Brown Drake Mayfly
May flies are
sensitive to pollution of many types including heavy metals. Exposure to the zinc can have larger effects on the adults and subimagos than the larvae.
Wesner and Colleagues* reared mayflies
(Centroptilum triangulifer) in water with increasing concentrations of zinc from 32 to 476 ppb (parts zinc per billion parts water). Adult mortality steadily increased from 32 to 476 ppb zinc. Larva mortality decreased very slowly with concentration until concentrations reached about 200 ppb, then declined more rapidly.
Why are the adults more sensitive? Zinc concentrations above 139 ppb visibly affect wing pad development. Lower zinc concentrations may affect development in ways that are not visible or interfere with other structures. Deformed wing pads or other deformities can interfere with metamorphosis, a sensitive period with elevated mortality in mayflies. One of the ways that zinc may reduce mayfly populations is affects on successful molting.
J. S. Wesner, J. M. Kraus, T. S. Schmidt, D. M. Walters, and W. H. Clements. 2014. Metamorphosis Enhances the Effects of Metal Exposure on the Mayfly, Centroptilum triangulifer. Environmental Science & Technology.
DOI: 10.1021/es501914y
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About jjneal
Jonathan Neal is a retired Associate Professor of Entomology at Purdue University and author of the textbook, Living With Insects (2010).
This blog is a forum to communicate about the intersection of insects with people and policy. This is a personal blog.
The opinions and materials posted here are those of the author and are in no way connected with those of my employer.
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