Influence of Geomagnetic M-Index on Light-Trap Catch of Macrolepidoptera Species Selected from Different Families and Subfamilies

The study deals with the number of Macrolepidoptera species caught by light-trap, in connection with the geomagnetic M-index. We found close correlation between the nightly sum values of geomagnetic M-index and relative catch of Macrolepidoptera species separated from different families and subfamilies caught by light-traps of the Hungarian Forestry Light-Trap Network. Three behaviours were identified, but these behaviours do not depend on the taxonomic location of the species. We suggest that the geomagnetic M-indices provide more trouble-free spatial orientation of moths.