Breeding home range and habitat use of a rare high-elevation songbird in industrial forests of New Brunswick

Abstract

This thesis estimates home ranges, habitat selection, habitat use, and nest success of the Bicknell's Thrush (Catharus bicknelli), a threatened songbird species inhabiting industrial forests in north-central New Brunswick. Home ranges were estimated as 18.14 ± 5.33 ha (90% AKDE) for females, and 13.2 ± 2.2 ha (90% AKDE) for males. A population estimate, derived from the number of female home ranges within a potential habitat model, was calculated at 5 275 (4 077 – 7 469) individuals in New Brunswick. Compositional analysis showed significant habitat preference in both sexes at the home range vs. landscape level, but no significant preference at the relocations vs. home range level. Compositional analysis indicates that they prefer unthinned habitat but interactions between precommercial thinning treatments and year since the treatment increased likelihood of use as years increased. Different females showed different preferences to habitat, and 4/5 females nested in forest that had been thinned previously, with three of those nests succeeding. I discuss management and conservation implications of these results for this species in New Brunswick.