Habitat de reproduction et succes de nidification d'une population introduite de Tetras du Canada, Falcipennis canadensis, dans l'ile d'Anticosti, Quebec

Abstract

Spruce Grouse (Falcipennis canadensis) were introduced on Anticosti Island in 1985 and 1986. This introduction provided an opportunity to study habitat utilization where low population density did not affect habitat selection. In order to study habitat utilization, eight females and six males were equipped with radio-transmitters. These birds were located on average once every 1.5 days between 18 May and 9 July 1986 for a total of 91 locations for the females and 103 for the males. Overall, sites used by Spruce Grouse were characterized by a dense shrub layer, particularly during nesting and brooding periods when compared with control sites. Males used a broader range of habitats when compared with females. The utilization of an open habitat during the breeding period compared to the other periods and may be related to the greater efficiency of the breeding display in such habitat. After the breeding period, males utilized sites having a denser tree and shrub layers, possibly to reduce predation risk as their flying capacity is reduced during molting. Females nest in sites having similar characteristics to those used by males during this period, seeking sites that can potentially reduce predation risk. Sites utilized during the first week of the brooding period were comparable to those used during the nesting period. However, during the second part of the brooding period, females moved to older stands characterized by lower tree and shrub densities. In the first year following introduction, nesting success was 62.5 percent. Results obtained in this study supported previous findings obtained in other regions and suggested that this introduction will be a success.