Impact à court terme de l'exploitation forestière sur le tétras du Canada (Falcipennis canadensis)

Abstract

Thirty-five and 22 spruce grouses (Falcipennis canadensis) were followed by telemetry, respectively 1 year before and the year of forest logging. Results indicate that the spruce grouse is negatively affected by clearcutting. After logging, spruce grouses moved to residual stands, near their spring home range. They were more often found in regenerating stands with higher shrub densities and in unproductive forests,selecting among available habitats, those supporting the highest tree densities and the lowest shrub densities. Movements of grouse increased during and after cutting. Summer home ranges averaged 23-41 ha during logging and 13-33 ha the year before cutting (p = 0.07). Home range areas were not statistically different before (4-21 ha) and after cutting (19-23 ha). Resting behaviour decreased and alert behaviour increased after logging (p > 0.01). Survival rate of grouse was lower the year of logging (S = 0.44 +/- 0.02), than in the preceding year (S = 0.75 +/- 0.01). It was also lower after logging (S = 0.50 +/- 0.02) than before forest operations (S = 0.89 +/- 0.09), with predation being the main cause of mortality. Grouse density decreased by 60% after logging.