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Report by Calvin R. Fremling regarding the effects of various factors (including natural and human-driven) on mayfly population distribution on the Mississippi River. Introduction: "Burrowing mayflies are abundant along much of the Mississippi River (Plate 1.). Hoardes of imagoes and subimagoes often cause nuisance problems for river residents, motorists and towboat personnel (Fremling 1960, 1968). Yet, the three major burrowing species, Hexagenia bilineata (Say), Hexagenia limbata (Serville) and Pentagenia vittigera (Walsh), are not able to inhabit all sections of the river. Moreover, the distribution and relative abundance of the three species have apparently changed during the past 30 years. This report explains how various innate and environmental factors influence the distribution and relative abundance of the three species. It will also be demonstrated that mayfly distribution can be utilized to assess the well-being of a river which is so large that it cannot be monitored effectively or economically by standard methods." Article offprint from Proceedings of the First International Conference on Ephemeroptera (1973?). 16 pages. Part of the Cal R. Fremling Collection.

Publication Date


Item Type





Winona, Minnesota


Biologists; Upper Mississippi River; Mayflies; Pollution


Special Collections-Library



Rights Management

Requests to reproduce this image must be granted by the Winona County Historical Society.

Contributing Institution

Winona County History Center

Master File Format


Fiscal Sponsor

This project has been financed in part with funds provided by the State of Minnesota from the Arts and Cultural Heritage Fund through the Minnesota Historical Society.

Scanning Responsibility

Northern Micrographics

Date Digital

2019-06-24 00:00

Metadata Creation Responsibility

Anna Gaffey

Unique Identifier


Factors influencing the distribution of burrowing mayflies along the Mississippi River



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