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Antarctic Peninsula CNN  — 

About 15 billion miles from where you sit, two 12-inch golden records are hurtling through outer space with multilingual greetings to the universe from 55 humans and one humpback whale.

With a playlist curated by astronomer Carl Sagan and inspired by the way humpbacks use low frequencies to send messages across entire oceans, they were launched on NASA’s two Voyager probes in 1977.

“As much as the sounds of any baleen whale, it is a love song cast upon the vastness of the deep.” Sagan wrote of the golden records.

And, since 95% of the planet’s biggest species had been harpooned to oblivion at the time, it could’ve easily been the kind of love song that ends in tears.

But almost a half-century later, the comeback of the humpback is arguably the greatest success story in the history of conservation. While artificial intelligence could one day help us understand the lyrics of those songs in space, new science is putting a dollar value on the life of a whale — and finding they provide so much more than blubber and song.

“They’re literally seeding the upper parts of the ocean with the opportunity for plant life to grow,” veteran marine ecologist Ari Friedlaender explained while bobbing on a Zodiac raft off the Antarctic Peninsula. “And that’s what feeds the food for whales, birds, seals — everything. They’re basically farmers recycling nutrients and there’s more food available to them the more they’re around.”

CNN followed an international team of whale experts throughout 2023, from Friedlaender’s lab at the University of California at Santa Cruz to humpback breeding grounds off the Pacific coast of Colombia, and their feeding grounds at the bottom of the world. While Friedlaender has been collecting whale data for more than 25 years, his work found new relevance after a team of economists from the International Monetary Fund estimated a single baleen whale provides about $2 million worth of Earth services, both in life and death.

When baleen whales gulp vital nutrients like iron and nitrogen from the depths of the sea and defecate at the surface, they serve as the ocean’s biggest fertilizer pumps — feeding the tiny phytoplankton which produces half the world’s oxygen and captures as much planet-warming CO2 as four Amazon rainforests while holding up the bottom of the food chain.

“That’s the gold,” smiled Chris Johnson, the global lead of whale and dolphin conservation at the World Wildlife Fund, as he held up a whale stool sample jarred from the chilly Antarctic water.

“We have the poo. Repeat, we have humpback poo,” Eva Prendergast, the British polar scientist at the helm, radioed back to the Ocean Endeavor, the cruise ship serving as base.

The team interacted with dozens of whales over the course of four days in Antarctica. They used specialized camera drones to measure body size and suction-cupped tags slapped onto the animals’ backs with a long pole to record the way they move while capturing whale’s-eye-view video.

A team uses a crossbow with hollow-tip darts to collect biopsies from afar. WWF's Johnson said the whales are not harmed by this -- to the whales, the dart feels like "a mosquito bite."
The scientists use antennas to detect the VHF signal emitted by the suction cup tags once they fall off the whales naturally, usually within a day. Sometimes the tags can't be located, but they will continue to float and be retrieved by other teams once they arrive.

But the most useful tools were MacGyvered into existence back at the lab in Santa Cruz. For over a decade, Friedlaender’s team has been using crossbows with hollow-tipped darts to collect biopsy samples. It feels like “a mosquito bite” to the whales, Johnson said, but what they can test for is priceless: from stress hormones to toxins to — most importantly — pregnancy rates.

“What else tells you how a population is growing or shrinking?” Friedlaender said after darting a humpback with a 20-yard shot and securing the tip in a sterile bag. “We can now tell if that whale is pregnant or not.”

He has over 2,500 samples from the same region back in a fridge at UC Santa Cruz, a data set that allows him to compare fertility rates with year-by-year changes in the environment. And as global warming melts sea ice at staggering rates, the habitat for krill is shrinking and humpback pregnancies are dropping.

“In the first year of life, juvenile krill spend the winter under the sea ice and feed on the microbial and algal communities,” Friedlaender explained. “We have a very good understanding that when you have a poor sea ice year, the following year you’re going to have lower reproductive rates. In good ice years, the reproductive rates are very high.”

Since the last two years have been the lowest levels of sea ice on record around Antarctica, the correlation is worrying, and the trend is only expected to accelerate as the planet warms.

21st century threats

But the climate crisis is just one tragic setback in the humpback’s comeback. While on the longest migration routes of any animal, whales must dodge cargo ships on crowded coastlines, “ghost” fishing gear cut loose at sea and floating clouds of plastic pollution.

And because of a global market for omega-3 krill oil supplements and nutraceutical feed for pets and fish farms, whales now compete with humans for their main source of food.

Industrial krill fishing fleets are taking to the Southern Ocean in growing numbers and have been recorded dragging their nets into areas full of feeding whales. After years of challenging whalers, the activist group Sea Shepherd will spend this season tracking krill fishers.

The fishery operation “puts additional pressure on krill and krill predators that, along with growing bycatch of non-target species like the humpback and a lack of transparency across the industry, suggest that the current management framework is outdated and needs to change now,” the WWF’s Johnson told CNN.

Early in a career devoted to marine mammals, Johnson spent five years sailing on the research vessel of Roger and Katy Payne, the married scientists who blew humanity’s minds by releasing Songs of the Humpback Whale in 1970.

A Sea Shepherd Global communication officer works on the bridge of the Allankay in the Southern Ocean on the night of March 3, 2023. The conservation group operates the Dutch-flagged vessel.
The Norwegian Aker BioMarine's Antarctic Sea trawls for krill in the Southern Ocean off the coast of the South Orkney Islands, north of the Antarctic Peninsula, on March 10, 2023.

While people were familiar with the echolocating clicks of dolphins and orcas, the first baleen whale noises were recorded by Navy engineer Frank Watlington by accident in the 1950s, and after the Paynes worked with fellow cetologist Scott McVay to record more humpback songs around Bermuda, they were played during marine mammal protection hearings in Congress and the United Nations. Ten million copies were inserted into National Geographic magazine in 1979 — the largest single pressing in history — and a global movement to Save The Whales grew big enough to … save the whales.

By 1986, the International Whaling Commission had instituted a global ban on all commercial whaling. While Japan, Norway and Iceland have continued regardless, years of lawsuits and international pressure forced Japan to lower its annual quota of Minke whales from 1,000 to 333, and the two boats of Kristján Loftsson, Iceland’s last whaler, harpooned two dozen fin whales in 2023.

But while the commercial harpoon is critically endangered, other threats remain — especially to whales that aren’t as supremely adaptable as the humpback.

Scientists believe there are only about 360 North Atlantic right whales left on Earth — a species named by whalers who pointed out the “right ones” to hunt. Entanglements with fishing and lobster gear are the main hazard for the species migrating from the Arctic down the Atlantic coast. But concern over the North Atlantic right whale, and a number of other species, found dead on American beaches has galvanized an unusual coalition of environmentalists, fishermen and Republican beach town mayors hoping to stop the development of offshore wind farms.

On a campaign stop in South Carolina, former President Donald Trump mocked a call for ship speed limits during whale migration season while blaming the nascent wind industry for the harm. “Windmills are causing whales to die in numbers never seen before,” Trump said, with no evidence to support the claim.

People work around the carcass of a dead whale in Lido Beach, New York, on January 31, 2023.