Mark-release-recapture provides a technique to estimate population sizes, dispersal, survival, and demographic data. This technique was employed with the small blister beetle, Gnathium minimum, at Spring Green Prairie State Natural Area from 24 July to 16 August 2008. Of 104 marked adults, 54 were recaptured; a maximum of 34 were observed during a single survey and a maximum daily Jolly-Seber population size estimate of 59 individuals was calculated. Most individuals remained within 12 m of their original capture location, suggesting they remained within the same patch of Helianthus occidentalis flowers or an adjacent patch. The furthest movement observed was 601 m.