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Hard Knocks: Going to Extremes to Study the Secretive Helmeted Woodpecker

By Tim Gallagher
From the Summer 2016 issue of Living Bird magazine.

We sit silently waiting, hunkered in a dense understory of bamboo and tree ferns in a remnant of the Atlantic Forest in northern Argentina, intently watching the entrance of a tree cavity some 50 feet high.

This may—or may not—be the active roost hole of a Helmeted Woodpecker, one of the most rare and secretive of Neotropical woodpeckers. It is nearly dusk, and mosquitoes and other biting insects are out in force, hordes of them buzzing incessantly around us, landing on our faces and necks, crawling into our eyes and ears, and there’s nothing we can do about it. Slapping at mosquitoes might spook the woodpecker if it’s nearby, so we do our best to ignore them. But just as I’m nearing the end of my endurance, a shadow passes over and a bird swoops up to the roost tree. With its cinnamon face and vivid shock of scarlet feathers rising Mohawk-style along the top of its head, the bird is absolutely stunning. It’s the first Helmeted Woodpecker I have ever seen.

It is October 2015—spring in South America—and I’m spending two weeks with Dutch ornithologist Martjan Lammertink at his Helmeted Woodpecker study site at Cruce Caballero Provincial Park in Argentina’s Misiones Provine, This small province is just a finger of land, about 60 miles wide and 180 miles long, in the far north of the country, protruding into southern Brazil with Paraguay to the west. Lammertink moved to Argentina in 2011 specifically to study these birds and the Atlantic Forest habitat on which they depend. He works as a researcher for Argentina’s National Scientific and Technical Research Council and is an associate of the Cornell Lab. During the field season, when he’s not at his research site at Cruce Caballero, he lives with his wife and two children in the town of San Pedro, which is only 18 miles away but takes an hour and a half to reach with a fourwheel-drive pickup because the roads are so poor. The main highway is a red mud road that dwindles to a narrow track once you enter the park. But it is spectacular country, a land of dense tropical forest with prehistoric-looking araucaria trees rising umbrella-like above the canopy.

The range of the Helmeted Woodpecker has been reduced by more than 95 percent due to deforestation. The red star marks Lammertink's study site. Map by Martjan Lammertink.
The range of the Helmeted Woodpecker has been reduced by more than 95 percent due to deforestation. The red star marks Lammertink's study site. Map by Martjan Lammertink.

Sadly, South America’s Atlantic Forest is one of the most threatened habitats on earth. Stretching along the Brazilian coast and inland through northern Argentina and Paraguay, the Atlantic Forest was originally larger than Texas, but it has been devastated by logging, agriculture, and the increasing human population in the area. Less than 10 percent of the original forest remains. For decades, we’ve all heard of the importance of the Amazon rainforest, but few recognize the rich, unique biodiversity of the Atlantic Forest. It is home to 936 bird species, of which 104 are threatened and about 140 are found nowhere else on Earth. In addition, hundreds of tree species thrive there, plus a vast assemblage of ferns, mosses, epiphytes, orchids, lianas, and bromeliads. Some 92 percent of the Atlantic Forest’s amphibians and 21 of its primate species are endemics.

One of the endemic birds—and the perfect poster child for this remarkable place—is the Helmeted Woodpecker. Like the habitat on which it depends, the bird is in serious trouble—but just how serious is difficult to say. The species is classified as vulnerable by the International Union for Conservation of Nature, but some researchers believe it should be reclassified as endangered. Estimates for the bird differ widely, ranging from only 400 individuals to more than 10,000. The uncertainty about their numbers is a measure of just how hard these secretive birds are to study.

“Except for about 10 to 20 minutes around sunrise, they almost never vocalize or drum and are one of the most cryptic woodpeckers in the world,” says Lammertink. And the subtropical forest they inhabit is dense, hot, uncomfortable, wet, and difficult to penetrate. But filling these gaps in knowledge has been Lammertink’s sole focus since 2011.

“The aim of my research is to identify the crucial tree species and tree conditions Helmeted Woodpeckers need for roosting, nesting, and foraging, and to provide guidelines for preserving and restoring these elements in logged areas,” says Lammertink. He hopes to determine at a landscape scale the minimum size of a forested area and how connected it must be to other forested areas to sustain Helmeted Woodpecker populations.

It’s not an easy job. Lammertink averages about 90 days a year in the field. And these are tough days, often involving 14-hour slogs from before dawn to well past dusk, sometimes in heavy rain.

The Helmeted Woodpecker is a perfect poster child for the remarkable Atlantic Forest. Like the habitat on which it depends, the bird is in serious trouble—but just how serious is difficult to say. Photo by Matjan Lammertink.

A Life of Woodpeckers

Hardship is nothing new to Lammertink. He has been obsessed with large woodpeckers since childhood, and his fascination has taken him to many exotic places. In his late teens, he worked after school at a dairy factory for 6 months to save enough money to self-fund a four-month expedition to the mountains of eastern Cuba to search for Ivory-billed Woodpeckers. That was in 1991, and he has since searched for ivory-bills twice more in Cuba as well as in the American South, where he was lead scientist in the Cornell Lab’s Ivory-billed Woodpecker Project. He has also searched multiple times for Mexico’s Imperial Woodpecker and has done extensive fieldwork on the Great Slaty Woodpecker in Southeast Asia.

Only a handful of Helmeted Woodpecker nests and roost holes have ever been found. A researcher could easily spend months in known Helmeted Woodpecker areas and only see one every six weeks. Lammertink quickly realized that the only possible solution would be to trap some of the birds and attach tiny radio-transmitters to them. Then he could follow and record their behavior throughout the day, and map out the extent of their territories.

The study began in 2011, but it was two years before Lammertink caught his first Helmeted Woodpecker. By 2013, he and field assistant Carlos Ferreyra and four macheteros had cut 39 miles of trails through the dense understory of bamboo and tree ferns. Lammertink and Ferreyra were running six trapping stations. It was frustrating work. The best they could get was an occasional fly-by. But finally, on August 8, 2013, an adult male landed in a tree nearby, and when they played a Helmeted Woodpecker call, it swooped down low, flying right into the net. They were in business.

A month later, they trapped a female right outside her roost hole—after two unsuccessful attempts in which she bounced off the mist net—and she turned out to be the mate of the male they’d already caught. They subsequently tracked the pair closely through the entire nesting cycle from the time they excavated their nest cavity until their single young fledged. Tracking this pair in 2013 yielded the most data on the natural history, behavior, and ecology of this species ever gathered. The following year the team captured three Helmeted Woodpeckers, as well as two Robust Woodpeckers and one Lineated Woodpecker—both similar, slightly larger, less endangered species. Lammertink will use the data he gathers on the two other species to make comparisons with the Helmeted Woodpecker in terms of their natural history, behavior, and habitat requirements.

The Atlantic Forest has three very similar looking woodpeckers, each from a separate genus: Helmeted Woodpecker (left), Lineated Woodpecker (middle), and Robust Woodpecker (right). Lammertink is radio-tracking all three so that he can compare their behavior, natural history, and ecological needs. Photos by Martjan Lammertink.

To Catch a Woodpecker

When I arrived at the site in October 2015, they did not have any transmitters on Helmeted Woodpeckers yet. They had tagged one earlier in the year, but they lost the transmitter when the bird molted a tail feather. Lammertink’s field assistants this time included grad student Juan Fernández and park ranger student Sebastian Sandullo (both in their twenties), and Valdir Gularte, a man in his early 60s who cuts trails, climbs trees, and performs other feats that would be impressive for a man half his age.

After I unpacked my gear in my tent, Lammertink showed me his telemetry equipment, consisting of a receiver about the size of a walkie-talkie, with an external directional antenna, and several tiny transmitters, which he attaches to one of the central tail feathers of any Helmeted Woodpeckers he manages to trap.

I was beside myself with excitement as we made our way to the first Helmeted Woodpecker nest. I’d never been in this part of Argentina before, so the Helmeted Woodpecker and a number of other local specialties—such as the Ochre-collared Piculet (a tiny woodpecker about the size of a kinglet), Robust Woodpecker (a relative of the famed Ivory-billed Woodpecker), Araucaria Tit-Spinetail (a pert little reddish-brown bird with a crest), and more—were all lifers for me. We drove on a rough, overgrown truck trail cut through the forest, stopping occasionally to let Gularte take a whack with his machete at the limbs drooping in our path.

We hiked down a steep, slippery machete trail through the forest. All of us wore knee-high rubber boots, partly for the mud but more to provide a modicum of protection against the area’s infamous fer-de-lance vipers. At least we were hiking in daylight and might have a chance to spot the snakes.

We finally arrived at the nest tree, but something was amiss: an animal had been gnawing around the entrance to the nest cavity trying to get at the eggs or young. Lammertink quickly took out a tiny video probe at the end of a telescoping metal pole that could extend to more than 50 feet in length. With this and a handheld video monitor, he could examine the nest contents without having to make a treacherous climb. Within a few minutes he had the probe positioned and the monitor lit up, showing the nest. There was nothing. The nest was empty.

Nest predation is a natural occurrence. Capuchin monkeys, various toucans and toucanets, as well as the raccoon-like coatis, routinely rob bird nests. The birds will simply excavate a new nest cavity and lay a second clutch of eggs. But for us, it was a potential disaster. These birds would not be returning to this cavity. We’d have to start all over again searching for their new nest.

Luckily, Lammertink knew where the male had previously roosted, before it lost its radio-tag. If the bird returned there to sleep, we might have a chance to trap him and track him to his new nest site. Lammertink estimated we had only three or four days at most before it began sleeping in a new nest cavity.

When we reached the roost tree after a long hike on a slippery trail, a major engineering task lay before us: to hack away the bamboo and other underbrush in a 15-x-20-foot rectangle to make room for the mist net. The foliage is so dense here it would be impossible to avoid getting the net tangled without cutting an open swath. This took hours, with four men working constantly in steaming heat while being bitten by aggressive flies and mosquitoes.

Lammertink already had a dozen or so flesh-eating botfly larvae embedded in his back. But this was just the beginning. They still needed to install a network of cords and pulleys so the mist net could be hauled up quickly and silently, as smoothly as hoisting a sail, in the predawn darkness. Lammertink started lobbing a heavy metal bolt tied to a cord high in the air, using a colossal slingshot to try to pitch it over a limb. The bolt sailed over the limb on his first try, and I started thinking this must be pretty easy. But the second one was a different story. The bolt fell short again and again and again. Then everyone started taking turns, trying to get the cord over the limb, but it was so high up that it was a tough shot. Finally, Gularte just grabbed the end of the cord, attached it to his belt, and started climbing up the massive tree, scurrying up as easily as a squirrel, using the vines growing along its trunk to haul himself aloft. He dropped the weight over the limb easily and let it slip down the other side.

A female Helmeted Woodpecker and her recently fledged juvenile look out from their shared roost cavity. Photo by Martjan Lammertink.
A female Helmeted Woodpecker and her recently fledged juvenile look out from their shared roost cavity. Photo by Martjan Lammertink.

Once in place, the net seemed perfect—well-placed and barely visible. As long as the bird flew in the proper direction when it left the roost hole, everything should be fine.

We spent the rest of the afternoon creating blinds from bamboo stalks and leaves. The entire process took 6 hours, using four men to do the work—an incredibly labor-intensive effort, which might not even result in the trapping of any birds. Lammertink estimates that only one out of three trapping attempts is successful.

I stayed at the roost hole with Lammertink for the rest of the day while the others walked back to camp. We wanted to make sure the woodpecker was roosting there before we left. As soon as the bird arrived and settled in, we slipped quietly away. Although it was nearly completely dark, we didn’t switch on our headlamps until we were a considerable distance from the roost, and tried our best to move silently.

We got up at 4:00 a.m. the following morning and returned to the roost hole—a tough trudge in the dark, struggling to avoid tripping on the vines that wound back and forth across the trail. I was nervous about stumbling upon a snake as we were hiking in the dark or while sitting in a blind waiting for the sun to come up. On these early morning treks out to a trap site, Lammertink always seemed so fleet of foot, moving swiftly and silently through the pitch-black forest. I couldn’t help thinking of Legolas from Lord of the Rings, dashing nimbly ahead as the mere humans, dwarves, and hobbits struggled to keep up.

When we got to within 150 yards or so of the roost hole, Lammertink signaled for us to stop and turn off our headlamps. From this point forward, we would proceed in complete darkness to avoid flushing the bird from its roost hole. But before doing that, we all went through a brief morning ritual, smearing DEET cream liberally around our ears, necks, and faces to help keep the biting insects at bay.

When we reached the site, I sat in a lookout spot as Fernández and Lammertink prepared the net. Shortly after dawn, the male Helmeted Woodpecker burst from the roost hole and flew immediately into the net, but within seconds the woodpecker had escaped. We would have to try again tomorrow.

Returning to camp we only had time for a quick cup of coffee before making a long trek downhill to another Helmeted Woodpecker nest. We saw the female leave the nest shortly after we arrived. Once again, the crew cut a clearing in the forest and installed the rigging for a net, and then we hiked back to camp.

Lammertink uses a handheld radio-telemetry receiver with a directional antenna to track the movements of radio-tagged woodpeckers at his study site. Photo by Tim Gallagher.

Another Day, Another Challenge

As the sun rose the next morning, we had already been sitting in the dark beside the Helmeted Woodpecker roost hole for nearly an hour, waiting to have another chance to trap him. We knew this could well be our final opportunity. It was a little later than yesterday when the bird finally popped out of the hole and started hitching around the tree trunk. I wondered whether he would think twice about flying in the direction of the net again, but habit was stronger than caution, and he flew swiftly into the net. This time it held the woodpecker securely. And he was beautiful, squawking loudly and pecking at us as we struggled to remove him.

This same bird had been caught earlier in the year and wore a white band on its leg. Lammertink carefully placed him in a black bag and weighed him using a spring scale. Then he opened the end of the bag just enough to expose the bird’s tail and began attaching a tiny radio-transmitter (weighing just 3 grams) to a central tail feather, using a small plastic cable tie and a drop of glue. (The bird would carry the transmitter for only a few months until it molted the tail feather.)

The entire process only took about 10 minutes, and the bird didn’t seem any the worse for wear. He flew to the trunk of a tree and sat there for a couple of minutes to regain his composure, then flew off through the woods. After that, we took down the net, cleaned it of debris and various insects it had caught, carefully packed away every piece of cord, and returned to camp. We would now have at least one Helmeted Woodpecker to track.

In the days that followed, the crew faced numerous obstacles: torrential rains that turned the camp into a mudhole—and filled the bottom of my tent with water; high winds that made it impossible to trap. One day we spent three hours standing in the pouring rain, trying to fix a badly tangled mist net. But we did manage to trap and radio-tag another Helmeted Woodpecker—a female—at the second trapping site. In the end, 2015 was Lammertink’s most successful season to date, and ended with seven birds tagged and tracked: two Lineated, two Robust, and three Helmeted woodpeckers.

A female Robust Woodpecker rockets out of her nest cavity. Lammertink’s research aims to understand why the Robust and Lineated woodpeckers that live in the Atlantic Forest don’t seem to be experiencing the kind of drastic population declines seen in the Helmeted Woodpecker. He has already shown that Helmeted Woodpeckers require larger territories than the other two species. Photo by Martjan Lammertink.

Halting the Decline of a Species

In some ways, Lammertink is an anachronism—the quintessential Victorian explorer, facing the same dangers and hardships his forebears went through more than a century ago. Even with modern technology, he works just as hard as they did, but his efforts are more effective.

Lammertink’s project is a work in progress and probably will be for years. But he has already gained important insights about these birds that will be vital to their conservation. The male and female of a Helmeted Woodpecker pair maintain separate territories with little overlap. And they have significantly larger territories than Robust and Lineated woodpeckers, even though Helmeted Woodpeckers are about one-third smaller. They also don’t seem to do as well in selectively logged forest.

This is the last season Lammertink will be working at Cruce Caballero, which has only 400 hectares of old-growth forest. He’s running out of new Helmeted Woodpecker pairs to follow. Next season he’ll be 53 kilometers away at Yaboty Biosphere Reserve, which has 9,000 hectares of old-growth plus a larger area of adjacent logged forest.

All in all, Lammertink is hopeful about the future of this species, at least in Argentina.

“During the 20th century, a network of protected areas covering nearly half of Argentina’s Atlantic Forest was created in Misiones,” says Lammertink. “The province has an adequate number of forest rangers, who effectively prevent logging in protected areas.”

Sadly, when you cross the border from Misiones into Brazil or Paraguay, most of the native Atlantic Forest is long gone.

“But the few areas of Atlantic Forest that remain in Brazil are well patrolled now and gradually recovering to old-growth conditions,” he says.

It would be naïve to think everything is rosy for the Helmeted Woodpecker, considering that more than 90 percent of the native Atlantic Forest has been destroyed. But at least the remnants are being protected now and conditions should improve in the years ahead. The rate of the bird’s population decline has slowed significantly since the second half of the 20th century, when logging was at its peak.

If wildlife agencies in Argentina, Brazil, and Paraguay make use of Lammertink’s research findings, there should be enough time to turn around the decline of these remarkable woodpeckers.

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