cleared. Understanding how human behaviour can help or hinder bee populations can help us plan for a future in which both humans and bees thrive.” Dr Adriana De Palma
To digitise the bees our digitiser, Phaedra Kokkini, used the pinned insect workflow previously used to digitise our Madagascan moths and butterflies, with minor changes. The majority of the bees in this collection are smaller than specimens in previous workflows, so we were able to move the specimen tray closer to the camera to capture the optimal image of the specimen and labels. After the imaging, Phaedra transcribed key information from the labels, such as the collection date and species, then georeferenced the collection location.
“I felt that the bumblebees were much easier to image than previous pinned insect projects because the collection was very nicely curated, in new drawers, and the specimens were in very good condition and therefore not as fragile as others I have worked on.”
Specimen size also varied less than in previous projects, allowing us to get through more specimens each day as the focus didn’t need to be adjusted between the images of the same species. On average we imaged 220 Bombus specimens each day.
“The bumblebee project was like exploring the UK while travelling back in time. While doing the transcription and georeferencing I had to research and find locations that many people haven’t heard of and that might not even exist anymore. I had to find references for places that had changed name or county, or were merged with big cities. I had to decode abbreviations, strange handwriting and different (or wrong) spellings. You can really see how the country has changed over time through the data on the labels.” Phaedra Kokkini
Standards of recording information have also changed over time. The older specimens might have a very general location recorded and nothing else, while new ones usually have specific coordinates or a grid reference, which can be exactly pinpointed. Find out what detective work can go into putting Geography into our collections in a previous blog.
Besides the specific aims of the current project, digitisation releases data which can be fed into species recording schemes such as BWARS (Bees, Wasps & Ants Recording Society). Also it supports any project where data needs to be linked to specific specimens, since all specimens now have unique reference numbers and records on the Museum database where associated data can be stored.