The Dependence of Normal and Black Light Type Trapping Results Upon the Wingspan of Moth Species

In the last decade several researchers found relation between the wingspan size of moths and their light sensitivity. Generally, moths with larger wingspan have higher light sensitivity. We tested these findings using the catch data of 378 Macrolepidoptera species from 19 black light (BL, 125 W) and normal light trap (100 W) pairs of the Hungarian Light Trap Network. We have found that wingspan size of about 25 mm is the limit below which some species were trapped more effectively by normal light trap, compared to BL. However, BL trap catch ratio of moths with wingspan of over about 35 mm is nearly 100 %, compared to normal light trap. According to the catch results of a site where normal and BL traps were placed close enough for the moths to perceive both at the same time, 75 % of moths with even small wingspan were caught by BL traps. Regarding the fact that BL traps collected significantly more individuals of Macrolepidoptera species with their wingspan over 35 mm on all sites of observation, we can conclude that Wolfram light bulb of 100 W is hardly suitable to use for this purpose. Consequently, considering our results, the light trap type can more effectively be specialized to the purpose of the observation according to the wingspan of the targeted species from which fact plant protection applications and entomological research projects can successfully benefit.