Studies examining impacts of land cover typically focus on abundance, distribution, and/or community richness, overlooking underlying demographic processes such as survival or reproduction. Here, we present findings from a unique dataset that allowed us to measure the relationship between land cover and reproductive output across the distribution of the Mourning Dove (Zenaida macroura). We used hunter-derived, Mourning Dove wing data across 1,271 counties in the United States from 2008 to 2014 to estimate spatially explicit age ratios (juveniles: adults), an index of local reproductive output. We also used raster imagery data to estimate relationships between reproductive output and land cover and crop cover. We found that low reproductive output occurs in regions where Mourning Dove declines have been steepest. Our findings reveal that impacts of land cover vary geographically, but even at a coarse resolution, small changes in the relative proportion of human-dominated landscapes can have a significant impact on the reproductive output of this generalist species. Maize and soybean systems correlate with up to a 57% reduction in Mourning Dove reproductive output in the eastern United States. In the western United States, developed areas correlate with a 41% increase in reproductive output. Across the United States, native habitats had neutral or negative relationships with age ratios. Our study contributes continental-scale evidence that Mourning Dove reproductive output is largely driven by human-dominated land cover including agricultural and residential areas. With Mourning Doves declining across the range, discerning more fine-scale land cover factors is critical for ensuring Mourning Dove populations persist into the future.