Monkey Crossing

Golden lion tamarins were once common in parts of the Atlantic Forest. But for decades, people hunted them for food and because they thought the animals carried diseases. By the 1970s, fewer than 200 of the tamarins remained in the wild. So scientists began breeding them in zoos and releasing them into their natural habitat.  

Today, about 2,000 golden lion tamarins live in Brazil. But they’re still endangered. Part of the problem is that a major highway called BR-101 cuts right through parts of the forest where the animals live. “It’s impossible for the tamarins to cross the highway,” says Erin Willigan, the executive director of SavingSpecies. “They’re imprisoned on either side.”

Many golden lion tamarins once lived in the Atlantic Forest. But people hunted them for food for decades. They also thought the animals carried diseases. Fewer than 200 of the tamarins remained by the 1970s. So scientists began raising them in zoos. Then they released them into their natural habitat. 

Today, about 2,000 golden lion tamarins live in Brazil. But they’re still in danger of dying out. Part of the problem is the highway. It’s called BR-101. It cuts through the forest where the animals live. “It’s impossible for the tamarins to cross the highway,” says Erin Willigan. She runs SavingSpecies. “They’re imprisoned on either side.”

Scientists are teaming up to help the tamarins. They designed a bridge that will connect two sections of the tamarins’ habitat. The bridge will be covered with soil, grass, and trees to make it look like the natural forest (see A Bridge for Tamarins).

In the past few months, the scientists have been planting trees on each side of BR-101. When those trees mature, they will bring the edges of the forest right up to the sides of the bridge. Tamarins will be able to use the bridge to safely travel between two forested areas. “We’re going to bring families of tamarins closer to each other,” says Stuart Pimm, the president of SavingSpecies.

Scientists are teaming up to help the tamarins. They designed the new bridge. It will connect two parts of the tamarins’ habitat. Soil, grass, and trees will cover the bridge. That will make it look like the forest (see A Bridge for Tamarins).

The scientists have recently been planting trees. They placed them on each side of BR-101. The trees will grow larger over time. They’ll bring the forest edges to the sides of the bridge. Tamarins can cross the bridge. They’ll be able to move between the two forested areas. “We’re going to bring families of tamarins closer to each other,” says Stuart Pimm. He’s the president of SavingSpecies.

Connecting different tamarin populations will be good for the whole species. When animals mate, they pass along genes to their offspring. Populations of animals that have a diverse mix of genes are better able to fight off diseases.

The bridge in Brazil is mainly for the tamarins. But scientists expect other animals, such as wildcats, to use it too. Different species in an ecosystem depend on each other to survive. So protecting individual animals should  help preserve the biodiversity of the whole Atlantic Forest.   

Connecting tamarin groups will be good for the whole species. Animals pass along genes to their children when they mate. Some groups have a greater mix of genes. They’re better able to fight off diseases.

The bridge in Brazil is mainly for tamarins. But scientists think other animals will use it too. Saving one species, like tamarins, can help others. It could protect the biodiversity of the whole Atlantic Forest. Many creatures live in this ecosystem. They depend on each other to survive.

Paths that connect animal habitat, called wildlife corridors, have been built all over the world (see Making Connections). Some are bridges that traverse highways. Others are tunnels under roads. These paths help animals move around while avoiding cars.

Scientists hope that wildlife corridors will also help animals cope with climate change. As temperatures rise, animals will need to move to cooler places to survive. “If you’re imprisoned in an area, it’s going to be really hard to move,” Pimm says.  

Workers began constructing the bridge for the tamarins in November 2018. It’s just the first corridor that SavingSpecies wants built in the Atlantic Forest. The group hopes to connect other patches of trees where animals live. “With a large enough forest, golden lion tamarins have a good chance at survival,” Willigan says.

Paths linking animal habitats are called wildlife corridors. They’ve been built all over the world (see Making Connections). Some are bridges that span highways. Others are tunnels under roads. These paths help animals move around. They also help them avoid cars.

Scientists hope wildlife corridors help in another way. Climate change is causing temperatures to rise. Animals will need to move to cooler places to survive. “If you’re imprisoned in an area, it’s going to be really hard to move,” Pimm says. 

Work began on the tamarins’ bridge in November 2018. It’s the first corridor built by SavingSpecies. But the group wants to create more in the Atlantic Forest. That will connect other patches of trees where animals live. “With a large enough forest, golden lion tamarins have a good chance at survival,” Willigan says.