“You have to convince the local people that it’s in their own interest to protect their forests,” Welch said in a 2015 TEDx talk. “If you don’t, you haven’t created something that’s really sustainable, that will last in the years to come.”

Welch first came to Madagascar in 1987, when the country’s government, after years of barring its doors to Western scientists, enlisted him and Katz to try to help rebuild Parc Ivoloina, which had been badly damaged by a cyclone the previous year.

Their first task was to help the park staff get more comfortable with the day-to-day care of the zoo’s captive lemurs, which had been confiscated from the illegal wildlife trade, and whose cages had been torn apart by the storm.

“But Andrea and I felt like there was a lot of potential there beyond that,” Welch said.

Building relationships and gaining trust took time. “We were pretty naive in the beginning,” Welch said. “We had to really learn that the conservation problems go back to poverty and people just trying to eke out a living on the land and feed their families.”

He joined the local Rotary Club. Gradually he learned to get by in French and a sprinkling of Malagasy, spoken with a southern drawl through his signature walrus mustache.

His lanky 6-foot-2 frame earned him the nickname “Lavabe.” “It means ‘big tall guy,’” Welch said.

Later, after their daughter was born, he became “Papa Alena.” “It’s common to call people by the name of their firstborn child,” Welch said. “I was happy to be Papa Alena.”

The couple would live and work in Madagascar for 15 years -- until 2004 -- both for the Duke Lemur Center and in partnership with the Madagascar Fauna and Flora Group, a consortium of zoos and other institutions committed to protecting wildlife in the country.

Over time, they and the Malagasy staff they trained took what had been a crumbling former forestry station with a single animal keeper, and transformed it into a nationally recognized center for conservation, captive breeding and environmental education with dozens of employees. Today its lemurs and other wildlife attract as many at 20,000 visitors a year.

In recognition of their service at Parc Ivoloina and later, at a reserve called Betampona, Welch and Katz were made “Knights of the National Order of Madagascar,” one of the government’s highest honors.

"It took our presence there year after year, working with people, building their confidence in us and in the projects and what we were all trying to accomplish,” Welch told Duke Today in 2004.

Welch grew up in the 1960s in Mississippi, and one of his first jobs in high school was at the Jackson zoo. He spent his summers there washing sidewalks, sodding grass, and unloading hay and feed for the animals. “It was mostly manual labor,” Welch said.

But over the years he worked his way up to being an animal keeper at other zoos in Georgia and Louisiana, and eventually he took a special interest in primates.

It was a chance visit to the Duke Primate Center, as it was then known, to exchange lemurs as part of a breeding program trade, where he met Katz.

Within a few years he had married and moved to North Carolina, earning a degree in zoology from North Carolina State University along the way.

While earning his degree he also worked as a field assistant for research projects on endangered spider monkeys and howler monkeys in Panama, Costa Rica and Ecuador, where he discovered he loved conservation and international field work.

“Loss of biodiversity is not a problem that’s unique to Madagascar. It’s not a problem that’s even unique to developing countries,” Welch told TEDxDuke in 2015.

“Extinction rates are a thousand times faster today than they were before humans were on the scene,” he said.

More than 500 species of birds, frogs, mammals and reptiles are known to have disappeared in the last century. Another 500 could be wiped out in the next two decades alone, according to one recent study.

Some of these species may be ones that pollinate our crops, or that keep pests or disease-carrying insects under control.

“Species are interconnected,” Welch said. “Very often, when one species goes extinct, it affects other species.”

Welch admits that conservation can be a bleak calling.

In Madagascar alone, as many as 99,000 hectares of forest are lost each year, most of it cut and burned to clear new land for farming. That’s roughly 15 football fields of forest lost every hour.

As the forest disappears, so does the habitat for Madagascar’s unique plants and animals. Nearly a third of all lemur species are now critically endangered.

What gives him hope, he said, is the overall heightened awareness of nature’s plight.

That’s another seed he planted: Many of the Malagasy students who participated in the early environmental education programs at Parc Ivoloina have since become decision-makers in their own right.

“The appreciation of environmental issues has changed dramatically since the 1980s,” Welch said. “There's this whole generation of young people in Madagascar that are enthused about protecting the environment, protecting wildlife, understanding biodiversity.”

Now when he goes back to Madagascar, the familiar sound of crowing roosters in the wee hours of the morning, and the smell of ripe clove buds or eucalyptus smoke, still feel like home.

For the past 13 years the Lemur Center has focused its conservation work in an area of relatively unspoiled rainforest in the northeast called the SAVA region.

Thanks to collaborations with Bass Connections, DukeEngage, and with faculty across campus, more than 100 Duke students have been involved in SAVA projects, ranging from investigating the health hazards of open-fire cooking to studying the link between deforestation and infectious disease.

After his retirement becomes official in summer 2025, Welch will stay involved with the Duke Lemur Center’s conservation work in an advisory role.

He also plans to lead another Duke Travels tour that includes both Madagascar and South Africa, and this time not by land but by sea.

“So it's not like I'm disappearing,” Welch said.

He’s looking forward to having more time for gardening, including managing the fruit and vegetable garden at the Duke Lemur Center.

“I call it a food forest,” Welch said, showing off rows and rows of sumac shrubs, persimmons, redbuds and pawpaw seedlings -- all of which will yield fresh greens for the center’s leaf-loving lemurs.

“We've got a lot to take care of," Welch said.