An adult gray whale cruises off the coast of Baja California. Every winter, gray whales travel from their feeding grounds in Alaska to the tranquil estuaries of Mexico's Pacific coast. Gray whale populations have fallen by a quarter in recent years, and the cause of death is unknown. In Baja California, gray whales arrived later than in the past and appear to have lost a lot of weight. Photo by MEGHAN DHALIWAL
Written by: KATE LINTHICUM
Off the coast of Baja California, as the morning fog clears, Alushe Camacho steers a small fishing boat through the mouth of a mangrove river. He stared at the horizon. For most of the year, Camacho catches grouper, flounder and hammerhead sharks. Today, his goal is to look for gray whales.
A few minutes later, Camacho spotted the target: a heart-shaped wave gushing out of the water. Suddenly, an adult cetacean sticks its head out of the water, stays for 5 seconds, and then disappears under the waves.
For decades, many tourists have come to this swampy region of Mexico to meet cetaceans, and thousands of gray whales come here from the Alaska Arctic every winter. Adult gray whales mate here, and females give birth in large serene lagoons and raise their baby whales.
Cammacho, 33, has been a tour guide for decades, and he'll nickname the whales that come back each season: Lucrecio slaps the boat with his tail, and Olivia gently pushes the baby whale, letting the amazed tourists caress it.
But over the past 3 years, Camacho and others have noticed that things are not going well. The whales arrived late, and many looked malnourished, with bumpy spines already visible on their usually plump backs. More cetaceans than ever before are being washed ashore and dying.
On the pier of the port of Adolf López Mateos, tourists gather around sculptures of gray whales and cubs. This is a small fishing village in Mexico that relies economically on cetacean tourism. Photo by MEGHAN DHALIWAL
The most worrying thing is the significant decline in fertility. Usually in the early morning of Early February, Camacho would see several mothers and children; today, he only saw adult gray whales.
The changes observed in Mexico attest to a more pervasive phenomenon that attracted public attention in 2019 and 2020: on the Pacific coast of North America, the number of stranded gray whales rose sharply. NOAA declared it an "unusual death" and launched an investigation into the causes behind the incident.
From 2016 to 2020, the estimated number of gray whales fell by nearly a quarter, from about 27,000 to about 20,500. So far, the cause of the decline has been a mystery. Many early studies have pointed to climate change, which has led to a rapid warming of the Arctic Ocean and a possible decline in the quality and quantity of cetacean food sources. But scientists can't rule out other factors, including the gray whale population growing too fast and is now only self-correcting.
Experts along the coast are conducting urgent investigations, as these mammals, which migrate about 20,000 kilometers, are key indicators of ocean health. Gray whales are a robust, adaptable species. Their trouble means more serious problems, including foraging grounds on the ocean floor, an important part of the ocean's food web, where scientists know relatively little because it's hard to study.
"Obviously, they're sentinels that reflect what's happening in the North Pacific ecosystem," said Sue Moore, a research scientist at the University of Washington who is helping lead NOAA's investigative efforts.
In Mexico, the issue is particularly pressing because on peninsular Baja California, the economy of a series of villages depends on the arrival of gray whales every year.
"Something went wrong, but we don't know what happened," Camacho said, "and what do we do if the gray whale doesn't come back?" ”
Whale watching guide Alushe Camacho sits on the bucket on the right, and he has a good relationship with his family. The family profits greatly from local ecotourism, which is much higher than the income from commercial fishing. "It's all credit to the gray whales," Camacho said. Photo by MEGHAN DHALIWAL
A fisherman collects shrimp from a net. In April, gray whales begin their long migration, heading north, while most whale-watching guides return to catch shrimp, lobsters, shellfish, sharks and manta rays. Photo by MEGHAN DHALIWAL
On the construction site of the port of Adolf López Mateos, a large number of fishing nets are piled together. Photo by MEGHAN DHALIWAL
Camacho spent his life in port Adolf López Mateos, a dusty town 5 hours north of Cabo San Lucas and home to 2,000 people. The shores of the shallow lagoon are also home to dolphins, egrets and pelicans, whose inhabitants are closely connected to nature. Ospreys nest at the top of electric poles, and coyotes sneak into dirty streets, waiting for fishermen to dock with their daily harvests.
But residents have a special respect for the gray whales. In front of the Catholic Church stands a sculpture of a gray whale, and the restaurant and elementary school are decorated with murals of gray whales. Locals say that because gray whales were born here, they belong to Mexico. Every winter, the village hosts a 3-day celebration to welcome the gray whale home, including concerts and beauty contests.
But that's not always the case.
In the 19th and early 20th centuries, foreign whalers gathered in these lagoons in search of blubber to make lamp oil. By the 18th century, whaling ships had already fished out a population of independent gray whales in the Atlantic Ocean. But with the establishment of the International Whaling Commission in the 1940s with the use of oil as fuel for lamp oil and the passage of the Marine Mammal Protection Act in 1972, grey whales were restored.
In the 1970s, foreigners came to the coast of Baja California again, this time not for whaling, but to admire. Eventually, the Mexican government set standards for sustainable ecotourism worldwide, stipulating that tours must be led by local tour guides, creating new jobs for former commercial fishing areas. Cetaceans react so friendly that they often look for boats on their own, inviting tourists to touch their heads or stroke their baleens.
From April to December, Camacho was a fisherman, earning an average of $170 a week; when the gray whale arrived, he became a tour guide for the Pilates Tour Company, earning six times as much as when he was fishing. His grandfather founded the company 40 years ago.
His brother made a dinner with the red snapper he caught yesterday, and he was also a whale watching guide. Camacho compared his recently acquired property to rustling palm trees on both sides, and he planned to convert a new building into a fish fillet company. "It's all credit to the gray whales," Camacho said.
In the clear waters of the lagoon, a female grey whale jumps out of the water. Newborn baby whales move downstream from the surface of the water. Cetaceans often bring their heads out of the water to stay alert. Photo by MEGHAN DHALIWAL
In the middle of port Adolf López Mateos, the façade of a hotel is painted with a mural of gray whales. Photo by MEGHAN DHALIWAL
Life jackets were hung behind a room in the town centre to dry. Most residents fish at sea or work in local sardine factories. Photo by MEGHAN DHALIWAL
Omar García Castañeda stood firmly at the bow of a bumpy motorboat, holding up binoculars with a safety rope wrapped around his waist. It's a stormy day, but time is precious: every year, gray whales roost in breeding grounds for about three months, and García and his colleagues have to count and photograph as many gray whales as possible.
They are marine biologists in laguna's San Ignacio Ecosystem Science Project. Since 2007, the team has been monitoring cetacean conditions off the coast of Baja California. Each year, the research team edits a catalogue of cetacean images, tracking individual activity, and identifying them through unique barnacles and scars. Importantly, these photos have also been used in recent years to assess the health of cetaceans.
The cetaceans are large, with a healthy gray whale weighing 40 tons and 15 meters long, making it difficult to tell if they are malnourished on deck. But nuances can be seen from the photos: is the cetacean's back thick and round, is there a depression behind the head, and is the shoulder blade protruding?
In the 10 years since the program began, the number of adult cetaceans considered ill-health has remained at around 6 percent. But in 2018, that percentage began to rise, rising to 30 percent in 2020.
Photographs taken by drones confirm this trend: between 2017 and 2020, more and more cetaceans are much thinner than they should be.
During the migration, the number of stranded cetaceans continues to set records. In 2019, 214 gray whales died, including 122 in the United States, four times the average number of deaths in the past 18 years. Scientists believe that for every time a cetacean is found dead on land, five cetaceans die in the sea.
Victor de la Toba Miranda and Marisel Valladolid in their backyard in port Adolf López Mateos. The couple goes to nearby beaches every week to look for animal carcasses that have washed ashore. Photo by MEGHAN DHALIWAL
Victor de la Toba Miranda shows us a photo of a young gray whale: in late December 2020, he found its body on a nearby beach. It's very thin and covered in lice. Photo by MEGHAN DHALIWAL
"We saw this phenomenon and couldn't do anything about it," said Steven Swartz, co-director of laguna's San Ignacio program.
Autopsies for cetaceans are particularly difficult because they are often washed up on remote beaches and decompose quickly. Typically, at the Marine Mammal Center in Sausalito, researchers perform autopsies on 1 to 3 gray whales, which generally do not enter San Francisco Bay during migration. But in 2018, the center tested 13.
Pádraig Duignan, the center's chief pathologist, speculated that the gray whales changed their usual route and entered the bay because they were hungry and looking for food. Autopsies showed that about half of the cetaceans were malnourished and that the fat reserves around organs such as the heart were very small. Once in the bay, they are particularly vulnerable to boat traffic: inspections found most of the cetaceans dying from hits by boats and ferries.
In the port of Adolf López Mateos, the spines of gray whales are on display. Photo by MEGHAN DHALIWAL
In Baja California, at the confluence of the Pacific Ocean and Magdalena Bay, outside Boca de Solleda, a gray whale has just dived underwater, and the surface of the water ripples. Photo by MEGHAN DHALIWAL
Victor de la Toba Miranda's backyard is piled with bones, mostly the backbone of gray whales. De la Toba, a resident of Adolf López Mateos Port and San Lazaro Island, counts the carcasses of animals washed up on the coast and reports what he sees to environmental groups. Photo by MEGHAN DHALIWAL
In 2020, 174 gray whales were washed up along the coast of a migration route. But the COVID-19 pandemic has limited researchers from conducting autopsies. The Marine Mammal Center has completed only one autopsy.
Duignan didn't know if the cetaceans died because of food shortages, disease, or pollution: their bodies were contaminated due to the ingestion of microplastics. But he said it was clear they were malnourished when they left the Arctic. "During the migration, there was not enough food 'along the way.'"
According to the hunger hypothesis, investigators turned their attention to alaska's Chukotka and Bering Seas; in the summer and autumn, cetaceans would prey on peduncles such as shrimp in large quantities to store blubber for eventual return to the south.
However, the Arctic Ocean is changing. Warming means less sea ice, disrupting the growth of seaweed, which is food for telopterans. Will shrinking ice sheets cause cetaceans to have fewer food sources?
The answer may be the simplest, but the situation was confused by the mass deaths of grey whale populations in 1999 and 2000, when the Arctic Ocean had a lot of sea ice. But just like now, gray whales ran aground and washed off the coast, and scientists report that gray whale populations fell 23 percent, from 21,000 in 1997 to 16,000 in 2000.
After that incident, the number of gray whales not only recovered, but also climbed all the way up, reaching as many as 27,000 in 2016.
Frances Gulland, who helped lead the NOAA team in investigating the first deaths, argues that climate change alone is not enough to explain two mass deaths 20 years apart.
"As far as we know, the Arctic is always changing, so why is there a 20-year gap between two mass deaths?" Marine mammal veterinarians say: "It must be food that is wrong, it's common sense, and we know that the Arctic has changed dramatically." But it's hard to say what the correlation between these changes is. ”
Others argue that this is simply because grey whale populations have reached some sort of carrying capacity and are self-correcting — a process that may now be being repeated.
Alushe Camacho watched as her 4-year-old daughter, Katharine, followed the two tourists up the sand dunes on Weir Chau Island. Camacho piloted the whale watching boat for them, and Katharine followed. "Whale watching season is like paid vacation," he said. For the rest of the year, he was a fisherman. Photo by MEGHAN DHALIWAL
In this photo taken by José de Jesús Flores González, tourists are touching a gray whale near a boat. Flores is a local who has been photographing gray whales since the 1990s. This photograph was taken in 2003 or 2004. Photo by MEGHAN DHALIWAL
Many people believe that this may be caused by a combination of factors.
"I think what we're seeing is the result of a series of events interacting," said John Calambokidis, a biologist at Cascadia Research Group and part of noAA's Abnormal Death Events Task Force. An increase in cetacean populations means increased competition for food. Add to that other factors that can lead to a reduction in prey, such as dramatic changes in the Arctic environment, hunger and death ensuing.
In recent years, more gray whales have shifted their migration routes and swam 160 kilometres away into Puget Sound, Washington State, in search of food; Calambokidis work here. The researchers say this means the whales are hungry, but it also means they're recovering. In just a few weeks, the cetaceans can gain weight dramatically, not by eating the end-footed animals on the ocean floor, but by eating at the ghost shrimp in the shallower parts of the bay.
Calambokidis hopes that gray whale populations will recover, as they did after commercial whaling and mass deaths in 1999 and 2000. "Gray whales may have adapted to it because they had to do that," he said.
The COVID-19 pandemic has brought tourism to a near standstill in port Adolf López Mateus, and the community has felt what life would be like without cetaceans. These days, the town's guides wait for visitors while listening to Kombia music on the modern pier. This year's Grey Whale Festival was canceled.
Fernando Rojas Rodriguez, 56, came here in 1990 in search of work. Through the cetacean business, he sent four children to school. Now, he worries about the gloomy outlook for tourism during the global pandemic, as well as the health of cetaceans.
Compared to the previous two years, we can't draw conclusions about how the whales will be stranded in 2021. Early reports submitted by scientists working in Baja California show that this season, there is a high proportion of emaciated cetaceans and very few female and juvenile whales.
But one recent morning, Rojas was lucky. A mother and daughter from Arizona came to town in a rented car to see the water.
Rojas drove his blue-green fishing boat slowly through the lagoon, herds of dolphins leaping out of the water in the distance, and pelicans paddling through the damp air. Then he saw a scene of a mist of water erupting from the water spray hole, with a smaller mist next to it.
Rojas turned off the engine. "It's a female whale and a juvenile whale," he said excitedly.
He estimated that the baby whale was about a week old and was already about the same length as a large sedan. Like a curious child, it rushed toward the boat, swam along the undulating hull, dived into the water, and reappeared on the other side of the hull. Rojas asks visitors to tap water with their hands. The baby whale swam closer, and in that instant, the daughter touched its smooth, blue-gray skin.
After a few minutes, the mother and baby whales left. The juveniles have to eat, and during these critical weeks, the mother whale has to raise it. In another month or so, they will embark on a difficult journey and head north. Rojas hopes they'll have a smooth ride and they'll be back later this year.
Three gray whales mate near Boca de Soleda. Females often mate with multiple males at the same time to increase their chances of getting pregnant. Photo by MEGHAN DHALIWAL
(Translator: Sky4)