Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Environment and Society

Committee Chair(s)

Jessop B. Low


Jessop B. Low


The untimely death brought to a stop the work on his Master of Science degree and a termination of a promising career in the conservation field. Drowned in the line of duty was Roger Schmitke on June 10, 1965, in the Redwater River near Edmonton, Alberta, Canada.

Prior to his death, Roger had worked diligently on his research assignment and had collected all of the data deemed necessary for the completion of the thesis. Partial analysis of the data had been made. The present volume is an attempt to bring together his data and analyses for presentation to his graduate committee . It is understandably not in the form in which he meticulously would have presented it, but it does present the data on this important study. Many months of field research went into the project and additional time was spent in analysis of data.

It was a pleasure to have been associated with Roger and his family during his academic career at Utah State University. His pleasing personality and professional approach to the problem of the class and field were always refreshing and stimulating. It is with regrets that we must present this work instead of having Roger do so himself. Wherever possible, the text was retained in the wording of Roger.

Respectfully submitted,
J. B. Low
Major Professor


Annual productivity varied from 16.2 to 22.8 young per adult female based on placental scar counts. Summer juvenile mortality approximated 30 percent and annual mortality approximated 90 percent. Mortality of 90 percent each year resulted whether the population was trapped or not. Trapping took the place of other types of mortality. Adverse winter conditions were reflected in reduced muskrat body weights. Best quality furs were obtained in early winter - late October and November. Interspecific strife and food shortages appeared to be the most important mortality factors, although predation, movements, weather and parasites and diseases were known to have some adverse effect on the population. Most females produced two litters per season but some had three litters. Estimated density of 5.4 to 9.7 muskrats per acre was determined for the Big Island Lake marsh.