A study in Germany found that over 40 years (1971-2011), populations of adults dropped rapidly in agricultural land, while dropping slightly less severely in native grasslands (although still decreasing by almost 83%).[3] The article stated that fragmented habitat protection does a poor job of securing biodiversity and protecting many species that are in peril, as it does not account for many species that cannot seek extra fragmented breeding sites.[3] Many species, including Boloria selene, fail to find good nesting sites as they cannot pass through the human habitat that divides suitable fragments.