Loss of wild turkeys concerning to all

Like many Iowans, I miss the familiar sights and sounds of wild turkeys this summer.

A hen’s instructions to her brood deepens the soothing quality of dawn on a remote stretch of river. The sight of turkeys flying single file across the river or pecking grit from a gravel bar provides welcome distraction from the monotony of non-biting fish. The flurry of wingbeats at dusk as turkeys fly up to roost subtly reminds an angler that it’s time get off the river.

In scores of river visits this summer, I have heard not a single cluck or peep, and I have seen but one hen flying across the river.

That’s a common complaint — turkeys missing from usual places and fewer of them where they are not totally absent, said Jim Coffey, the Department of Natural Resources’ turkey, deer and forest wildlife biologist.

For the past decade, Coffey and colleagues have noticed signs that Iowa’s wild turkey boom had passed its peak. Though the decline is far from a crash, it’s worrisome, he said.

“It’s not just an Iowa problem or a Midwest problem. The population decline is going on across the United States,” Coffey said.

Research is under way in several states, including Iowa, to identify the contributing factors.

“It’s never one thing. It’s always a combination of factors” that include disease, predators, weather, loss of habitat and even pests like black flies, he said.

Iowa researchers are targeting a relatively new wild turkey ailment, lymphoproliferative disease virus (LPDV).

“We were hoping to confirm that it is not here, but we have confirmed that it is,” he said.

Nationwide, the turkey population peaked at 6.7 million in the early 2000s and has since fallen to about 6.1 million, according to the National Wild Turkey Federation, which has helped state agencies restore flocks throughout the country.

The decline has been steepest in Missouri, which ranks with Wisconsin and Tennessee as the nation’s annual turkey harvest leaders. The Missouri Department of Conservation estimates the state’s population peaked at about 600,000 in the early 2000s and has since shrunk to about 350,000.

By some measures the decline in Iowa is not readily apparent. Just last year, Iowa hunters harvested a record 14,689 turkeys — a milestone attributable to a surge in license sales during the first year of the pandemic. This spring’s harvest — 11,697 turkeys — was consistent with the 11,129 spring harvest average from 2010 through 2019. The hunter success ratio for that same period has hovered near 22 percent.

Because few reliable wild turkey census techniques have been developed, biologists use hunter success rates, turkey harvest levels and age ratios of harvested birds to help define turkey populations. Productivity indices are constructed from reports of broods seen in July and August provided by cooperators through postcard and internet surveys.

Iowa’s wild turkey decline is perhaps most noticeable in the percentage of hens with broods and the number of poults per hen. In 2019, the most recent year for which statistics are available, the statewide average of hens with broods was 42.1 percent, down from the five-year average of 51.5 percent. In 2019, the number of poults per hen was 1.6, down from the five-year average of 2.1

The production declines were steepest in the state’s southern two-thirds. In southeast Iowa, for example, the percentage of hens with broods fell from the five-year-average of 51.6 to 21.4 in 2019, and the number of poults per hen fell from 2.1 to 0.8.

Coffey said the DNR anticipates no major changes in turkey seasons, license sales or harvest limits.