Hostname: page-component-7c8c6479df-8mjnm Total loading time: 0 Render date: 2024-03-28T09:04:51.380Z Has data issue: false hasContentIssue false

REACTIONS OF THE LARVAE OF THREE RHEOPHILIC SPECIES OF TRICHOPTERA TO SELECTED INSECTICIDES1

Published online by Cambridge University Press:  31 May 2012

F. J. H. Fredeen
Affiliation:
Research Station, Canada Department of Agriculture, Saskatoon, Saskatchewan

Abstract

Procedures are outlined for evaluating in aquaria the effects of insecticides against rheophilic species of Trichoptera larvae (Brachycentrus lateralis (Say), Hydropsyche morosa Hagen, and H. recurvata Banks). In general DDT, DDD, and methoxychlor were considerably more toxic than were malathion, Baytex®, or diazinon and their regression lines were steeper. Some of the methoxychlortreated larvae recovered within 18 hours after treatment but the reverse was true for DDT, DDD, and the organophosphates. DDT dissolved in ethanol was considerably more toxic than any of the three commercial formulations of DDT tested. Sensitivity to DDT declined (i.e.LC50 values were higher) with increasing size (age) of the larvae. LC50 values of DDT also varied directly with the densities of tested populations in tests containing more than 10 larvae per 250 ml of water. Toxicities of all chlorinated hydrocarbons varied indirectly with the temperature and those of the organophosphates directly. The significance of these findings to laboratory and field tests is discussed.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1972

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bowman, M. C., Acree, F. Jr., Schmidt, C. H., and Beroza, M.. 1959. Fate of DDT in larvicide suspensions. J. econ. Ent. 52: 10381042.CrossRefGoogle Scholar
Carlson, C. A. 1966. Effects of three organophosphorus insecticides on immature Hexagenia and Hydropsyche of the upper Mississippi River. Trans. am. Fish. Soc. 95: 15.CrossRefGoogle Scholar
Corbet, P. S., Schmid, F., and Augustin, C. L.. 1966. The Trichoptera of St. Helen's Island, Montreal. I. The species present and their relative abundance at light. Can. Ent. 98: 12841298.CrossRefGoogle Scholar
Fredeen, F. J. H. 1969. A new procedure allowing replicated miniature larvicide tests in a large river. Can. Ent. 101: 713725.CrossRefGoogle Scholar
Fredeen, F. J. H. 1972. The temporary abatement of nuisance species of Trichoptera with DDD (TDE) larvicide. Can. Ent. 104: 145163.CrossRefGoogle Scholar
Jamnback, H. 1962. An eclectic method of testing the effectiveness of chemicals in killing blackfly larvae (Simuliidae: Diptera). Mosquito News 22: 384389.Google Scholar
Jensen, L. D. and Gaufin, A. R.. 1964. Effects of ten organic insecticides on two species of stonefly naiads. Trans. am. Fish. Soc. 93: 2734.CrossRefGoogle Scholar
Weidhaas, D. E. and Schmidt, C. H.. 1960. Toxicological action of DDT on three species of mosquito larvae. J. econ. Ent. 53: 106110.CrossRefGoogle Scholar