| Recent evidence suggests that the spruce grouse is declining across its range in New York State. In this study, I examined the influence of habitat structure and composition on the distribution and movements of spruce grouse. I surveyed previously occupied (n = 30) and potentially occupied (n = 25) lowland coniferous forest patches for spruce grouse throughout the northern Adirondack Park Region. Grouse were observed at approximately half (n = 13) of the sites occupied from the period of 1976-1987 and at one new site. Greater amounts of black spruce (Picea mariana) scrub/shrub vegetation were found within home ranges (x¯ = 21.9%) versus random conifer patches (x¯ = 3.5%). Stand characteristics at spruce grouse sites with persistent versus extirpated populations consisted of significantly younger (x¯ = 45 versus 53 years, respectively) and shorter trees (x¯ = 11.2 versus 12.5 m), more live foliage cover in the 0.2-1.0 m range of the vertical strata (x¯ = 59.7 versus 36.3%) and more coniferous shrub cover (x¯ = 30.4 versus 18.7%), but less balsam fir (Abies balsamea) shrub cover (x¯ = 3.8 versus 11.6%). Occupied conifer patches were closer to other occupied patches than extirpated patches were to occupied patches. Findings support that (1) successional changes in the lowland boreal forest and (2) spatial arrangement of these patches in New York may influence spruce grouse site occupancy.;Keywords. Falcipennis canadensis, spruce grouse, habitat selection, home range, population decline, presence/absence, relative abundance, lowland boreal, peatland, bog, spruce-fir, insular population, isolation, natural succession, mid-successional, Adriondack Park, New York. |
