Journal of Insect Conservation

, Volume 19, Issue 5, pp 1029–1035 | Cite as

Road mortality potentially responsible for billions of pollinating insect deaths annually

  • James H. Baxter-Gilbert
  • Julia L. Riley
  • Christopher J. H. Neufeld
  • Jacqueline D. Litzgus
  • David LesbarrèresEmail author


Pollinating insects are vital to the survival of many primary producers in terrestrial ecosystems, as up to 80–85 % of the world’s flowering plants require pollinators for reproduction. Over the last few decades however, numerous pollinating insect populations have declined substantially. The causes of these declines are multifaceted and synergistic, and include pesticides, herbicides, monoculture, urbanization, disease, parasites, and climate change. Here, we present evidence for a generally understudied yet potentially significant source of pollinator mortality, collisions with vehicles. Negative impacts from roads have been observed for the majority of vertebrate groups but studies of the effects on invertebrates have remained largely absent from the scientific literature. We documented road mortality of pollinating insects along a 2 km stretch of highway in Ontario, Canada and used our findings to extrapolate expected levels of road mortality across a number of landscape scales. Our extrapolations demonstrate the potential for loss of hundreds of thousands (on our studied highway) to hundreds of billions (generalised across North America) of Lepidopterans, Hymenopterans and pollinating Dipterans each summer. Our projections of such high levels of annual road mortality highlight the need for research to assess whether the mortality levels observed are contributing to the substantial declines of pollinating insects occurring on a global scale, thus putting the ecological functioning of natural areas and agricultural productivity in jeopardy.


Biodiversity Diptera Hymenoptera Lepidoptera Pollinator declines Road ecology 



The authors thank J.E. Baxter-Gilbert, S. Boyle, G. Hughes, D. Jones, R. Maleau, L. Monck-Whipp, and K. Tabobondung and many volunteers for their field assistance, C. Beckett-Brown, B. Hewitt, K. Marchand, M. McGee, J. Montgomery, R. Morin, B. Squirrell, and J. Woolley for their laboratory assistance. We would also like to thank the two anonymous reviewers for their insights and suggestions during the preparation of this article. Financial support for this research was provided by Magnetawan First Nation, Laurentian University, the Ontario Ministry of Natural Resources, and the Ministry of Transportation Ontario (MTO). All research was authorized by Magnetawan First Nation’s Chief and Council. Opinions expressed in this paper are those of the authors and may not necessarily reflect the views and policies of the MTO.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • James H. Baxter-Gilbert
    • 1
    • 2
  • Julia L. Riley
    • 1
    • 2
  • Christopher J. H. Neufeld
    • 1
  • Jacqueline D. Litzgus
    • 1
  • David Lesbarrères
    • 1
    Email author
  1. 1.Department of BiologyLaurentian UniversitySudburyCanada
  2. 2.Division of Brain, Behaviour and Evolution, Department of Biological SciencesMacquarie UniversityMarsfieldAustralia

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