The spatial and temporal distribution of avian stick nests across a managed forest

Stick nests (as created by several forest dwelling birds) are valuable habitat features. Consequently, forest management practices in Western Canada often call for stick nests and the surrounding habitat to be conserved where possible. I examined historical distributions of stick nests across a working-forest landscape in west-central Alberta, to determine if locations as amassed by forest workers (1999 -2017) appeared randomly-distributed across the landscape or were biased towards specific habitat metrics, and if so, did these metrics change over time? I worked with three sets of data compiled from 1999, 2003, and 20152017, respectively. Biologically relevant and important management habitat metrics were compiled using the most relevant GIS layers corresponding to the years of stick-nest reporting. These metrics were calculated at five spatial scales: 25 m, 50 m, 100 m, 250 m, and 500 m. Identical data were collected from generated random (reference) sites paired with each stick nest site. I used conditional logistic regression to isolate the best predictors of stick nest occurrence in each time period, at each spatial scale. Models were successfully fitted for four of five spatial scales only in the 1999 time period. Deciduous cover was found to be a strong explanatory variable for stick nest locations at the 25 m and 50 m scale. Increased area of land-use (primarily oil and gas developments) and a high component of deciduous cover were found significant at the 100 m scale. The model generated for the 500 m scale indicated an increased likelihood of stick nests in areas with increased area of land-use, probably a result of both nesting behaviour and observer effects. The results of this study did not support the notion that habitat metrics associated with stick nests have remained constant (or changed) between 1999 and 2017 in the forest management area. A consistent and more thorough stick-nest monitoring program is likely required to fully understand the factors (natural and anthropogenic) linked to the conservation of stick nests across a working-forest landscape. Moreover, investing in these monitoring programs may help improve sustainable management practices over time by enhancing understanding of the complex influences of landscape management on raptor nesting behaviour.