In the years 2004–08 surveys focused on insects registered a total of 345 beetle species, 421 species of butterflies, and 18 species of bees. This is considered a relatively low diversity compared to similar habitats of Denmark and Sweden. Still, some of the species found on the island are rare or threatened in the region. The population of butterflies seems peculiarly skewed towards regionally uncommon or rare species, including "Epiblema grandaevana" (a species of moth), and Bath White ("Pontia daplidice"). In 2005 the venomous Hobo spider was discovered here, a spider that is only regionally known from a certain spot in Jutland. It is thought that it migrated here by trains from abroad. In 2006, the beetle species "Ceutorhynchus resedae" was also discovered, a unique find in Denmark.