Research Highlights: The effects of fire on birds in the most northern parts of the boreal forest are understudied. We found distinct differences in bird communities with increasing fire severity in two vegetation types with naturally different burn severity. The highest severity burns tended to have communities dominated by generalist species, regardless of the original vegetation type. Background and Objectives: Wildfire is the primary natural disturbance in the boreal ecosystems of northwestern Canada. Increased wildfire frequency, extent, and severity are expected with climate change in this region. In particular, the proportion of burns that are high severity and the area of peatlands burned are increasing, and how this influences birds is poorly understood. Materials and Methods: We quantified the effects of burn severity (low, moderate, and high severity) in uplands and peatlands on occupancy, density, richness, community composition, and functional diversity using point counts (n = 1158) from the first two years post-fire for two large fires in the Northwest Territories, Canada. Results: Burn severity had a significant effect on the occupancy and density of 86% of our focal species (n = 20). Responses to burn severity depended on vegetation type for four of the 18 species using occupancy and seven of the 18 using density, but were typically in a similar direction. Species richness and functional diversity were lower in areas of high severity burns than unburned areas and low severity burns in peatlands. Richness was not related to severity in uplands, but functional diversity was. Peatlands had higher species richness than uplands in all burn severities, but as burn severity increased the upland and peatland communities became more similar. Conclusions: Our results suggest that high severity burns in both vegetation types support five generalist species and two fire specialists that may benefit from alterations in vegetation structure as a result of climate induced changes to fire regimes. However, eight species avoided burns, particularly birds preferring peatlands, and are likely to be more susceptible to fire-driven changes to their habitat caused by climate change. Understanding the long-term risks to these species from climate change requires additional efforts that link fire to bird populations.
Related Resources
A Regional-Scale Index for Assessing the Exposure of Drinking-Water Sources to Wildfires
Resource Date:
April
2019
Utilizing a Topographic Moisture Index to Characterize Understory Vegetation Patterns in the Boreal Forest
Resource Date:
September
2019
Organization
Short-Interval Wildfire and Drought Overwhelm Boreal Forest Resilience
Resource Date:
December
2019
Protocols for Monitoring Ecological Recovery of Reclaimed Well Pads on Grasslands
Resource Date:
2019
Organization
Development of a Model Ensemble to Predict Peary Caribou Populations in the Canadian Arctic Archipelago
Resource Date:
December
2019
Monitoring Ecological Recovery of Reclaimed Wellsites: Protocols for Quantifying Recovery on Forested Lands
Resource Date:
2019
Organization
Was this helpful?
|