Forest Thinning Affects Reproduction in Pine Engravers (Coleoptera: Scolytidae) Breeding in Felled Lodgepole Pine Trees
Date
2001
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Entomological Society of America
Abstract
Reproduction in bark beetles (Coleoptera: Scolytidae) is known to be affected by
abiotic factors, especiallytemperature, and bythe qualityof individual beetles. Both of these factors
are affected byforest structure, yet the effects of forest structure on reproduction in bark beetles
have not been widelyshown in Þeld studies. Here we investigate how changes in forest structure
due to thinning of mature lodgepole pine, Pinus contorta variety latifolia Engelmann, stands affect
reproduction in pine engravers, Ips pini (Say), breeding in felled trees. To do this, we excavated pine
engraver gallerysy stems in thinned and unthinned stands at the end of the breeding season. Males
in thinned stands attracted more females than in unthinned stands. Also, females in thinned stands
extended their egg galleries farther, laid more eggs, and had higher egg densities than in unthinned
stands. These results are consistent with increased temperatures in thinned stands, but mayalso be
attributable to differences in individual qualityresulting from easier dispersal in thinned stands.
Regardless, the observed increases in reproduction likelyreßect higher reproductive success in
thinned stands than in unthinned stands, and the effects of thinning on population dynamics of bark
beetles should be further investigated.
Description
Keywords
Biology
Citation
"Forest Thinning Affects Reproduction in Pine Engravers (Coleoptera: Scolytidae) Breeding in Felled Lodgepole Pine Trees " T.D. Hindmarch, Mary L. Reid, Environ. Entomol. 30(5): 919-924 (2001)