From this tiny island, they've watched the sea for 60 years. Here's what they've learned.

Researchers on Helgoland in Germany have observed temperature and sea life at the same spot offshore every workday since 1962. The data are a unique document of climate change.

By Florian Sturm
photographs by Esther Horvath
Published 25 Sept 2021, 06:11 BST
Helgoland, population 1,370, lies 30 miles off the German mainland in the North Sea. A popular tourist spot, it's so small that cars are banned and bicycles heavily restricted.
Photograph by Esther Horvath

Sure, he could use the little screen mounted on the teak panel in front of him to check his position. But Dieter Klings doesn’t need GPS. The 59-year-old captain of the Aade, a research vessel operated by the marine lab on the tiny German island of Helgoland, simply looks over his left shoulder and waits. The slow rumble of the engine drowns out the skree of circling seagulls and gentle splashing of waves against the wooden hull. With barely any wind today, the boat floats peacefully in the North Sea.

“Once you see the big staircase, you steer to the right and go just a little further until the top of the church and the lighthouse perfectly align. Then you know you’re there,” Kling says. I secretly glance at the GPS: 54° 11.180’N, 7° 54.000‘E. Exactly where we need to be.

Klings has been going to this very spot off the coast of Helgoland, about 30 miles from the German mainland, every working day for 38 years. Each time, he and his two crew members, sailor Kai Siemens, 58, and helmsman Ove Breiholz, 55, follow the same routine. They collect water samples and measure the sea temperature and transparency. They lower giant, funnel-shaped nets into the ocean and tow them behind the boat. The nets fill with all types of plankton—the single-cell plants called phytoplankton, tiny animals like copepods, and sometimes jellyfish.

A conical net collects plankton as it is towed by the Aade, a boat operated by the Biologische Anstalt Helgoland (BAH)—the island's 129-year-old marine lab.
Photograph by Esther Horvath
Dieter Klings has captained the Aade for the past 38 years, piloting it to the same spots in the sea every work day to collect plankton and seawater.
Photograph by Esther Horvath
The Aade, tied up at the dock on Helgoland.
Photograph by Esther Horvath
During a 30-minute plankton tow, crew members Kai Siemens (left) and Ove Breiholz (right) relax in the cabin.
Photograph by Esther Horvath

The plankton net was invented on Helgoland in the 1840s by German biologist Johannes Peter Müller. The Biologische Anstalt Helgoland (BAH) was established in 1892, making it one of the oldest marine research stations in the world.

And since 1962, researchers there have maintained what is now the longest running and most detailed series of measurements on the physical and biological state of one point in the ocean. The Helgoland Roads time series, as it’s called—the spot Klings visits every day is in the channel between Helgoland and a neighbouring island—provides a unique look at how this part of the North Sea is changing.

“This data series is a treasure. I’m not exaggerating,” says Karen Wiltshire, 59, director of the BAH. The measurements have become a scientific goldmine. Some of the results illustrate climate change writ large: They show that the waters around Helgoland have risen by 1.9°C since 1962 (3.4°F) —about double the global ocean average.

"The most desolate place"

Growing up in Dublin, Ireland, Wiltshire wanted to become a forester or an Arctic researcher. But she was denied both of those careers, she says, because of her gender. Opting for marine science instead, she did her Ph.D. at the University of Hamburg in the 1990s, sampling plankton and nutrients in the area known as the German Bight. That’s when she spent her first night on Helgoland.

“This seems like the most desolate place on the planet,” she recalls thinking when she saw the treeless expanse of red sandstone rising in 200-foot-high cliffs from the sea. “How can anyone live here?”

A few years later, in 2001, she got a chance to find out: She moved to Helgoland to become director of the BAH. She stayed there in 2006 when she took on added responsibilities as a vice director of the Alfred Wegener Institute, a large polar research centre in Bremerhaven that operates the BAH. In 2014 she finally moved to Sylt, another North Sea island, to run another BAH facility—but she still runs the Helgoland lab too.

Kristine Carstens technical assistant of Biological Institute Helgoland (BAH) of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research filters and measures the nutritions (silicate, fosfat, nitrit, nitrate, ammonium) in the seawater collected every day by AADE research boat.
Photograph by Esther Horvath
The Helgoland lab also collects animals such as squid (left) and spider crabs (right). They will be studied by scientists at its parent organization, the Alfred Wegener Institute in Bremen.
Photograph by Esther Horvath

She’s attached to the place, and not just because it’s an atmospheric, car-free world apart, beloved both by tourists and its 1,370 permanent residents. Helgoland, she says, connects her directly to her scientific roots in the 19th century, when the great German biologist Ernst Haeckel was coming here to net plankton, and he and Charles Darwin were inspiring biologists to discover the sea, as the place where life began.

“If you can identify with those who've gone before you, like Darwin and Haeckel and the people who developed the first plankton nets, then you're part of it,” Wiltshire says. “It’s like a big team that's been there for a long time, passing on the information. It gave me a sense of purpose, of hold, a position in history even—especially as a woman.”

It’s thanks to Wiltshire’s efforts that the Helgoland Roads project continues, and that its relevance now is acknowledged by marine scientists and policy experts alike. During her first months in office, Wiltshire took a closer look at the monitoring data and found something her colleagues had overlooked.

“The data clearly told me that the sea temperature around Helgoland was rising,” she says.

“Just counting stuff”

Her peers weren’t very interested at first. For many, human-caused global warming wasn’t yet firmly on the map; they suggested the temperature rise was probably just a natural climate cycle. And routine monitoring efforts like the Helgoland time series have always struggled for scientific respect. “Monitoring isn’t science, it’s just counting stuff,” Wiltshire recalls her peers saying.

But Wiltshire knew she was on to something—and fought time and again for the monitoring to continue. She embedded the data in the science of her colleagues. She created small projects based on the numbers as well as entire research programs investigating the complexities of marine food webs.

The beam from the Helgoland lighthouse is visible for nearly 30 miles. A former anti-aircraft tower, it survived a British bombing raid in World War II that destroyed the previous lighthouse.
Photograph by Esther Horvath

Some of the findings, Wiltshire says with matter-of-fact pride, “even rattled the fundaments of theoretical marine ecology.” Scientists had long known, for example, that in spring phytoplankton bloom in the ocean, just as plants do on land, growing and multiplying—but the Helgoland data revealed that the spring bloom might not happen if the winter has been too warm.

The steady discipline of “just counting stuff” is now recording wholesale changes to the North Sea ecosystem, and thanks to improved research techniques, Wiltshire and her colleagues can see new connections in the data. The spring blooms—when they come—are coming earlier. That’s affecting the animal plankton and larval fish that eat the microscopic plants. As the water warms, it’s becoming less suitable for cod, the North Sea staple—but other species like striped red mullet and seabass, which used to be around Helgoland only in summer, now stay for the winter. Jellyfish and comb jellies have become more plentiful too.

Where is this leading? What will live in the North Sea in 10 or 20 years? “Unfortunately, we don’t have all the answers yet,” says Wiltshire. But there’s a mine of data growing steadily: “Currently, we’re not anywhere near its full potential with analysing it.”

Hunters exterminated gray seals from the southern North Sea in the early 20th century, but after hunting was banned in the 1970s the species has recolonized the region, including Helgoland. Michael Janssen is a hunter with a mission to protect: Here he prepares to fence off an area of beach around a newborn pup and its mother.
Photograph by Esther Horvath
Star tunicates are colonial invertebrates that are used in medical research. Each star is only a fraction of an inch across.
Photograph by Esther Horvath
Eva-Maria Brodte, a scientist at the Alfred Wegener Institute, collects star tunicates on Helgoland.
Photograph by Esther Horvath
Lange Anna, a 154-foot-tall sandstone pillar on the northwest coast of Helgoland, is a symbol of the island.
Photograph by Esther Horvath

Data by the bucket

Back on the boat, Klings and his crew start the second task of their daily trip. Each morning, the captain receives an order sheet from researchers on Helgoland with the animal or plankton species they want him to catch;  they’ll be sent on to universities and research institutes worldwide for study. Today, we’re after lancelets, eelpouts, brown crabs, comb jellies, and plankton.

Klings revs up the engine and the belly of the Aade growls a little louder. After a 15-minute cruise, we’ve reached the spot. Again, Klings doesn’t need the GPS. Within a radius of 16 nautical miles around Helgoland, he tells me, he knows exactly what to catch when and where.

“Is there a map for this?” I ask.

“It’s all up here,” Klings replies, tapping his right temple with his index finger. His crew are attaching a big plankton net to the ship’s crane.

Klings is probably the last person on Helgoland to spend his entire career on a boat. His family had been going to sea for generations when he was born on the island in 1961. For him, there was never any question: He dropped out of school at 14 to find a job on a fishing boat.

“When I came home from my first trip after six months, my mother asked, Boy, what have they done to you?” Klings recalls. He had returned as a man.

Soon, he started an apprenticeship as a fisherman and netmaker, and also learned how to captain. When he was ready to get his license, officials told him there was a problem: Under German maritime law, one has to be at least 23 years old to legally command a ship. Klings had passed all the exams at 21.

“They knew me well and also that I had much more experience than somebody my age normally did,” he says. “So they made an exception.”

Today Klings is only a few years away from retirement. He and “his old girl,” the Aade, have shared more than 100,000 nautical miles. His Nordic, weather-beaten face lights up with a proud smile as he tells me that.

His colleagues have finished reeling in the nets and funneling the plankton into large white buckets. Patches of white sand powder the oak deck. “We took some sediment samples yesterday,” says helmsman Ove Breiholz. The three men work almost entirely in silence. Whether it’s just concentration or second nature to people living in a place like Helgoland and working at sea, I can’t tell. Probably a bit of both.

After about 90 minutes, the research trip comes to an end. The nets are stowed, the samples ready for the scientists.

“For us, it’s only a few buckets of sea water every day,” Klings says, steering back to shore. “But for the people at the Alfred Wegener Institute, it might be a dissertation. Or, for a researcher at the other end of the world, the missing piece to a big ocean climate model.”

Esther Horvath is a Germany-based photographer who documents polar regions. Follow her on Instagram.

Florian Sturm is a freelance journalist in Germany who writes about science, travel, and other subjects—including islands. Follow him on Twitter.


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