May 08, 2023
By Andrew McKean
The song of this season around the country is the booming gobble of the wild turkey. Our waking hours are consumed with calling one into range, and our too-short nights are full of dreams of longbeards strutting right into our camouflaged laps.
How many of us think about hen turkeys in the spring? If we do at all, it's to cuss them for pulling otherwise interested toms away from our calls, or for offering gobblers the real thing instead of our unconvincing plastic decoys. But we should hold hens in higher regard, because the engine of prosperity for any turkey population depends on hens pulling off successful nesting attempts. And we'd be wise to recognize that the feats of patience, elusiveness and grit of hen turkeys are responsible for all our great days afield chasing toms.
Consider the wildly different lives that hens and toms lead. While male turkeys show off their plumage, spar with rivals, and dominate the landscape with their reckless gobbles, hens are doing their best to remain unseen. That's a character trait of hens, which must rely on their cryptic coloration and demure behavior to avoid attention. Then there's the challenge of actually cooking a new generation of turkeys—the incubation phase that puts hens in peril as they sit on their nests of eggs for three lonely and hazardous weeks.
Before I detail just how hazardous the incubation phase is, let's back up a piece, to both the big picture of wild turkey population dynamics and the very small picture of nest success. Big picture, wild turkeys are in a state of flux.
They went from being either gone from their core habitat or at exceedingly low numbers until the 1980s and '90s, to soaring populations in not only the heart of turkey country but secondary habitats as well. Whether that was an artificial high or not can be debated, but the new normal across turkey country is lower or at least highly variable populations. That dynamic applies to all the subspecies to some degree, but the swing has been especially noticeable with the Eastern gobbler, considered by many to be a favorite turkey to hunt.
The small picture might have something to do with that. While we're all focused on gobblers, the hens have a very different agenda. They're not strutting and gobbling. After they've been bred, they're all about making a nest and producing poults. Here's where the reality of habitat, food, predation, turkey densities and even hunting pressure all conspire to produce mixed results. It's a dynamic that Bret Collier, professor of wildlife ecology at Louisiana State University, has observed in his research.
Collier notes that most research over the past decades has been on recruitment, or the survival of young turkeys, as a way to understand turkey population dynamics. Specifically, research has focused on monitoring nests and trying to learn the conditions that lead to successful nesting, which is defined by the hatching of at least one egg, versus conditions that lead to an unsuccessful nesting attempt.
"Nest success is widely used as a proxy for the general productivity of populations each year," Collier wrote last year in Turkey Call magazine. "Nests are easy to find and monitor. Vegetation around the nest is easily measured. And we can use information from successful and unsuccessful nests to direct local-scale land-management activities."
But Collier says the standard conclusion that vegetation height, density and abundance are main determinants of nest success might be missing the point. Hens travel widely before selecting a nesting site, and that wandering might be intentional, a way to move away from their home ranges in case predators find the nest.
Once she starts laying eggs, a process that takes up to 14 days, the hen will move frequently, but in a smaller area of about 500 acres, around the nest. Collier says this might be because she's evaluating resources around the nest site and because she doesn't want to focus predators on her nest. But once the 26- to 28-day incubation phase begins, that hen is tied to her nest site, moving only infrequently and then in an area only about 30 acres in size.
"That 30 acres becomes the most important space in a hen's world, dictating her nesting success," says Collier. She's trying to stay beneath the notice of coyotes and foxes, snakes and raccoons, and even crows and hawks. It's not an easy life, and here's where vegetation cover or a specific lucky location might influence nest success. The rate of nest failure is astonishing.
"Based on the hundreds of hens we have monitored, about 20 to 25 percent of nests are successful in any given year, but it can be as low as 5 percent and as high as 50 percent," Collier says.
The main predators of turkey eggs and nesting hens differ by region. Coyotes are ubiquitous, but bobcats have a leading role in some areas of Texas and the Southeast. Raccoons and skunks take their share, and snakes, armadillos, foxes, feral hogs, owls, ravens and opossums all raid nests in certain areas.
If we kill the predators and varmints, then we should see higher turkey nest success, right? Maybe not, says Collier, who suggests that "nest predation likely is compensatory. Even if you remove all of one species of predator, another fills the void. Removing all potential nest predators at a manageable scale usually isn't an option because the community is diverse."
The idea of blaming predators for failed nests is as old as upland hunting and turkey calling. But maybe the main problem isn't predation, but rather inadequate habitat. Instead of carpet-bombing predators, Collier says, researchers should try to understand the types of areas where hens successfully nest and why those areas might have fewer predators. Maybe a certain predator species avoids certain vegetation types, or a hen chooses a microhabitat that is less likely to be detected and raided. This question of nest-success causality raises a sort of chicken-and-egg (or turkey-and-egg) question for researchers.
"Where the female locates the nest may be important for that nest's success, not because the vegetation she chose hid her from predators, but because predators avoid the particular vegetation where she put her nest," says Collier.
As available habitat becomes further fragmented with human development, these little islands of nest success will be increasingly important. We need them as much as those hardy hens that somehow, against all odds, pull off hatches and produce a new generation of foolish springtime gobblers for a new generation of turkey hunters.