Boreal Chickadee [Poecile Hudsonicus] Distribution & Habitat Associations in Alberta

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 species1. 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 The Boreal Chickadee is one of the few passerine species of North America that is a permanent resident of boreal forests.

INTRODUCTION OFFICIAL STATUS

The Boreal Chickadee is one of the few landbirds in North The Boreal Chickadee is listed as Secure by Alberta ESRD, and America that is a permanent resident of boreal forest. This as Least Concern by IUCN (ver 3.1). species occurs most frequently in coniferous forest, preferring spruce and balsam fir forest types1. The northern edge of their RESULTS SUMMARY range almost entirely coincides with the northern limit of white spruce forests. Boreal Chickadees nest in cavities that The compiled data sets of the ABMI, BAM, and the Breeding they excavate on their own or that they expand from existing Bird Survey (BBS) included 19,659 point-count locations from natural cavities or old woodpecker holes1. Boreal Chickadees Alberta. Boreal Chickadee was detected at 1,064 or 5.4% of all typically nest in trees or snags that are characterized by softened surveyed locations. heartwood but with a hardened outer shell of sapwood.

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 berries1. 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 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 Subregions. BAM data provided half of the detections which Mountain (10.4% occurrence), Foothills (8.9% occurrence), were concentrated mainly in the Central Mixedwood, Lower Boreal (5.8% occurrence), and Canadian Shield (4.3% Foothills, and Lower Boreal Highlands Natural Subregions. occurrence) Natural Regions. In contrast, the Boreal Chickadee Data from the ABMI and the BBS covered the remainder of the was nearly absent from the Parkland (0.3% occurrence) and province. Grassland Natural Regions (0% occurrence). Occurrence was highest (>8% occurrence) in the Subalpine, Montane, Lower Foothills, Upper Foothills, and Lower Boreal Highlands Natural

ABMI // 3 ABMI / BOREAL CHICKADEE Habitat Associations

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

1.2 Deciduous 1.0 0.8 0.6 0.4 0.2 0.0

1.2

1.0 Pine 0.8 0.6 0.4 0.2 0.0 Upland Spruce 1.2 1.0 0.8 0.6 0.4

Abundance 0.2 0.0 Lowland Spruce 1.2 1.0 0.8 0.6 0.4 0.2 0.0

1.2 Mixedwood 1.0 0.8 0.6 0.4 0.2 0.0 0−20 21−40 41−60 61−80 81−100 101−120 120−140 140+ Years Since Last Disturbance

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 2007. Whiskers represent 90% confidence intervals.

ABMI // 4 ABMI / BOREAL CHICKADEE Response to Human Footprint

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 point- count stations. Abundance also declined when forestry, agriculture and urban-industrial footprint increased near the point-count station (Figure 2).

Boreal Chickadee

1.0 Soft Linear (100 ha) 0.8 0.6 0.4 0.2

1.0 Cultivation (7 ha) 0.8 0.6 0.4 0.2

undance 1.0 Ab Forestry (7 ha) 0.8 0.6 0.4 0.2 Urban−Industrial (7 ha) Urban−Industrial 1.0 0.8 0.6 0.4 0.2

0 20 40 60 80 100 Percent Human Footprint

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 1km2 (100 ha) around each ABMI site centre.

ABMI // 5 Mapping the Provincial Habitat Suitability of the ABMI / BOREAL CHICKADEE Boreal Chickadee Township System). are of made to provincial a scale quarter (Alberta sections landcoverwall (vegetation) map (circa 2000). Predictions Habitat Inventory version (2007) and ABMI’s the wall-to- ABMI’s fielddata, the ABMI’s provincial Human Footprint/ under reference conditions was 0.363. Data source: the (removing) human footprint M effects. by calculated Chickadee Boreal statistically controlling Figure 3a. Predicted provincial reference conditions for Reference Habitat Suitability ean habitat suitability suitability habitat ean Township System). ofmade to provincial a scale quarter (Alberta sections landcover (vegetation) map (circa 2000) . Predictions are Inventory version (2007) and ABMI’s the wall-to-wall fielddata, the ABMI’s provincial Human Footprint/Habitat current conditions was 0.335. Data source: Th (circaChickadees 2007). Mean habitat suitability under Figure 3b. Predicted provincial habitat suitability for Boreal Current Habitat Suitability e ABMI’s System). of provinciala scale Township quarter sthe ections (Alberta landcover (vegetation) map (circa 2000). The map is made to Habitat Inventory version (2007) and ABMI’s the wall-to-wall ABMI’s fielddata, the ABMI’s provincial Human Footprint/ (circa 2007). Data source: in Alberta Chickadee Th Boreal (Figure 3a) and current habitat suitability (Figure 3b) of the Figure 3c. The difference between reference conditions Change in Habitat Suitability e

ABMI // 6 Mapping the Provincial Habitat Suitability of the ABMI / BOREAL CHICKADEE 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 Alberta1. 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 Photo credit: Royal Alberta Museum 2) The BBS has inadequate coverage of the northern boreal forest in Alberta 3) The BAM uses information from specific research REFERENCES projects and thus does not provide estimates of long term temporal change 1. Ficken, M. S., M. A. Mclaren, and J. P. Hailman. 1996. 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/254

2. For more information on the Boreal Avian Modelling program and the North American Breeding Bird Survey please see www.borealbirds.ca and www.pwrc.usgs.gov/BBS respectively.

ABMI // 7 The ABMI & Next Steps

THE ABMI NEXT STEPS

The Alberta Biodiversity Monitoring Institute (ABMI) is an The ABMI is a provincial biodiversity monitoring independent non‐profit organization that operates a long-term program designed specifically to track trends in landbird biodiversity monitoring program for Alberta. The ABMI monitors species such as the Boreal Chickadee. Coupled with a network of 1656 terrestrial and wetland sites evenly spaced across programs like BAM, the ABMI’s trend monitoring the province, and also develops remote sensing products that provide program is a powerful tool that directly supports land data on land cover and land use at a province-wide scale and for a use planning, cumulative effects management, and rectangular plots centered around each of the 1656 monitoring sites. species at risk management. The ABMI measures and reports on the state of biodiversity, habitat, and human footprint across the province using scientifically credible The ABMI is designed to provide scientifically credible indicators of environmental health. Species data collected at the biodiversity trend information for hundreds of species ABMI’s sites includes: across Alberta. As the ABMI’s monitoring data continues to mature the following is expected: • Terrestrial sites: breeding birds, trees, and soil samples (soil mites), vascular plants, mosses, and lichens 1. Provincial trend data for greater than 100 landbird • Winter tracking sites: mammal tracking species including the Boreal Chickadee • Wetland sites: vascular plants, vertebrate sightings, and aquatic invertebrates 2. Deeper scientific understanding of the relationship between landbird species and their habitats The ABMI is an independent and not-for-profit organization and is Canada’s only province-wide monitoring program of this scale. 3. Deeper scientific understanding of how current and future land use activities affect habitat and the The ABMI spearheads projects in species themselves

• Climate change adaptation 4. Comparable knowledge for hundreds of other • Ecosystem services assessment native species including winter-active mammals, • Regional biodiversity planning and management plants, moss, lichens, and wetlands (rare plant and animal monitoring design, Woodland Caribou conservation strategies

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 (www.abmi.ca).

ABMI // 79