Although understanding dispersal ecology is important of Haemaphysalis longiconirs (Acari: Ixodidae) to control severe fever with thrombocytopenia syndrome, the small size of H. longicornis makes it challenging to study their behaviors. We examined the potential of fluorescent marking system (FMS) paired with an ultraviolet laser, an effective insect detection method, in tracking of H. longicornis. When we assessed potential effects of FMS on the survivorship and behavioral parameters including horizontal movement, vertical climbing height, and response to CO₂ of all development stages (larva, nymph, and adult) of H. longicornis, it did not induce any adverse effects on the hard ticks. Furthermore, we measured the detectable distance and detection rate of larvae, nymphs and adults to evaluate the detection efficacy of FMS. Using an ultraviolet laser, operators could detect the hard ticks from a distance ranging from 12 m (larva) to 29 m (adult). When the detection rate was measured in a grassland both during day and night, it was higher at night compared to day and increased with the body size. The detection rate was over 90% for all stages of the hard ticks at night, whereas larvae and nymphs showed that of 23% and 34% respectively during the day. However, the detection rate of adults was higher compared to other development stages regardless of time of experiment. Our results indicate that FMS can serve as a promising tool to track the hard ticks by providing reliable detection efficacy with no adverse effects on the marked individuals.

Both a fluorescent marking system (FMS) and a portable harmonic radar system (PHRS) are effective insect tracking methods. Prior to comparing their efficacies, we tested the viability of FMS in detection of an agricultural pest, Riptortus pedestris (Hemiptera: Alydidae); previous studies showed the harmlessness of PHRS on R. pedestris and its detection distance. Fluorescent marking allowed the detection of marked R. pedestris from > 25 m, when illuminated with a laser in the dark, while affecting only the vertical walking distance of the insect. Then, we assessed the efficacy of the FMS and PHRS as well as combining both methods (BOTH) in detection of R. pedestris in a grass field and a bean field during day and night. PHRS and BOTH showed higher detection rates than FMS in all settings, except for in the bean field at night. Also, although BOTH did not enhance total detection time, it facilitated the retrieval of the sample at night compared to only using PHRS.

Various techniques have been developed to monitor insect behavior in the field. Harmonic radar tagging is a promising method of tracking target insects because it can allow efficient detection of the insects with negligible effects on their behavior or physiology. However, availability of the light limits the effectiveness of the method as it is almost impossible to spot an insect in the dark. On the other hand, fluorescent-marking, when combined with strong light source, makes the organisms distinct at night in a non-destructive manner. Therefore, we conducted a field experiment to determine the effectiveness of the combination of the two methods. Riptortus pedestris (Fabricius) adults were marked with both harmonic radars and fluorescent paint. The marked insects were haphazardly arranged and pinned onto trees or the ground in the forest at night. Then, a group of paired researchers, one equipped with a harmonic radar and the other with a hand-held laser, attempted to find R. pedestris within 20 minutes. The detection rate showed a high variance ranging from 40% to 100%. Thus, with a proper training, harmonic radar system combined with fluorescent-marking can be a powerful technique to detect insects in the field. With these equipments, tracking insect behavior in the field will be more efficient in the dark.