AUTHORS: Anna Buckardt Thomas, Iowa Department of Natural Resources; Riggs Wilson, Iowa Department of Natural Resources
ABSTRACT: Current state-wide bird monitoring programs in Iowa focus on diurnal species, and many data gaps exist in our understanding of nocturnal birds. Five owls and three nightjars are considered Species of Greatest Conservation Need in the state's Wildlife Action Plan, making the group a priority for monitoring and targeted habitat management. Since 2016, Iowa DNR staff have surveyed four nocturnal MOON (Monitoring Of Owls and Nightjars) routes twice each breeding season. This data collection has been in coordination with a similar citizen-science monitoring effort in Illinois, led by the Illinois Natural History Survey . That Iowa dataset is now reaching an age where it may soon be possible to detect changes in species population trends, but the data is geographically limited, and likely does not represent state-wide trends for these species. Over this time, high annual variation has been apparent for nightjars, with as few as 3 and as many as 21 Chuck-will's-widows detected on a single route, and as few as 53 and as many as 146 individuals detected in a given year across all four routes, for example. The number of owl detections however, have been much more consistent through time. In an effort to learn more about these nocturnal species on a state-wide scale, we increased monitoring efforts in 2024 to include14 routes within our Bird Conservation Areas (BCAs), and will continue to add routes again in 2025, with a goals of conducting MOON surveys all 23 of our BCAs. Our current information sets a base line for nocturnal bird populations in Iowa and has the potential to link species occupancy and abundance to habitat characteristics and management strategies into the future. The goal of this monitoring is to inform management of our BCAs to help maintain and increase populations of these declining species.
