Migrating moths and songbirds travel at similar rates
9 March 2011
A study published today (09 March) in Proceedings of the Royal Society B by researchers at Rothamsted Research (an institute of the Biotechnology and Biological Sciences Research Council), and the universities of Lund (Sweden), Greenwich and York, reports the surprising finding that night-flying moths are able to match their songbird counterparts for travel speed and direction during their annual migrations but they use quite different strategies to do so - information that adds to our understanding of the lifestyle of such insects, which are important for maintaining biodiversity and food security.
This new international study of moth migration over the UK, and songbird migration over Sweden, funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Swedish Research Council, shows that songbirds (mainly Willow Warblers) and moths (Silver Y moths) have very similar migration speeds - between 30 km and 65 km per hour - and both travel approximately northwards in the spring and southwards in the autumn.
Dr Jason Chapman, Rothamsted Research, one of the lead authors on the paper said "Songbirds such as warblers and thrushes are able to fly unassisted about four times faster than migratory moths, which might appear to be largely at the mercy of the winds. So we had assumed that songbirds would travel much faster over the same distance. It was a great surprise when we found out the degree of overlap between the travel speeds - the mean values are almost identical, which is really remarkable."
The discovery gives fresh insight into exactly how moths are able to travel in their billions from summer breeding grounds in the UK and elsewhere in northern Europe to their winter quarters in the Mediterranean region and sub-Saharan Africa, thousands of kilometres away. This is important information in the context of declining moth populations and a critical need for pollinating insects to ensure maximum yields of food crops in the face of a potential food security crisis - the more we understand about the lifecycle and lifestyle of these insects, the better we can understand and mitigate the challenges they face for survival.
The team used specially-designed radars to track the travel speeds and directions of many thousands of individual Silver Y moths and songbirds on their night-time spring and autumn migrations.
The similarity in speed results from contrasting strategies: moths fly only when tailwinds are favourable, so gaining the maximum degree of wind assistance; whereas birds fly on winds from a variety of directions, and consequently receive less assistance. Our findings therefore demonstrate that moths and songbirds have evolved very different behavioural solutions to the challenge of moving great distances in a seasonally-beneficial direction in a short period of time.
Professor Jane Hill, who led the team at the University of York, said: "We know that many animals migrate north in spring to take advantage of summer breeding conditions in northern Europe, before returning south in winter. Given the huge differences in size and flight ability between moths and birds, we were surprised that by taking advantage of suitable winds, moths can travel so quickly.
"Migrant insects are tending to become more abundant in northern Europe, whereas many species of migrant songbirds are undergoing serious declines. These contrasting fortunes might be partly explained by the highly efficient migration strategies employed by insects that we demonstrate in this new study."
Professor Douglas Kell, Chief Executive, BBSRC said "Insects play a number of very important roles, including the pollination of food crops and other plants. They can also be a problem, causing damage to plants that can lead to yield losses. The more we can understand about insects - how they live, reproduce, find food, become prey for other animals, and more - the better we can tackle some of the problems they both cause and alleviate."
Notes for editors
The research is published in the current issue of Proceedings of the Royal Society B (published 9 March 2011) as "Convergent Patterns of Long-distance Nocturnal Migration in Noctuid Moths and Passerine Birds" by Thomas Alerstam, Jason W. Chapman, Johan Bäckman, Alan D. Smith, Håkan Karlsson, Cecilia Nilsson, Don R. Reynolds, Raymond H. G. Klaassen, and Jane K. Hill. The study was funded by the UK Biotechnology and Biological Sciences Research Council (BBSRC) and the Swedish Research Council.
About Rothamsted Research
Rothamsted Research is centred in Harpenden Hertfordshire and is the largest agricultural research institute in the country. The mission of Rothamsted Research is to be recognised internationally as a primary source of first-class scientific research and new knowledge that addresses stakeholder requirements for innovative policies, products and practices to enhance the economic, environmental and societal value of agricultural land. The Applied Crop Science department is based at Broom's Barn, Higham, Bury St. Edmunds. North Wyke Research is located near Okehampton in Devon. www.rothamsted.ac.uk
For further information, please contact the Rothamsted Research Press Office (see external contacts below).
About The Migration Ecology Group at Lund University
The Migration Ecology Group at Lund University, Sweden, is one of the world's leading institutes in the study of bird migration. This might not be a coincidence as Lund is situated only a stone's throw from the Falsterbo Peninsula, one of Europe's bird migratory hotspots. Bird migration is studied using molecular biology methods, experimental studies in the wind tunnel, together with field studies with video techniques, radar and satellite transmitters, but also mathematical modelling. By a multi-disciplinary approach we aim to understand the adaptive values and evolutionary possibilities and limitations in animal migration, flight, orientation and energetics. www.zoo.ekol.lu.se/index_en.htm
About The University of York's Department of Biology
The University of York's Department of Biology is one of the leading centres for biological teaching and research in the UK. In the 2008 Research Assessment Exercise, it was ranked equal first among broad spectrum bioscience departments in the UK for quality that was judged to be world-leading. The Department both teaches degree courses and undertakes research across the whole spectrum of modern Biology, from molecular genetics and biochemistry to ecology.
For more information contact Professor Jane Hill (see external contacts below).
BBSRC is the UK funding agency for research in the life sciences. Sponsored by Government, BBSRC annually invests around £470M in a wide range of research that makes a significant contribution to the quality of life in the UK and beyond and supports a number of important industrial stakeholders, including the agriculture, food, chemical, healthcare and pharmaceutical sectors.
BBSRC provides institute strategic research grants to the following:
- The Babraham Institute
- Institute for Animal Health
- Institute of Biological, Environmental and Rural Sciences (Aberystwyth University)
- Institute of Food Research
- John Innes Centre
- The Genome Analysis Centre
- The Roslin Institute (University of Edinburgh)
- Rothamsted Research
The Institutes conduct long-term, mission-oriented research using specialist facilities. They have strong interactions with industry, Government departments and other end-users of their research.
Dr Jason Chapman, Rothamsted Research, UK
tel: 01582 763133 ext 2431
Professor Thomas Alerstam, Lund University, Sweden
tel: +46 46 2223785
Dr Adélia de Paula, Rothamsted Research Press Office
tel: 01582 763133 ext 2260
Professor Jane Hill, The University of York
tel: 01904 328642