natural landscape, in particular throughout the boreal forest. In an effort to better understand

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1 Boreal Chickadee [Poecile hudsonicus] Distribution & Habitat Associations in Alberta The Boreal Chickadee is a common, iconic and well-loved feature of Canada s natural landscape, in particular throughout the boreal forest. In an effort to better understand the detailed status of the Boreal Chickadee and other individual bird species in Alberta, the Alberta Biodiversity Monitoring Institute (ABMI) has partnered with the Boreal Avian Modelling (BAM) Project. Through this partnership we aim to develop a deeper understanding of how the management of wildlife habitat and human footprint* affect birds in the boreal forests of Alberta. This report focuses on our results for the Boreal Chickadee. General habitat associations found in our analyses corresponded well to existing expectations [SUMMARY] based on the natural history of this species 1. We found that the abundance of the Boreal Chickadee was highest in old coniferous forests and lowest in deciduous forest, regardless of forest age. Abundance declined sharply with increasing density of linear footprint (e.g., seismic lines and pipelines) in the landscape. Abundance also declined with increasing areas of forestry, agriculture and urban-industrial footprint when that footprint was in the immediate vicinity of the point count. As a result of our analyses, we can predict the Boreal Chickadee abundance to be lower in areas of Alberta where human footprint is the highest. *The ABMI defines human footprint as the visible conversion of native ecosystems by humans to support temporary or permanent residential, recreational, or industrial land use. Vegetation recovery in human footprints has not been incorporated in the present analyses. Photo credit: Wayne Lynch

2 The Boreal Chickadee is one of the few passerine species of North America that is a permanent resident of boreal forests. INTRODUCTION The Boreal Chickadee is one of the few landbirds in North America that is a permanent resident of boreal forest. This species occurs most frequently in coniferous forest, preferring spruce and balsam fir forest types 1. The northern edge of their range almost entirely coincides with the northern limit of white spruce forests. Boreal Chickadees nest in cavities that they excavate on their own or that they expand from existing natural cavities or old woodpecker holes 1. Boreal Chickadees typically nest in trees or snags that are characterized by softened heartwood but with a hardened outer shell of sapwood. OFFICIAL STATUS The Boreal Chickadee is listed as Secure by Alberta ESRD, and as Least Concern by IUCN (ver 3.1). RESULTS SUMMARY The compiled data sets of the ABMI, BAM, and the Breeding Bird Survey (BBS) included 19,659 point-count locations from Alberta. Boreal Chickadee was detected at 1,064 or 5.4% of all surveyed locations. The Boreal Chickadee generally forages in the forest canopy by gleaning for insects on conifer branches or by probing into bark, but will supplement their diet with seeds and berries 1. During the summer and fall, Boreal Chickadees often store food on the underside of branches which they can retrieve during the harsh winter months. Photo credit: Jason Cheever

3 The Boreal Chickadee occurence was highest in the Subalpine, Montane, Lower Foothills, Upper Foothills and Lower Boreal Highliands Natural Subregions. SPECIES OCCURRENCE The Boreal Chickadee occurred most often in the Rocky Mountain (1% occurrence), Foothills (8.9% occurrence), Boreal (5.8% occurrence), and Canadian Shield (4.3% occurrence) Natural Regions. In contrast, the Boreal Chickadee was nearly absent from the Parkland (0.3% occurrence) and Grassland Natural Regions (0% occurrence). Occurrence was highest (>8% occurrence) in the Subalpine, Montane, Lower Foothills, Upper Foothills, and Lower Boreal Highlands Natural Subregions. BAM data provided half of the detections which were concentrated mainly in the Central Mixedwood, Lower Foothills, and Lower Boreal Highlands Natural Subregions. Data from the ABMI and the BBS covered the remainder of the province. ABMI // 3

4 Habitat Associations ABMI / BOREAL CHICKADEE HABITAT ASSOCIATIONS The relative abundance of Boreal Chickadees was highest in older coniferous forest habitat, and lowest in deciduous forest irrespective of its age (Figure 1). Relative abundance of Boreal Chickadee generally increased with forest age in both coniferous and mixedwood forest types. Boreal Chickadee Abundance Years Since Last Disturbance Deciduous Pine Upland Spruce Lowland Spruce Mixedwood Figure 1. Abundance of Boreal Chickadees by forest type and age. Abundance was measured as number of individuals per hectare standardized to a scale of 0 to 1. Data source: ABMI, BAM, BBS, Alberta Vegetation Inventory, Grassland Vegetation Inventory, and the ABMI s provincial Human Footprint Inventory version Whiskers represent 90% confidence intervals. ABMI // 4

5 Response to Human Footprint ABMI / BOREAL CHICKADEE The abundance of the Boreal Chickadee (hereafter, abundance) showed a steep decline (nonlinear) in relation to the increased area of soft linear features (seismic lines, pipelines) near the pointcount stations. Abundance also declined when forestry, agriculture and urban-industrial footprint increased near the point-count station (Figure 2). Abundance Boreal Chickadee Percent Human Footprint Soft Linear (100 ha) Cultivation (7 ha) Forestry (7 ha) Urban Industrial (7 ha) Figure 2. Abundance of Boreal Chickadee as a function of percent human footprint. Abundance was measured as number of individuals per hectare standardized to a scale of 0 to 1. Shaded areas represent 90% confidence intervals. Data source: the ABMI field data, the ABMI s provincial Human Footprint/Habitat Inventory version (2007) clipped to 150m radius circles (7 ha) around each point-count and 1km 2 (100 ha) around each ABMI site centre. ABMI // 5

6 Mapping the Provincial Habitat Suitability of the Boreal Chickadee ABMI / BOREAL CHICKADEE Reference Habitat Suitability Current Habitat Suitability Change in Habitat Suitability Figure 3a. Predicted provincial reference conditions for Figure 3b. Predicted provincial habitat suitability for Boreal Boreal Chickadee calculated by statistically controlling Chickadees (circa 2007). Mean habitat suitability under (removing) human footprint effects. Mean habitat suitability current conditions was Data source: The ABMI s under reference conditions was Data source: the field data, the ABMI s provincial Human Footprint/Habitat ABMI s field data, the ABMI s provincial Human Footprint/ Inventory version (2007) and the ABMI s wall-to-wall Habitat Inventory version (2007) and the ABMI s wall-towall landcover (vegetation) map (circa 2000). Predictions made to a scale of provincial quarter sections (Alberta landcover (vegetation) map (circa 2000). Predictions are are made to a scale of provincial quarter sections (Alberta Township System). Township System). Figure 3c. The difference between reference conditions (Figure 3a) and current habitat suitability (Figure 3b) of the Boreal Chickadee in Alberta (circa 2007). Data source: The ABMI s field data, the ABMI s provincial Human Footprint/ Habitat Inventory version (2007) and the ABMI s wall-to-wall landcover (vegetation) map (circa 2000). The map is made to a scale of provincial quarter sthe ections (Alberta Township System). ABMI // 6

7 Mapping the Provincial Habitat Suitability of the Boreal Chickadee ABMI / BOREAL CHICKADEE CHANGE IN HABITAT SUITABILITY Using the statistical relationships defined in Figure 2 (between human footprint, habitat, and Boreal Chickadees), it is possible to create maps that empirically predict the habitat suitability of this species in every quarter section of the province (Figures 3a, 3b, and 3c). Mean habitat suitability across the province has decreased by 7.7% from reference (0.363) to current (0.336) conditions. Provincially, Boreal Chickadee habitat suitability was lowest in regions where agriculture, urbanization, and energy-related footprint was highest. No human footprint (i.e., human development or land use) is predicted to positively influence Boreal Chickadee abundance. POPULATION TRENDS According to BirdLife International s RedList assessment, the large range and population size of the Boreal Chickadee are above the thresholds for a Vulnerable listing under these two criteria. The overall population of Boreal Chickadees may be in decline but not, apparently, in Alberta 1. The ostensible decline is not sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion of the IUCN. The present data set is not suitable for temporal analysis for the following reasons: 1) The ABMI data set is not yet sufficient for temporal analysis 2) The BBS has inadequate coverage of the northern boreal forest in Alberta 3) The BAM uses information from specific research projects and thus does not provide estimates of long term temporal change REFERENCES Photo credit: Royal Alberta Museum 1. Ficken, M. S., M. A. Mclaren, and J. P. Hailman Boreal Chickadee (Poecile hudsonica), The Birds of North America Online. A. Poole, Ed. Ithaca: Cornell Laboratory of Ornithology; Retrieved from The Birds of North America Online database: http: bna.birds.cornell.edu/bna/species/ For more information on the Boreal Avian Modelling program and the North American Breeding Bird Survey please see and respectively. ABMI // 7

8 The ABMI & Next Steps THE ABMI The Alberta Biodiversity Monitoring Institute (ABMI) is an independent non profit organization that operates a long- term biodiversity monitoring program for Alberta. The ABMI monitors a network of 1656 terrestrial and wetland sites evenly spaced across the province, and also develops remote sensing products that provide data on land cover and land use at a province- wide scale and for a rectangular plots centered around each of the 1656 monitoring sites. The ABMI measures and reports on the state of biodiversity, habitat, and human footprint across the province using scientifically credible indicators of environmental health. Species data collected at the ABMI s sites includes: Terrestrial sites: breeding birds, trees, and soil samples (soil mites), vascular plants, mosses, and lichens Winter tracking sites: mammal tracking Wetland sites: vascular plants, vertebrate sightings, and aquatic invertebrates The ABMI is an independent and not-for-profit organization and is Canada s only province-wide monitoring program of this scale. The ABMI spearheads projects in Climate change adaptation Ecosystem services assessment Regional biodiversity planning and management (rare plant and animal monitoring design, Woodland Caribou conservation strategies NEXT STEPS The ABMI is a provincial biodiversity monitoring program designed specifically to track trends in landbird species such as the Boreal Chickadee. Coupled with programs like BAM, the ABMI s trend monitoring program is a powerful tool that directly supports land use planning, cumulative effects management, and species at risk management. The ABMI is designed to provide scientifically credible biodiversity trend information for hundreds of species across Alberta. As the ABMI s monitoring data continues to mature the following is expected: 1. Provincial trend data for greater than 100 landbird species including the Boreal Chickadee 2. Deeper scientific understanding of the relationship between landbird species and their habitats 3. Deeper scientific understanding of how current and future land use activities affect habitat and the species themselves 4. Comparable knowledge for hundreds of other native species including winter-active mammals, plants, moss, lichens, and wetlands ABMI data and information is freely available and is used in forest and oil sands stewardship reporting, land-use planning, establishing regional goals and baseline data, among other areas. Findings and reports are published on our website ( ABMI // 79