Factors Influencing Mountain Pine Beetle (Coleoptera: Curculionidae: Scolytinae) Dispersal by Flight and Subsequent Trade-off Between Beetle Flight and Reproduction

• Author / Creator

  Wijerathna, Asha N

• The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), has an obligatory dispersal phase before selection of a suitable host for brood production. Flight during the dispersal phase is affected by both beetle physiology and environmental factors. Mountain pine beetle utilizes energy obtained during larval development and adult feeding before emergence from the natal tree host to fuel flight. Energy expenditure on flight may have consequences for subsequent reproduction. Mountain pine beetles were flown on computer-linked flight mills to establish how beetles utilize energy during flight and to determine how environmental conditions affect flight capacity. Mountain pine beetles utilize both lipids and carbohydrates to fuel the flight. Neutral lipids are the major fuel for flight. Beetles held at lower temperatures were more likely to fly and flew for longer distances than beetles held at warmer temperatures. Beetles increase flight distance and duration with day length. Beetles fly against wind speeds of 0-2 m/s in a wind tunnel. The effect of flight on subsequent reproduction was tested by introducing beetles flown on flight mills and un-flown control beetles into bolts of either lodgepole, Pinus contorta Douglas. ex. Loud. var. latifolia), or jack, Pinus banksiana Dougl., pine to reproduce. There is a trade-off between flight and reproduction in the mountain pine beetle as control beetles that did not fly produced a significantly higher number of offspring than flown beetles. The pine host that offspring were reared in affected the number of offspring and their condition, as more offspring emerged from jack pine but higher quality offspring emerged from lodgepole pine. Offspring from flown parents have a slightly lower body condition compared to the offspring from control adults. The study reveals physiological and environmental factors that influence dispersal capacity of mountain pine beetle and a trade-off between flight and reproduction in mountain pine beetle.

• Subjects / Keywords

  • Flight
  • Trade-off
  • Reproduction
  • Mountain Pine Beetle
  • Dispersal

• Graduation date

  Fall 2016

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3NZ80V8H

• 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.