WINTER USE OF POWERLINE RIGHTS-OF-WAY BY MOOSE (ALCES ALCES)

Abstract

The objectives of this study were to determine the influence of a powerline right-of-way on moose abundance and to characterize winter food availability and use by moose (Alces alces) in rights-of-way. Moose tracks and trails observed in six 120 km long by 500 m wide plots including a right-of-way were compared to those on 6 similar plots which did not have a right-of-way (control). Helicopter surveys were done from mid-March to mid-April 1990 and 1991. Four surveys were conducted in 16 randomly selected yards (8 each year) located in rights-of-way. Between 70 and 90 4m² circular sampling plots were located in the right-of-way itself, while 90 sampling plots were located in the adjacent forest. All available and browsed twigs of all species generally used by moose were tabulated. A total of 95 signs of moose presence were observed in the 6 right-of-way linear sampling plots while 89 were observed in the control plots. The difference was not significant. In both the right-of-way and control plots, more than 75% of yards were located in habitats where the slope was gentle or absent. Half the yards were oriented between the southeast and the west. In right-of-way plots, winter yards were mainly located within 300 m of the closest water body. In the control areas, the majority of yards were located between 300 and 1,000 m from water. Finally, the majority of yards were located in mixed mature forest stands. The average browse production in rights-of-way was 43,495 twigs/ha while that of the adjacent forest was 115,020 twigs/ha. These means are significantly different. On average, 3,081 twigs/ha were browsed in rights-of-way while 1,193 twigs/ha were browsed in the adjacent forest. These means are not significantly different. The presence of rights-of-way did not seem to affect winter habitat selection or regional moose abundance. Results indicate that although rights-of-way studied were used by moose in winter, they did not offer very good feeding habitat, but neither did the adjacent forest habitat.