Department of Physics, Chemistry and Biology (IFM)

The beetles in this study were sampled by using a non-harmful, pheromone (odour) based trapping method that allowed the beetles to be released alive once being counted. Therefore, traps where the catch is released alive are sometimes called "live traps". The pheromone solution is a mixture between the sex pheromone (R*,S*-2,3-hexanediol) and isopropanol, in which it is dissolved at a resulting concentration of 100 mg/ml, forming a transparent liquid with a weak smell of dissolvent. This non-lethal method was selected to minimise the impact on breeding and mortality in potentially fragile populations.

Traps were baited with pheromone between July 7^th and July 25^th 2014 directly on the trapping site, and these traps were called “activated traps”. The activated traps were generally re-visited after two or three days, depending on the weather conditions, from July 8^th to July 31^st. Activated traps were removed after the first catch, or left in the field for a maximum of 6-9 days.