Effect of Flight and Winter Conditions on Adult Life History Traits of the Mountain Pine Beetle (Dendroctonus ponderosae Hopkins)

• Author / Creator

  Wu, Yiyang

• The mountain pine beetle, Dendroctonus ponderosae, represents a significant ecological and economic threat to North American forests. This study investigates multiple facets of the biology of D. ponderosae, focusing on metabolic rate, flight capacity, and host entry behaviour under varying winter conditions. I first test the impact of flight on the subsequent metabolic rate of adult D. ponderosae using respirometry. Results reveal that flight activity positively impacts the metabolic rate of D. ponderosae, showing increased CO2 production rate with flight distance and distinct respiratory patterns post-flight. My study is the first to identify distinct continuous and discontinuous gas exchange patterns in adult D. ponderosae, significantly influencing metabolic activity. Beetles with discontinuous respiration exhibit overall higher metabolic rates. I then test how exposing beetles to different winter conditions demonstrates that the duration and severity of overwintering during the larval stage influence the metabolic rate and respiratory behaviors of the adult D. ponderosae. Prolonged exposure to cold temperatures negatively affects metabolic rates in adult D. ponderosae, resulting in metabolic suppression and reduced CO2 production rates. My study highlights significant interactions between physiological state, environmental stressors, and metabolic regulation in adult D. ponderosae. Furthermore, my research shows that winter conditions and pre-flight physiological states significantly influence subsequent flight capacity in D. ponderosae. Heavier beetles show higher flight propensity and distance, with winter conditions having an indirect or secondary impact. Overwinter conditions do not affect the subsequent host entry of female D. ponderosae; instead, it is the weight of the females that influences their rates of host entry. This study is one of the first to explore how flight and winter conditions impact adult mountain pine beetle, providing insights that may help predict its spread as the climate changes.

• Subjects / Keywords

  • Flight capacity
  • Overwintering condition
  • Mountain Pine Beetle
  • Dendroctonus ponderosae
  • Adult life history traits

• Graduation date

  Fall 2024

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-0j3m-he66

• License

  This thesis is made available by the University of Alberta Library 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.