Journal article

Caddisfly egg mass morphology mediates egg predation: potential costs to individuals and populations

William D Bovill, Barbara J Downes, Jill Lancaster



Egg predation is seldom considered in life-history studies of freshwater insects, but could be an important source of mortality with potential to limit population numbers. Costs of egg predation to prey can be considered at two levels: (i) fitness costs to individuals via reduced reproductive output; and (ii) population costs via reduced recruitment of benthic larvae. Larvae of Orthotrichia armata (Trichoptera: Hydroptilidae) feed on the egg masses of caddisflies in the Little River, central Victoria, Australia, but the small size of O. armata suggests that they may be unable to penetrate egg masses that are covered with a thick layer of spumaline jelly. We predicted that predation by O. arm..

View full abstract


Funding Acknowledgements

This study was funded by an Australian Postgraduate Award (scholarship) and grants from the Holsworth Wildlife Research Endowment awarded to W. Bovill. Special thanks to Alice Wells for assisting with the identification of Orthotrichia armata. We also thank Beatrice Bovill for field assistance, and Dylan and Julia White for field accommodation. Research in Cathedral Range State Park was conducted with a permit from the Department of Sustainability and Environment, State Government of Victoria.