(Iowa Capital Dispatch) A 2025 report on osprey nests, compiled by the Iowa Department of Natural Resources, shows a record year of observations for the species which was virtually nonexistent in the state prior to reintroduction efforts in 1997.
The nest monitoring program is primarily facilitated by volunteers who observe the nests several times during breeding and nesting season to determine if the nest was successful in fledging young osprey.
According to the latest report, 20 additional nests were monitored in 2025 than in 2024. In total, Iowans monitored 70 osprey nests in 2025 – 54 of which were active nests. In 2024, the state monitored 39 active nests.
In 2025, 30 nests were deemed successful, meaning at least one young bird survived to the age of being able to fly, compared to 25 successful nests in 2024.
The report said the growing number of nests show that osprey populations have increased in Iowa and so has nest reporting.
Ospreys are large birds that feed on fish, making them an indicator of stream and fish health. The birds have white underbellies with dark markings on their wings and around their eyes. The bird is also unique for its ability to close its nostrils when underwater, which aids in its ability to hunt for fish.
Osprey populations declined in the U.S. with the popularization of the chemical DDT in the 1950s, according to DNR. While populations rebounded slightly following the ban of DDT in the 1970s, the birds had to be reintroduced to Iowa.
From 1997 until 2016, juvenile birds were relocated from Minnesota and Wisconsin to strategic locations in Iowa. Now, ospreys return to Iowa to breed each year and the populations, according to observations from DNR, continue to increase.
Ospreys have a strong, recorded presence around Des Moines, in Black Hawk County, Dickinson County, Linn County and Johnson County, with some monitored nests on the state’s western edge.
According to the report, the new nests recorded this year were primarily around the Des Moines metropolitan area and in Black Hawk County near the Cedar Falls-Waterloo area.
While there were more overall nests monitored in 2025, the ratio of successful nests, at 56%, declined from 2024 when 64% of nests were successful.
Despite a lower success rate, the overall number of young ospreys that fledged increased from 47 in 2024 to 58 in 2025. Those figures are significantly higher than the observed survivals in 2021 through 2023, when an average of 29 young ospreys fledged.
Of the observed nests, 12, or 22%, had an unknown outcome, which is slightly lower than the percent of nests with an unknown outcome from 2024.
DNR, in the report, thanked the volunteers for their reporting and said the department will work to continue improving the figure in the future.
Osprey nests are typically located on tall structures – more than 80% of active nests in 2025 were on cellular towers. Iowans who spot an osprey nest in their area and are interested in helping to monitor the nest can contact DNR’s volunteer wildlife monitoring program.
