Happy World Sparrow Day! Sparrows are humble heroes of the prairie, whether they migrate thousands of miles to their Central American wintering grounds and back, like the Grasshopper Sparrow, or live with us year round, whatever the weather, like the Song Sparrow, or stop over on their migration, like the Lincoln’s Sparrow. Sparrows exemplify an unassuming grace that contrasts with our beloved Sandhill and Whooping Cranes who so often steal the show on the Platte River. When the cranes have traveled north, however, sparrows arrive and stay to fill the spring with their exquisite songs. They make their homes and raise their families here as the days grow longer into summer, and when all goes well their fledglings, like the Grasshopper Sparrow pictured here, leave their nests to join the world.
Today our focus is the Grasshopper Sparrow, an indicator species for upland prairie birds and other biodiversity whose population has declined an alarming 68% across its historic range since 1970. Therefore, it has been designated as a species of conservation concern by the U.S. Fish and Wildlife Service. Most of its decline is likely due to the conversion of native prairie to cropland where Grasshopper Sparrows cannot survive or raise their chicks. The good news is that thanks to the Crane Trust’s protection of prairie habitat along the Platte River, we have them in abundance. We are currently studying how their populations respond to changes in temperature, rainfall, and land management to inform conservation efforts.
In a Crane Trust study led by Alex Glass, a biologist in our Monitoring Avian Productivity and Survivorship (MAPS) program and PhD student at Southern Illinois University, we have found that spring rainfall is the strongest predictor of Grasshopper Sparrow abundance, and that spring rainfall together with spring temperature is the strongest predictor of their successfully producing chicks. We also found that land management, specifically burning, has a significant influence on bird abundance during years of higher spring precipitation. Our findings demonstrate the importance of studying climate factors to inform bird conservation and the potential of land management actions to mitigate the negative effects of climate change. The Crane Trust is continuing to conduct research and manage land in order to protect and encourage the wonderful sparrows that grace our prairies with their songs.