Press release 2010/07
Issued by the Centre for Ecology & Hydrology
26 June 2010
Scientists seek help as native parasites attack ladybird invader
New Ladybird Parasite Survey offers chance to witness evolution in action
Scientists investigating the spread of the invasive harlequin ladybird are asking the public to help record examples of native parasites attacking the alien species.
They hope to understand how parasitic flies and wasps, known to attack the UK’s native ladybirds, are now interacting with the alien harlequin ladybird. Little is known about ladybird parasites in general and the new Ladybird Parasite Survey provides a wonderful opportunity to witness evolution in action.
The research team, from the Centre for Ecology & Hydrology and the University of Cambridge, jointly run the long-running UK Ladybird Survey. This summer they have joined with schools involved in the BBC Breathing Places project to highlight the new Ladybird Parasite Survey.
Tiny native parasitic flies and wasps commonly lay their eggs in native ladybirds, subsequently causing death to the host. Over the last twelve months evidence has emerged that alien harlequin ladybirds, first spotted in the UK in 2004, are also being attacked by parasitic flies and wasps. The parasitic insects seem to be adapting to life with the harlequin ladybird. However several key questions remain. In particular scientists need to know whether the parasite attacks the alien harlequin at a similar rate to the native ladybird and whether this is changing over time.
Members of the public joining the Ladybird Parasite Survey must first find some ladybird pupae, usually found fixed to the leaves of broad-leaved trees, conifers and low-growing plants, then take samples home in containers with a clear lid (for example cling film over a yoghurt pot), and finally check the pupae every day to see what is happening.
Now is the prime time to find ladybird pupae and hence parasites. Parasitic flies and wasps have been encountered in all developmental stages of ladybirds, but larvae and pupae are attacked more often than eggs and adults.
An adult ladybird will usually emerge from a pupa within one to two weeks. If the pupa has been attacked by a parasite, then this will emerge instead of a ladybird.
Once the ladybird or parasites have emerged people can record the results, including photographs, of their experiment on the BBC Breathing Places Ladybird Parasite Survey website. The results will contribute valuable data to the UK Ladybird Survey.
Dr Helen Roy, UK Ladybird Survey co-ordinator from the Centre for Ecology & Hydrology, said, “We will be able to witness evolution in action as the native parasites begin to adapt to life within the alien harlequin. Coupling the successful UK Ladybird Survey with the Ladybird Parasite Survey provides an exciting opportunity to explore links between species within a complex food web.”
There’s still time to get involved with the project. To take part, all schools have to do is register at www.bbc.co.uk/breathingplaces/schools Registered schools will automatically receive teaching notes and other activity sheets are available on the website.
Ladybird and parasite facts
There are 47 different species of ladybird resident in Britain, which play a key role in our ecosystem. Many ladybirds are voracious predators of crop and garden pest insects, particularly aphids.
A number of species feed on ladybirds and are referred to as “natural enemies”. Many species of ladybird contain a variety of bitter tasting, toxic chemicals and this, coupled with their bright ‘warning’ colours (aposematism), deters many potential natural enemies. However, the few natural enemies, mainly parasites, that overcome the defences of ladybirds are diverse.
There are three main parasitic insects of ladybirds; phorid flies (maggots which rapidly become small brown cocoons around 3mm long), chalcid wasps (up to 2mm long), or a braconid wasp (emerges as a single large yellow maggot around 10mm long that rapidly spins a cocoon).
Phorids are currently thought to be the most common of these but the research team hopes enough people will contribute to the Ladybird Parasite Survey to allow them to look in more detail at the numbers of different parasites across the country.
The UK Ladybird Survey (http://www.ladybird-survey.org/) has been running since the 1960s but ladybirds have been recorded in the UK for several centuries.
In recent years a new ladybird arrival has been spotted in the UK. The Harlequin ladybird was introduced to North America in 1988, where it is now the most widespread ladybird species on the continent. It has already invaded much of north-western Europe, and arrived in Britain in summer 2004.
The harlequin can eat more than 12000 aphids in a year. Unfortunately, harlequins prey on more than just pest insects, and will eat non-pest and beneficial insects, including the larvae of other ladybirds.
Notes to Editors
Further information for journalists can be obtained from the CEH press office.
To contact a Ladybird scientist:
Dr Helen Roy, Centre for Ecology & Hydrology, Mobile: 07540 167488, email: hele@ceh.ac.uk
Dr Remy Ware, University of Cambridge, Mobile: 07763 613196 email: rlw29@cam.ac.uk
Photographs: Five images will accompany this release in a second email. Contact Barnaby Smith at the Centre for Ecology & Hydrology (mobile: 07920 295384, email: bpgs@ceh.ac.uk) for details of other suitable images.
Further information on BBC Breathing Places: Grace Comely, Tel: 0208 008 5022
Additional notes:
BBC Breathing Places is a five-year BBC Learning Campaign to inspire people to connect with nature. Developed in partnership with a huge range of wildlife and conservation organisations, the campaign encourages new audiences to get involved in doing one thing for nature. As well as environmental organisations, Breathing Places also works in partnership with other volunteer associations, city councils and education groups, visit: www.bbc.co.uk/breathingplaces.
Members of the BBC Breathing Places Schools UK partnership include government agencies, charitable organisations, volunteer groups and educational projects. A full list of partners can be found at bbc.co.uk/breathingplaces/partners.
Visit the International Year of Biodiversity website: http://www.biodiversityislife.net/
The UK Ladybird Survey is run by scientists from the Centre for Ecology & Hydrology, the University of Cambridge and Anglia Ruskin University. http://www.ladybird-survey.org/
The Centre for Ecology & Hydrology (CEH) is the UK's Centre of Excellence for integrated research in the land and freshwater ecosystems and their interaction with the atmosphere. CEH is part of the Natural Environment Research Council, employs more than 450 people at five major sites in England, Scotland and Wales, hosts over 150 PhD students, and has an overall budget of about £35m. CEH tackles complex environmental challenges to deliver practicable solutions so that future generations can benefit from a rich and healthy environment. www.ceh.ac.uk
The Natural Environment Research Council (NERC) funds world-class science, in universities and its own research centres, that increases knowledge and understanding of the natural world. It is tackling major environmental issues such as climate change, biodiversity and natural hazards. NERC receives around £400m a year from the UK government's science budget, which is used to provide independent research and training in the environmental sciences. www.nerc.ac.uk
