UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

A simulation of predation by non-game birds on the mountain pine beetle (Dendroctonus ponderosae Hopkins) Korol, Jerome John


Available information on bird-lodgepole pine, bird-mountain pine beetle, and mountain pine beetle-lodgepole pine interactions was reviewed. A computer model was constructed for the purpose of simulating variations in these interactions. Three lodgepole pine stand structures and three sets of bird responses to changes in beetle density were simulated. It was determined that birds may be able to suppress beetle population growth and reduce maximum beetle density under 'typical' stand conditions, but could only prevent an epidemic when unrealistically high bird densities were assumed. Increasing base-line bird densities to levels which were realistically obtainable had effects similar to those obtained when predator efficiency was increased. No amount of avian predation could prevent a massive epidemic from occurring when stand conditions were such that beetle productivity was optimized. A mountain pine beetle epidemic, as well as bird functional and numerical responses, did not occur when a stand structure representing a preventive thinning was simulated. Preventive silvicultural methods such as thinning or reduction of rotation age, combined with practices such as retention of wildlife trees on clearcut sites in order to increase non-game bird densities, could help prevent endemic beetle populations from reaching epidemic levels.

Item Media

Item Citations and Data


For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.