Liquid fluorophore taggants for mark-release-recapture research: A survey of potential arthropod targets

Authors: Hagler, James; Casey, Miles; Hull, Allya; Machtley, Scott

Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/6/2022
Publication Date: 8/22/2022
Citation: Hagler, J.R., Casey, M.T., Hull, A.M., Machtley, S.A. 2022. Liquid fluorophore taggants for mark-release-recapture research: A survey of potential arthropod targets. Entomologia Experimentalis et Applicata. 170:821-830. https://doi.org/10.1111/eea.13191.
DOI: https://doi.org/10.1111/eea.13191

Interpretive Summary: Tracking the movement of arthropod pests and their natural enemies is an essential component for developing efficient pest management strategies. Scientists at the ARS laboratory in Maricopa, Arizona developed a method to tag arthropods so that they can be tracked in their natural habitat. The taggants consisted of three colored glow-in-the-dark liquid fluorophores (green, magenta, and orange). Sixteen different species of arthropods were externally marked with the fluorophores and then qualitatively and quantitatively inspected for fluorescence. For the qualitative analysis, each specimen was examined by direct observation for the presence of fluorescence using a conventional ultraviolet (UV) light and a specialized UV light. The fluorophores were readily detected on many but not all the species examined. For the quantitative analysis, each arthropod specimen was measured for fluorescence using an automated fluorometer. Overall, the quantitative analysis was 100% effective at detecting fluorescence on a few species, effective on most species, and unreliable on several others. Overall, the results show that these fluorophores could be effective markers for many arthropod species and will provide a valuable methodology to track the dispersal patterns of arthropods.

Technical Abstract: We evaluated a method for marking arthropods that could serve as a valuable tool for mark-release-recapture type dispersal research. The taggants tested consisted of three liquid fluorophores labeled cartax green, magenta, and orange. The manufacturer markets these fluorescent markers as forensic theft deterrents. Sixteen genera of arthropods were externally marked with either one of the colored fluorophores or with water (negative control treatment). The specimens were then qualitatively and quantitatively inspected for fluorescence 24 hours later. For the qualitative analysis, three independent observers scored each specimen by direct observation for the presence of a fluorescent mark. The specimens were scored using a portable ultraviolet (UV) tube lantern and a specialized NIGHTSEA-brand LED UV light. The three fluorophores were readily detected on many but not all the species examined, regardless of the type of UV light used. Moreover, the NIGHTSEA LED light yielded fewer false-negative observer errors than the lantern. Each specimen's fluorescence was measured with an automated dual-wavelength microplate fluorometer for the quantitative analysis. Overall, the quantitative analysis was very reliable at detecting fluorescence on a few taxa (e.g., Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Chrysoperla spp. (Neuroptera: Chrysopidae), effective on most taxa, and unreliable on several others (e.g., Collops vittatus (Say) (Coleoptera: Melyridae), Geocoris spp. (Hemiptera: Geocoridae), Mecaphesa celer (Hentz) (Araneae: Thomisidae). The cartax green marker was more readily detected than the magenta and orange markers with both visual and automated detection. Overall, the results show that these fluorophores could be effective markers for many arthropod species.