Column: Understanding turkey biology can make you a better hunter | Outdoors

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Known as a big bird with a little brain, wild turkeys have a terrible reputation for being a dumb animal. However, if you’ve ever tried to hunt them, you probably know turkeys are anything but dumb.

One of the best ways to defend their smarts is to look at a turkey’s vocabulary, which is comprised of 11 unique vocalizations according to the Cornell University’s Lab of Ornithology. Most animals make sounds, but a truly dumb animal wouldn’t have the need or ability to produce such a complex range of sounds.

Their conservation success story also gains them intelligence points. In the early 20th century there were only about 30,000 wild turkeys left on the continent. Today, however, more than 7 million wild turkeys inhabit North America, according to population estimates from the National Wild Turkey Federation.

Much of this triumph is thanks to the turkey’s smarts and ability to adapt, but it’s also due to the advanced biological characteristics that help them survive on a daily basis, especially during hunting season.

Eyes and Ears

Turkeys have some of the finest eyesight in the animal kingdom, which is a reputation they’ve had for a long time.

With eyes on the side of their head, turkeys can see 270 degrees at any given time. When you consider how a turkey nervously bobs its head and rotates its neck, it’s almost constantly taking in what’s going on a full 360 degrees around it.

Most birds see in color, and turkeys are no exception, relying heavily on color vision to find mates and detect predators. Their eyes are composed of seven different types of photoreceptors and six different types of cones. For comparison, humans only have four different types of photoreceptors and three single cones.

One of the cones turkeys possess has spectral sensitivity to wavelengths near 400 nanometers, which falls in the UV-light range. This extended view of the color spectrum allows them to pick up things that human eyes can’t, such as the phosphates in laundry detergent that create a bright, blue glow around otherwise camouflaged hunters who aren’t mindful of their laundry habits.

What turkeys lack, though, is the ability to see well at night. The abundance of cones that allows them to see such detailed colors means their eyes lack rods, the visual cells associated with night vision. This is why turkeys are often overcautious with their roosting habits, flying to the treetops before the sun sets and then not flying down in the mornings until after first light.

That lack of low-light sight is why it’s so common for turkey hunters to set up really early in the morning, sometimes an hour or more before dawn. But this doesn’t mean hunters can wander too close to the roost in the dark, because turkeys still have a great sense of hearing.

A wild turkey’s ear biology is fairly similar to a human’s, as it has an outer ear, middle ear and inner ear. A turkey’s outer ear is the small hole in the side of its head, which is less efficient than a human ear at gathering sound due to the lack of pinna, which is the external part of the ear often associated with mammals — think of ear lobes. The purpose of pinna is to funnel and concentrate sound waves, something that turkeys struggle to do.

However, bird species also have a single structure of bone and cartilage called columella in their ears that dramatically speeds up how quickly they process sound. While humans hear sounds in bytes about 1/20 of a second long, columella helps birds process sound at up to 1/200 of a second. That gives turkeys the ability to hear much shorter notes, where one note to us equals 10 notes to them.

All that points to why hunters often fawn at great turkey calls and callers. The yelps and cutts you make on your turkey calls each spring might sound spot on to you, but the masterful ears of a tom tell him otherwise.

Feathers and legs

If a turkey learns through visual or audible cues that something isn’t right, it’s likely they’ll leap into flight. While flying may look like a real chore for turkeys, they’re actually quite good at it. They’re capable of going over a mile at a time by alternating wing beats and gliding.

They still have their limitations, though, and can only carry on with continuous wing beats for a couple hundred yards. Once they gain flight, they’re capable of reaching speeds up to 50 mph.

Like pheasants, however, wild turkeys have a run-first, fly-second mentality, and they’ve been documented running up to 25 mph. That’s only 3 mph slower than what Usain Bolt was clocked at during his gold-medal performance in the 100-meter dash in the 2016 Olympics.

There are a couple factors that help make turkeys ideal track stars. One of them is how their tendons are structured, and to better understand how turkeys cover so much ground, a study was done to observe the impact that their leg tendons take when compressed. To do this, researchers dropped turkeys from 5 feet in the air and observed the landings with foil-strain gauges glued to the turkeys’ legs.

Observers noted that a turkey’s tendons protect surrounding muscle fibers by absorbing energy from a hard landing before releasing it back to surrounding muscles more slowly. This process is perfect for a specimen that needs to make quick escapes or catapult itself into flight.

Outdoor Forum columnist Spencer Neuharth is from Menno, studied biology at the University of South Dakota and worked as a fish biologist for five years.

Firearms turkey seasons open Saturday

The state’s archery turkey season opened April 7, and the firearms turkey season for prairie, Custer State Park and Black Hills hunting units will kick off Saturday morning.

Regardless of season, shooting hours are a half-hour before sunrise to sunset, and spring turkey seasons close May 20.

South Dakota had its first turkey hunting season in Fall 1954 in the Black Hills. During the nine-day season, roughly 135 turkeys were killed by 750 licensed hunters.

The state’s turkey population grew steadily in the following years before reaching its height in 2010, when the reported hunters killed 9,856 birds during the spring season. Since then, however, the turkey population and harvest success rates have steadily declined, with hunters reporting they killed 5,029 turkeys during the 2017 spring season.

Source: South Dakota Game, Fish and Parks Department



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