Boreal songbird response to understory protection harvesting in Alberta, Canada

  • Author / Creator
    Charchuk, Connor J
  • Understory protection is a harvesting approach that seeks to protect understory conifers during hardwood harvesting in mixedwood forests. While understory protection harvesting has been implemented for over a decade in Alberta, there has been no study of its ecological value to birds. We surveyed birds in understory protection (UP), natural disturbance harvest (NDH) blocks, and the nearby residual forest. We looked for differences in species richness and community composition between the three treatment types. We also conducted an in-depth analysis of the Brown Creeper, a species of songbird associated with mature coniferous forests. We found NDH had higher species richness than unharvested forests, but did not differ from UP. Higher richness in NDH may be due to birds being counted over an unlimited distance and the relatively higher sound transmission in NDH. The three treatments all had significantly different avian community compositions. UP represented an intermediary between NDH and unharvested forests. When comparing the oldest age class of UP with the unharvested forest, we found no significant difference in the bird communities just 12 years post-harvest. The Brown Creeper was shown to utilize UP to a small degree, and was more likely to use UP when spruce densities were higher. These results suggest that following understory protection harvest, the retained forest is quick to regenerate and provides habitat to mature forest species quite quickly. An expanded implementation of understory protection harvesting across the boreal forest may help mitigate some of the negative effects of timber management on habitat for forest dwelling birds.

  • Subjects / Keywords
  • Graduation date
    Spring 2018
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.