Bringing Back a Rare Butterfly

Fort Indiantown Gap near Harrisburg is the training ground for the Pennsylvania National Guard where soldiers practice with machine guns, tanks, and grenades. Over the years, the explosions have had unexpected consequences. They've maintained habitat for threatened wildlife. WPSU's Cynthia Berger reports as part of our series, Protecting Pennsylvania's Wildlife.

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Fort Indiantown Gap near Harrisburg is the training ground for the Pennsylvania National Guard where soldiers practice with machine guns, tanks, and grenades. Over the years, the explosions have had unexpected consequences. They've maintained habitat for threatened wildlife. WPSU's Cynthia Berger reports as part of our series, Protecting Pennsylvania's Wildlife.

On a sunny July morning, Joe Hovis stands in a grassy field studded with wildflowers Suddenly, military planes streak across the sky.

These are A-10 warthogs, tankbusters and they're preparing to forage.

By "forage" Hovis means that deep, rumbling sound

They are actually firing open rounds into the strafe pit.

Hovis is the Pennsylvania National Guard's wildlife manager. He says, one result of training with live rounds is that the grassy fields often catch on fire.

This range would catch fire once, twice, three times a year.

These training grounds were established in 1931. Since then, regular fires have, incidentally, maintained habitat for a rare butterfly. As the planes whoosh away, Penn State wildlife biologist Dave McNaughton, who works with Hovis, spots our target.

(whispers)
Stand really still, this is it right here, this is really unusual, he is probably a male.

Clinging to a grass stem is a butterfly with wings that are bright orange and chocolate brown.

McNaughton:
Usually they fly away when you get this close

The regal fritillary relies on certain grassland plants. Hovis says, the tiny caterpillars munch tender violet leaves. Butterflies sip nectar from native milkweeds and thistles.

With modern agriculture these plants get sprayed out. We are trying to manage this as a wet hayfield.

Another problem for the butterfly, says Hovis: grasslands like this one grow back into dense forest through natural succession. The net result: 200 years ago, regals were common in Pennsylvania farm fields. Today, the Gap is the only place in the state you still find the regal fritillary, though that could change.

(Car door slam, engine noise)
(John Ferrara)
We're heading to the main part of the park here, a popular area called the butterfly trail.

Two hours drive north, In Bald Eagle State Park, northeast of State College, John Ferrara steers his truck down a narrow dirt track. then brakes for a slow moving groundhog.


(Pennsylvania grizzly)

Ferrara is the park manager. He's working with the Fort Indiantown Gap team to reintroduce the regals on park land that used to be farmland.

It is rather exciting to be a part of it, to provide a small snapshot of what the landscape would have looked like a few hundred years ago.

One step is to cut down patches of non-native shrubs and trees, like autumn olive.

It's an invasive. It just blocks out everything else.

In place of the exotic invasives, Ferrara has planted a native grass. It creates the habitat tiny caterpillars need to over winter.

So you can see over here we have prepped the area and planted little bluestem in hopes of getting some established.

(Car door slam, gravel crunch)

Ferrara stops his truck by a patch of soil studded with rows of little colored flags. Each flag marks a tiny green plant.

Staff from Fort Indiantown Gap came here and planted more than 500 nectar plants.

We will have two other plots similar to that on the northern side.

Ferrara says, the plan is to release regal fritillaries in the butterfly habitat next year. But habitat improvements are already helping other wildlife. A bit farther up the road is a plot where invasive plants have been removed. A doe grazes with her fawn.

See that fawn three weeks old at most, that's a picture there, and they are in the area we are treating they are using this now the grasses are coming up. Those are the kinds of things I like to see, you know you are doing things the right way.

(Wood chipper sounds)

Back at the Gap, the wildlife team doesn't wait around for training activities to set fire to grasslandsóthey actively create butterfly habitat. One management technique is controlled burning of a field. Hovis drives a field where he's trying something equally dramatic.

(Wood chipper sounds up again)

(Hovis)
This is a 68 acre site and we're clearing out the pitch pine.

An industrial wood chipper is processing chunks of wood. The site is a field of dirt, studded with tree stumps.

How long till this is butterfly habitat? We are thinking three years.

Avoiding live rounds, setting fires, grinding up trees. Studying butterflies is not for the wimpy!

(Virginia Tilden)
There are other occupational hazards: briars, mosquitoes, not to mention live rattlesnakes.

(Walking through tall grass)

We've moved on to the hand grenade range, where Virginia Tilden is walking at a steady pace across another open field.

This is the best job a nature lover could have, I walk from point to point and count butterflies.

(walking in grass sounds)

Tilden's job is to count the butterflies, and, note their gender and behavior.

Another male flying to the left.

Not far away, at firing range formerly used by tanks, another team is counting butterflies in a different way.

(Door slam, gravel crunch)
(Hovis)
Right now we are in the middle of a mark recapture project here.

Mark recapture involves catching butterflies, measuring them, marking their wings with a Sharpie pen, and letting them go.

This is T-127, it's the 127th one I caught.

Biologist John Towser, holds a butterfly in one hand, his fingers gently pinching its orange wings up behind its back. With his other hand he holds metal calipers to measure the length of the body.

This is the trickiest part, it really doesn't want to cooperate.

Two weeks from now, the team will come back for more butterfly catching. They'll compare the number of marked to unmarked butterflies and get an estimate of population size.

(Swartz)
The fun part is trying to catch them, watching a bunch of grown men run around with butterfly nets.

Biologist Mark Swartz says fritillaries are pretty wily.

Some people will argue with me but I swear they know you have a net.

As another biologist demonstrate his skills with a net, Swartz does a play by play.

It looks like John has chased one from the bottom, up hill, swing, miss miss miss, can't say missed enough because they keep missing.

The guys do get their butterfly in the end. After all, butterfly biologists are not wimps. Thanks to the habitat work, butterfly numbers at Fort Indiantown Gap are stableóand expected to grow. And besides Bald Eagle State Forest, biologists are also working to bring the butterflies back at a military installation of a different sort: Gettysburg National Military Park.

Iím Cynthia Berger, WPSU.