-produced aggregation pheromone of the bean flower thrips Megalurothrips sjostedti (Thysanoptera: Thripidae) . J. Chem. Ecol. 45 , 348 – 355 . Olaniran , O. A. and Kirk , W. D. J. ( 2012 ) Fightingbehaviour of male western flower thrips, Frankliniella
Adult male western flower thrips form mating aggregations within which fighting can occur between pairs of males. They may be defending a strategic position for mating. An understanding of this fighting behaviour, which is part of mating behaviour, may be useful for the development of novel methods of pest management. A bioassay was developed to observe male fighting and record it on video. The effect of male density on this behaviour was then investigated. Interactions consisted of either a brief contact with instant separation and no fighting or a longer contact with mutual abdominal flicking before separation. Fights usually lasted just a few seconds, but there were also many prolonged interactions with several bouts of abdominal flicking. The rate of brief contacts without fighting increased linearly with male density as expected because of the greater number of thrips in the arena. However, the rate of fighting and the duration of fights had a maximum at an intermediate male density, with less fighting and shorter fights at higher and lower densities, presumably reflecting the changes in the costs and benefits of fighting at different male densities. Observations suggested that a pheromone may be involved during fighting.
Aggressive behavior of white-eye mutant crickets was investigated and compared with that of wild-type crickets. In the dark, wild-type pairs performed long-lasting fights with significantly higher aggressive levels compared to those in the light. In contrast, fights between two white-eye mutants were not significantly different with those between two wild-type crickets both in duration and the aggressive levels. Ethograms of aggressive behavior showed that the mutants could show typical sequentially escalating fight with the same behavioral categories as the wild-type crickets. These results indicate that the white-eye mutants are able to express normal aggressive behavior.