Visible implant elastomer as a viable marking technique for common mistfrogs (Litoria rheocola)

Mark–recapture studies are often used to quantify rates of recruitment and survival, growth rates and patterns, and individual movement, among other things. Marking techniques must satisfy several criteria—marks should: (1) not affect the behavior or survival of individuals; (2) not cause undue pain or stress; (3) last as long as the study; and (4) be easily identifiable. Visible implant elastomer (VIE) tags can be used to mark vertebrates, including amphibians, but can move under the skin, potentially affecting readability and resulting estimates of dispersal and survival. We examined the effectiveness of VIE as a marking technique for Common Mistfrogs (Litoria rheocola) in the field over 1 yr. We determined the readability of marks over time, and evaluated effects of marking on measurements of frog movement. If marking affected mobility of the marked rear limb, we expected that subjects marked in both legs would be more strongly affected (thus, individuals should move less often), or should move shorter distances, than subjects marked in only one leg. We marked 1392 animals under the skin of the thighs in either the right, left, or both legs and recaptured 255 subjects at least once. We found that 84% of marks remained readable after 1 yr. Movement parameters were very similar between frogs marked in one or two legs. We conclude that VIE is a safe and effective marking technique for long-term amphibian studies, especially for stream-associated hylid frogs