- The larger and more apparent butterfly species are, and the longer flight periods and wider distributions they have, the earlier is their first discovery date.
- Abundance measures on the national project Butterflies for the New Millennium are higher for larger butterflies and lower for butterflies that are active on higher vegetation substrates (versus, say, ones that fly closer to the ground). Distribution on this project is positively correlated with visual apparency (ease of detection).
- The Butterfly Monitoring Scheme uses transect data to track changes in annual abundances. Abundance increases with dorsal basking postures (open versus closed wings) and use of lower vegetation substrates.
Dennis, R.L.H., T.G. Shreeve, N.J.B. Isaac, D.B. Roy, P.B. Hardy, R. Fox and J. Asher. 2006. The effects of visual apparency on bias in butterfly recording and monitoring. Biological Conservation 128:486-492.