Observations on the behavior of Monochamus scutellatus (Coleoptera: Cerambycidae) in northern British Columbia

Authors

  • Jeremy D. Allison Centre for Environment Biology, Department of Biological Sciences Simon Fraser University 8888 University Drive Burnaby, BC V5A 1S6
  • John H. Borden Centre for Environment Biology, Department of Biological Sciences Simon Fraser University 8888 University Drive Burnaby, BC V5A 1S6

Abstract

The location, behavior, and sex were recorded for 329 whites potted sawyers, Monochamus scutellatus (Say), on horizontal host logs in a logyard in Ft. Nelson BC. Over 65% of all males and females observed, and 58% of oviposition, occurred on the sides of horizontal host logs. This behavior would minimize the costs of desiccation and slow development of progeny on the upper and lower sections of logs, respectively. The sex ratio was male-biased throughout the season, rising to 4.1 males per female on 5 August 2000. Copulation and oviposition peaked on 9 and 21 July, respectively. By 5 August copulation was no longer observed. A late-season increase in the proportion of mobile males may represent a change in male reproductive strategy from selecting a preferred oviposition site and waiting for female arrival, to active pursuit of increasingly scarce females.

Downloads