Skip to main content

Effects of diet and temperature on monarch butterfly wing morphology and flight ability

Abstract

Background

While global change research has greatly expanded in recent years, it remains unclear how environmental change will impact the mobility of many organisms. Flight is an important mode of transportation that affects ecological functions, including mate location, foraging, and migration. However, the effects of increasing temperature and diet quality on flight remain largely unknown. Here, we explore the effects of rearing temperature and larval diet quality on the flight ability of an iconic and ecologically threatened migratory insect, the monarch butterfly, Danaus plexippus.

Experimental Design

Monarch larvae were reared at two temperatures (25 °C and 28 °C) and on three milkweed species with varying phytochemistry (Asclepias incarnata, Asclepias syriaca, and Asclepias curassavica) in a fully factorial experiment. We tested flight ability using an automated flight mill, which measured cumulative flight distance, duration, and instantaneous velocity.

Results

Higher rearing temperatures reduced monarch flight ability, and larval diet quality influenced forewing morphology. Dietary milkweed with higher cardenolide concentrations (A. curassavica) induced shorter, wider forewings whereas milkweed with low to intermediate cardenolides (A. incarnata and A. syriaca) induced longer, narrower forewings, which are considered better for gliding flight used during migration.

Implications for Insect Conservation

Our results provide evidence that projected increases in temperature and the subsequent expansion of tropical milkweed (A. curassavica) into the central breeding range of eastern North American migratory monarchs could reduce migration success. Further research is needed to identify mechanisms explaining the effects of diet and temperature on monarch flight ability and fitness, to ensure that appropriate conservation strategies are employed to preserve migratory populations.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Data Availability

Data will be made available in a Dryad Digital Repository upon acceptance of the manuscript.

References

Download references

Acknowledgements

Many thanks to H. B. Streit, A. R. Meier, J. Kristofik, K. Moriarty, T. McClanaghan, and K. Markiewicz for their lab and field assistance in the completion of this project. Thanks also to M. Palmer and P. Girard for their aid with milkweed propagation in the greenhouses at the University of Michigan Matthaei Botanical Gardens. This work was completed in the research facilities of the University of Michigan and was funded by National Science Foundation Grant DEB-1256115 awarded to M. D. Hunter.

Author information

Authors and Affiliations

Authors

Contributions

AJS and MDH designed the experiment; LED provided butterflies and expertise during larval development and flight trials; AJS collected the data and analyzed it with MDH; AJS wrote the manuscript; all authors contributed to drafts.

Corresponding author

Correspondence to Abrianna J. Soule.

Ethics declarations

Conflict of interest

The authors declare they have no conflict of interest.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 18 kb)

Supplementary file2 (XLSX 182 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Soule, A.J., Decker, L.E. & Hunter, M.D. Effects of diet and temperature on monarch butterfly wing morphology and flight ability. J Insect Conserv 24, 961–975 (2020). https://doi.org/10.1007/s10841-020-00267-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10841-020-00267-7

Keywords

  • Danaus plexippus
  • Environmental change
  • Migration
  • Flight ability
  • Plant secondary metabolites
  • Conservation