In Chile’s far south, scientists record an island’s quickly shifting ecology

This story is the first part of a Mongabay series titled “Climate Crisis in Cape Horn” that won the Inter American Press Association Award for Excellence in Journalism in the Chronicle category, in September 2023. You can read the other stories in the series in Spanish on Mongabay’s Latam website here.

Punta Arenas and Navarino, CHILE — In Punta Arenas, Chile, the confusing temperature sensations are the first thing we notice. The subantarctic wind hits our bodies with force, and from time to time, smacks us in the face like a slap, so we must bundle up in good jackets and hats. At our backs, by contrast, where the wind is blocked, the January sun pricks its rays into our calves like tiny needles. So we, 80 people waiting for the ferry in Punta Arenas, feel hot and cold at the same time.

Among the group are locals, people who live in Puerto Williams, the last city on the continent before Antarctica, which it will take us 30 hours to reach. The rest are mainly French, English, Swiss and Chilean tourists, all equipped with mountain gear, who are preparing to walk for five days through the Dientes de Navarino, a group of mountains that resembles a set of teeth due to its rocky, pointed peaks.

Puerto Williams and the Dientes de Navarino are located on Navarino Island, in the last commune in the far south of Chile, Cabo de Hornos. We’re all going to the same place, though the Mongabay Latam team has other plans: find out what scientists investigating the area’s insects, birds, plants and climate — which in some parts is as cold as Antarctica — are learning.

We set sail at 6 p.m. The sky is perfectly blue, without a single cloud, and the sea of the Strait of Magellan is so calm that it is difficult to distinguish where the sea ends and the sky begins on the horizon. After a few minutes, a pod of Chilean dolphins (Cephalorhynchus eutropia) jumps out of the water, dives down, swims around and then jumps again, accompanying the ferry.

We are excited and expectant. If this is how our trip to the end of the world begins, how else will this journey through the channels of Patagonia surprise us?

Thirty hours of navigation

At almost 11 p.m., the sky still hasn’t darkened, even though the sun set over the hills more than an hour ago. But the morning arrives early, at around 5 a.m., by which point the ferry is already sailing through the fjords of the Cape Horn Biosphere Reserve.

The fjords are deep, narrow valleys that were hollowed out by ice during the ice age. When the ice retreated some 20,000 years ago, the sea flooded in. An aerial view of the landscape shows a labyrinth of water and bits of land that form the Fuegian Archipelago, where the planet’s southernmost temperate forests grow, one of the reasons the United Nations Educational, Scientific and Cultural Organization (UNESCO) declared the area a biosphere reserve in 2005.

The ferry makes its way around islands full of trees that hang toward the sea from cliffs or crawl toward the sand of small, deserted beaches. Unlike the previous day, there are white cotton-like clouds in the sky; others are gray and even black. Still, the light has a special clarity, as if it were brighter than usual, as if a veil had been lifted, distinguishing the different whites of the glaciers that stretch out like tongues of ice from the tops of the mountains until they meet the sea. At their tops, the glaciers are the color of snow, becoming light blue, emerald or transparent as they approach the water.

“I don’t want to take any more photos. I feel like it’s distracting me,” says a tourist absorbed in the landscape. An exclamation of surprise interrupts the calm when a whale sprays a jet of water out of the sea. There are four or five whales swimming together, showing their backs on the surface of the water.

For hours the ferry skirts Alberto de Agostini National Park, one of three national parks within the Cape Horn Biosphere Reserve. We leave it behind and enter Yendegaia National Park before sailing through the Beagle Channel and passing Ushuaia in Argentine territory. The ferry continues farther south. The day ends, the sky darkens again and, without leaving the biosphere reserve, we approach our final destination on Navarino Island: the Cape Horn International Center for Global Change Studies and Biocultural Conservation (CHIC).

There, experts in insects, birds, plants and the climate are carrying out scientific research to understand how climate change is impacting the various inhabitants of these subantarctic forests.

Since Ricardo Rozzi, CHIC’s co-founder, began frequenting Navarino Island in October 1999, “the changes in the landscape are dramatic,” he says. “We used to have herds of guanaco. There were icebergs above, in the lagoons of Omora Ethnobotanical Park. Now we don’t have icebergs, and we hardly have any guanacos. There were thousands of geese. It was a marvel; geese, geese and more geese would fly over. We never went out in a T-shirt, we always wore a parka, winter and summer.”

Understanding these variations and observing how different species are surviving or suffering from them will enable humanity to anticipate what is to come in the future, and to devise ways to deal with the changes.

It’s 12 at night and we can see, hanging off the end of the continent, the little lights of Puerto Williams.

The world’s southernmost forests

To understand the importance of these temperate forests and how they are changing, it is necessary to understand what they are and how they work.

The day begins in Omora Ethnobotanical Park, a public-private protected area located just 4 kilometers (2.5 miles) from the city. The park conserves the Róbalo River watershed, which supplies both Puerto Williams and 1,000 hectares (2,471 acres) of the southernmost temperate forest in the entire hemisphere. A family of woodpeckers peck the trunks of some trees. There’s a male with a red head, a juvenile with a red mohawk and a female that takes flight, displaying her black-and-white barred plumage.

Only six tree species make up these subantarctic forests, which are considered one of the most pristine ecosystems on the planet: lenga beech (Nothofagus pumilio), Antarctic beech (N. antarctica), Magellan’s beech (N. betuloides), winter’s bark (Drimys winteri), Chilean firebush (Embothrium coccineum) and Magellan’s mayten (Maytenus magellanica). In terms of geological time scales, these forests are relatively young, having only begun to form after the last ice age ended about 20,000 years ago. As a result, they are still in the stage of creating conditions for other types of species to grow.

We see some of these trees lying horizontal on the ground, uprooted by the wind. Surprisingly, instead of their roots growing vertically down into the earth as an anchor, they extend horizontally, almost superficially above ground. Why would a tree prefer to grow like this and risk being uprooted by a stiff wind? The reason is linked to the short amount of time that has passed since the last ice age.

“When the ice retreated, what remained exposed was a completely bare rock face,” says Alex Waldspurger, a park ranger at Omora Ethnobotanical Park. The first forms of life that settled on this bare rock were mosses and lichens. By reproducing, dying and decaying, the mosses and lichens began to form the soil where, little by little, other types of plants started to grow. This is what scientists call ecological succession.

“If you make a hole in the earth … around a meter or a meter and a half [3-5 feet] down, you run into the bedrock. It’s very thin ground,” says Waldspurger, who is also a biologist. Because of that, tree roots cannot go very deep into the soil, as they do in the Amazon, for example, where the soil is much older. And because of that, the ranger says, “the trees in this type of forest fall a lot.”

The territory’s youth means that this region of Patagonia has a limited variety of trees, but an enormous diversity of mosses, which still dominate at this stage of ecological succession. In fact, the region has the greatest concentration of moss species in the world, according to Rozzi.

“It is a hotspot of biodiversity, but of moss biodiversity, and this justified, in part, the declaration of the Cape Horn Biosphere Reserve,” says Ramiro Bustamante, an ecologist at the University of Chile.

The soil formation process in these latitudes is particularly slow due to the low temperatures, which slow down the decomposition of organic matter. “The impressive number of tree trunks lying on the forest floor is evidence that decomposition rates are very slow compared with what happens in tropical ecosystems, where everything that falls decomposes quickly,” Bustamante says.

At this point, the mosses come back into play. It is they that permit the decomposition of fallen trees to accelerate and continue building the soil so it can support increasingly greater biodiversity.

But the function of the mosses is not limited to decomposition. They also provide these naturally poor soils with the nutrition necessary to feed other species. For example, Spanish moss (Tillandsia usneoides), known as old man’s beard in Spanish, grows on the trunks of the oldest trees and indeed resembles a pale green beard. It acts as a channel that permits the forest to nourish itself from the ocean: When the wind blows, droplets of seawater rich in nitrogen, phosphorus and salts are transported to the forest and retained by the moss. Then, when it rains, the water washes the tree trunks and the old man’s beard carries the nutrients into the soil. “That’s the level of subtlety of ecological functions, interactions and coevolution, where each [species] has its place and role,” Waldspurger says.

Cohabiting in a democracy of species

Omora Ethnobotanical Park was created as a space for tourism and outdoor education, and also as a natural laboratory. Scientists from CHIC, also known as the Cape Horn Subantarctic Center, use the park to carry out research, although their studies are not limited to this area.

Javier Rendoll, a CHIC biologist, studies insects along the Róbalo River, which flows from its headwaters in the Dientes de Navarino to its outlet in the sea. He spends hours lifting stones and sticks, observing the tiny beings that live in the water. He and his colleague, Tamara Contador, decided to study the insects in the field, rather than collecting them and taking them back to the laboratory. It’s a slower process, but it aligns with the methodology CHIC scientists agreed to apply, adhering to environmental ethics that consider living beings as subjects of study and not as objects of study.

The concept that prevails in Omora Ethnobotanical Park and that park rangers and scientists try to convey to visitors is that we human beings should try to understand ourselves as cohabitants, which means we share a habitat where, like the old man’s beard, all living beings have a function in a perfect machine.

“A lichen forms the soil that allows trees to grow, which give us oxygen. By understanding that, we assume an ethical responsibility for care, because we want the trees to do well so that they can do well for us,” Rozzi says. In that sense, he adds, “It’s a democracy of species, in which lichens, mosses, birds, insects, trees and humans all have the right to live.”

In two reports, an interview and a video, available in Spanish, Mongabay Latam details how high temperatures and the lack of rainfall resulting from climate change have affected subantarctic forests. The life cycles of certain insects have changed, normally flooded ecosystems are drying out and mosquitoes have arrived in the area, which could transmit tropical diseases like malaria to birds. This special series also recounts scientists’ efforts to understand the changes taking place and predict future impacts so we can adapt to a new climate.

Ultimately, this report tells the story of people who, from the edge of the world, are seeking to teach the value of life in all its forms.

 
Banner image: Navigating through the channels of Patagonia from Punta Arenas to Navarino Island, Chile. Image by Michelle Carrere for Mongabay.

This article was first published here in Spanish on Mongabay’s Latam website on May 17, 2023.