Surveys by the Iowa Department of Natural Resources show Iowa’s bald eagle population is continuing to grow. Stephanie Shepherd at the D.N.R’s Wildlife Research Station in Boone says 47 new bald eagle territories have been reported this year in Iowa, along with about 60 new nests each of the past couple years.

“These aren’t necessarily nests that were built that year, but they were reported new in that year. So we’re still adding new territories for sure,” Shepherd says. Bald eagles had disappeared from the state by the early 1900s. But their numbers have improved since the late 1970s, following a national ban on the pesticide D.D.T. and other recovery efforts.

Eagles prefer areas along rivers with plenty of food sources and large, sturdy trees for nesting, but Shepherd says the eagles appear to be adapting to all areas. Shepherd says the eagles have been showing up in some not-so-ideal places and they seem to be successful. Shepherd says most of the data on eagles in Iowa is collected by volunteers.

They are most heavily concentrated along the upper Mississippi River, particularly in Allamakee  County. Wildlife experts say Iowa’s bald eagles are currently threatened by lead poisoning from consuming the carcasses of deer and other game that has been killed with lead shot.