Often overshadowed by the flashier monarch, Karner blue butterflies suffer from a similar plight. Currently registered as Ohio’s only endangered butterfly, Karner blue’s have been reduced to just a fraction of the population that they used to have. Habitat destruction and fire suppression have severely limited the growth of their only host plant, wild lupine. Wild lupine grows best in a prairie setting and is quick to bounce back after being burned. When a fire rolls through, the visible parts of the lupine plant will burn away, but the roots will remain intact to send new shoots up shortly after. The loss of wildfires has increased forest canopy cover over many areas across their range and has inhibited the optimal growth of these plants.
The specific habitat that is necessary for both of these species to grow is an oak savannah, which is now considered one of the rarest ecosystems on earth. Oak savannahs are very dependant on fires to maintain balance, so when European settlers started suppressing fires, they nearly disappeared. The light tree cover allows the lupine to grow, as well as give the Karner blue caterpillers protection from the sun. In Ohio, Karner blue’s were extirpated by the late 1980’s, and it was not until 1998 that a captive-breeding and release plan was created. Several habitats in northern Ohio were restored and the Karner blue’s were reintroduced back into the Buckeye state. There has been a promising comeback so far with small populations taking hold again up north, but they still have a long way to go.
Ohio DNR Division of Wildlife. “Ohio.gov / Search.” Ohio DNR Division of Wildlife, wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/butterflies-skippers/karner-blue.
Grundel, Ralph, et al. “The Effect of Canopy Cover and Seasonal Change on Host Plant Quality for the Endangered Karner Blue Butterfly ( Lycaeidesmelissasamuelis ).” Oecologia, vol. 114, no. 2, 1998, pp. 243–250., doi:10.1007/s004420050442.
Meyer, Rachelle. “Lupinus Perennis.” US Forest Service, 2018, www.fs.fed.us/database/feis/plants/forb/lupper/all.html.
“Oak Savanna and Fire.” Forest Ecology Lab, 22 Dec. 2014, forestecology.cfans.umn.edu/research/savanna.
Image 1- ianadamsphotography.com
Images 2,3- http://www.karnerblue.org/KarnerBlue_FactSheet.html
Image 4- https://digthedunes.com/what-is-the-oak-savanna-and-why-is-it-so-important/