Owls, Nightjars On The Decline In Iowa

Very common nocturnal birds are evidently on the decline around here.

It hasn't been that uncommon to go outside in Iowa at night and hear the call of owls. But that may become less frequent, according to the Iowa Department of Natural Resources.

Iowa DNR's Monitoring of Owls and Nightjars (MOON) keeps track of bird populations of owls and nightjars (another nocturnal bird) in Iowa, which is something they try to grow every year, with a hope of getting it to all 24 of Iowa's bird conservation areas. Since 2016, a lot of the species are listed as threatened or in greatest conservation need.

Only a handful of routes have longterm survey data, so there are a few unclear trends.

According to the 2025 report, which are surveys from May and June, numbers of barred owls are "stable to decreasing". Eastern whip-poor-wills are a species in great conservation need and Chuckwill's Widows are another threatened species in Iowa that's decreasing.

As for nightjars, the report said:

Although we can only make inferences at the scale of the survey, there are some concerning negative population trends emerging from our long-term routes, particularly with nightjars.

The Iowa DNR report said more research will need to be done to determine if there's any specific links between the owls and nightjar populations and wildlife management in the state.

The MOON survey is a DNR project that's open to volunteers, if you'd like to help call for these birds at night this summer. It'll be warm enough for it then.