Enamel-based mark performance for marking Chinese mystery snail Bellamya chinensis

The exoskeleton of gastropods provides a convenient surface for carrying marks, and in the interest of improving future marking methods our laboratory assessed the performance of an enamel paint. The endurance of the paint was also compared to other marking methods assessed in the past. We marked the shells of 30 adult Chinese mystery snails Bellamya chinensis and held them in an aquarium for 181 days. We observed no complete degradation of any enamel-paint mark during the 181 days. The enamel-paint mark was superior to a nail-polish mark, which lasted a median of 100 days. Enamel-paint marks also have a lower rate of loss (0.00 month^-1 181 days) than plastic bee tags (0.01 month^-1, 57 days), gouache paint (0.07 month^-1, 18.5 days), or car body paint from studies found in scientific literature. Legibility of enamel-paint marks had a median lifetime of 102 days. The use of enamel paint on the shells of gastropods is a viable option for studies lasting up to 6 months. Furthermore, visits to a capture-mark-recapture site 1 year after application of enamel-paint marks on B. chinensis shells produced several individuals on which the enamel paint was still visible, although further testing is required to clarify durability over longer periods.