Mating failure of female Parnassius smintheus butterflies: a component but not a demographic Allee effect. (Special Issue: Female mating failures.)

摘要

Female mating success affects the ecology, evolution, and conservation of species. From a population dynamic perspective, female mating failure occurring due to low population density potentially translates into negative population growth, resulting in population extinction. Despite the implications, there have been surprisingly few comprehensive studies of both the causes and the population level effects of female mating failure for insects. Herein, we examined the mating success of female Parnassius smintheus Doubleday (Lepidoptera: Papilionidae) butterflies and its effects on population growth. Using mark-recapture data amassed from 17 interconnected populations over 12 years, we assessed whether yearly female mating success varied with local population density, and whether population growth varied with mating success. We found that there was increased female mating failure at low population density - a component Allee effect. However, this effect did not result in a demographic Allee effect. We found that population growth was greatest at lowest densities and that there was no relationship between female mating success and population growth. These results along with a growing number of studies indicate that demographic Allee effects are much less common than component effects, and they may be relatively uncommon for insects in nature.Digital Object Identifier http://dx.doi.org/10.1111/j.1570-7458.2012.01279.x