Persistence and abundance of the Western Grebe (Aechmophorus occidentalis) in Alberta

• Author / Creator

  Erickson, Mara E

• The Western Grebe (Aechmophorus occidentalis, WEGR) is a Species of Special Concern in Alberta, declining in distribution and abundance. I evaluated how environmental variables including emergent vegetation, human developments, and prey availability affected WEGR persistence and abundance on 43 lakes in Alberta that historically supported WEGR. Persistence and abundance of WEGR were correlated, and both were positively associated with shoreline bulrush (Scirpus lacustris) and human development within a 500m buffer surrounding the lake, while inversely associated with surrounding forest. Bulrush provides important habitat for nesting, and WEGR are likely to occur on the same large fish-bearing lakes that humans prefer for recreation. However, this relationship with development puts grebes at risk for disturbance and habitat loss—a primary threat to endangered birds. I recommend shoreline vegetation be protected for the success of breeding grebes, and human activity around colonies should be kept to a minimum to curb further WEGR decline.

• Subjects / Keywords

  • Western Grebe
  • Persistence modelling
  • Aechmophorus occidentalis
  • Abundance modelling

• Graduation date

  Spring 2010

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3B033

• 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.