• Haseltine, Frank
  University of Maine Graduate School
  

A study was made of the population composition of several beaver colonies and of the rate at which the available woody plants were cut by two colonies. All beaver live-trapped during the population study were ear-tagged. The animals were retained in holding pens at each colony until it was believed that the entire family had been taken.

It was found that the normal colony which had been in existence three or more years contained in the fall the two adult beaver, a little of year-old beaver, and the litter of the year. Returns of ear-tagged animals animals by beaver trappers during the 1950 beaver trapping season showed that transplanted beaver of the same family will establish a new flowage by themselves even though released several days apart and only a short time prior to the freeze-up. The returns further showed that beaver will move considerable distances for unexplained reasons. The longest movement recorded is this study was 2.5 miles by a single two-year old female.

From the utilization studies it was determined that the greatest number of stems are out during the first year of a colony's existence - primarily because of lodge and dam construction. In succeeding years the number of stems out dropped, but more stems were cut for food than for construction. Alder, red maple. and aspen were utilized in that order of the number of stems cut. However, the order was recovered when considering the stems cut for food alone.