Proceedings of the Royal Society B: Biological Sciences
Restricted accessResearch articles

Convergent patterns of long-distance nocturnal migration in noctuid moths and passerine birds

Thomas Alerstam

Thomas Alerstam

Department of Biology, Animal Ecology, Lund University, Ecology Building, 22362 Lund, Sweden

[email protected] [email protected]

Google Scholar

Find this author on PubMed

,
Jason W. Chapman

Jason W. Chapman

Plant and Invertebrate Ecology Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK

[email protected] [email protected]

Google Scholar

Find this author on PubMed

,
Johan Bäckman

Johan Bäckman

Department of Biology, Animal Ecology, Lund University, Ecology Building, 22362 Lund, Sweden

Google Scholar

Find this author on PubMed

,
Alan D. Smith

Alan D. Smith

Plant and Invertebrate Ecology Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK

Google Scholar

Find this author on PubMed

,
Håkan Karlsson

Håkan Karlsson

Department of Biology, Animal Ecology, Lund University, Ecology Building, 22362 Lund, Sweden

Google Scholar

Find this author on PubMed

,
Cecilia Nilsson

Cecilia Nilsson

Department of Biology, Animal Ecology, Lund University, Ecology Building, 22362 Lund, Sweden

Google Scholar

Find this author on PubMed

,
Don R. Reynolds

Don R. Reynolds

Plant and Invertebrate Ecology Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK

Natural Resources Institute, University of Greenwich, Chatham, Kent ME4 4TB, UK

Google Scholar

Find this author on PubMed

,
Raymond H. G. Klaassen

Raymond H. G. Klaassen

Department of Biology, Animal Ecology, Lund University, Ecology Building, 22362 Lund, Sweden

Google Scholar

Find this author on PubMed

and
Jane K. Hill

Jane K. Hill

Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK

Google Scholar

Find this author on PubMed

    Vast numbers of insects and passerines achieve long-distance migrations between summer and winter locations by undertaking high-altitude nocturnal flights. Insects such as noctuid moths fly relatively slowly in relation to the surrounding air, with airspeeds approximately one-third of that of passerines. Thus, it has been widely assumed that windborne insect migrants will have comparatively little control over their migration speed and direction compared with migrant birds. We used radar to carry out the first comparative analyses of the flight behaviour and migratory strategies of insects and birds under nearly equivalent natural conditions. Contrary to expectations, noctuid moths attained almost identical ground speeds and travel directions compared with passerines, despite their very different flight powers and sensory capacities. Moths achieved fast travel speeds in seasonally appropriate migration directions by exploiting favourably directed winds and selecting flight altitudes that coincided with the fastest air streams. By contrast, passerines were less selective of wind conditions, relying on self-powered flight in their seasonally preferred direction, often with little or no tailwind assistance. Our results demonstrate that noctuid moths and passerines show contrasting risk-prone and risk-averse migratory strategies in relation to wind. Comparative studies of the flight behaviours of distantly related taxa are critically important for understanding the evolution of animal migration strategies.

    References