Copulation between male and female small heath butterflies lasts between 10 minutes and 5 hours, occurring at any time in the day. In 1985, a study observed that males often mate within their own territory (86.7% of 30 matings), and these copulations are generally lengthy, lasting over 100 minutes. Otherwise, copulations lasted approximately 10–30 minutes, especially for vagrant males. The study also found that either the male or female (but generally the male) is forced to leave the territory after copulation.