Varvara's Surprising Travels
New Discovery Made as Scientists
Track an Endangered Gray Whale
Who is Varvara?
She is a 9-year-old (in 2011) female gray whale on an unusual journey that helped scientists make a surprising new discovery about migration patterns. When scientists fired a small satellite tracking tag into Varvara's blubber off Russia's Sakhalin Island in September 2011, they expected to follow her along Asia's Pacific shoreline down to the South China Sea. To their surprise, she turned up off Mexico's Baja Peninsula instead.
She mingled with the eastern Pacific gray whales (the ones we track on Journey North) near their nursery lagoon sanctuaries in Mexico. Then she she turned north again. Her travels are shown on the maps below.
In April 2015, the data from the satellite tracking led researchers to announce that Varvara had broken the known world record for longest mammal migration. There's still more to discover. Read on to see how two gray whales nicknamed "Flex" and "Varvara" have changed scientists' understanding of gray whale migration patterns!
Mapping Varvara's Travels
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June 3-10, 2012 |
May 20-27, 2012 |
April 29-May 6, 2012 |
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April 22-29, 2012 |
April 15-22, 2012 |
April 8-Apr. 15, 2012 |
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Apr. 1-8, 2012 |
March 25-Apr. 1, 2012 |
March 18-25, 2012 |
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March 4-11, 2012 |
Feb. 26-March 4, 2012 |
February 5-12, 2012 |
Two Herds of Gray Whales
Gray whales once swam in both the Pacific and the North Atlantic Oceans. Whale hunting brought both herds near extinction. The eastern Pacific population recovered, thanks to a global ban on whaling. It was taken off the Endangered Species List in 1994. In the 1970s scientists believed the western gray whale was extinct, but a small group was discovered off Russia's Sakhalin Island. Since 1995 a joint Russia-U.S. research team, co-directed by NOAA scientists, has monitored these whales, located off the far-away coast
of
Russia
and
Japan. With only about 130, the western population is listed as endangered under the U.S. Endangered Species Act.
Until recently, scientists believed these two populations of gray whales never crossed paths. They believed Western Pacific gray whales
were a separate and genetically different population. The western herd didn't usually cross the Bering Sea; they migrated to breed in the south China Sea.
Flex and Varvara Change Scientists' Beliefs
The first evidence that western Pacific gray whales were migrating from Sakhalin Island in the Russian Far East, across the Bering Sea to North America came in 2010 when scientists tagged a 13-year-old male they dubbed Flex. His tag stopped transmitting just before he reached California.
Flex
was later identified in photos showing he had visited Tofino, BC, several years earlier. Now Varvara's journey has solidified the pattern set by Flex: She swam down to the eastern gray breeding and calving lagoons of Baja Mexico. She mingled there with her eastern cousins—the more abundant Pacific gray whales, which we track each spring on Journey North.
Data Surprises Scientists!
The travels of Flex and Varvara have clearly shown that western gray whales can and do come over the eastern Pacific. Scientists at Oregon State University’s Marine Mammal Institute at have begun to wonder if the western Pacific herd is indeed a distinct population after all. They also wonder if they underestimated the range of the small western Pacific herd.
"Among the many things Varvara and Flex have taught us is the potential for intermingling between the western and eastern gray whales—not only on the breeding grounds, but during migrations and spring feeding aggregations along the way," said Jim Darling, director of the Pacific Wildlife Foundation. Scientists are continuing to collect data in hopes of learning more.
The Plight of Western Pacific Gray Whales
With only 130 in the herd, many experts fear this population will go extinct. The western Pacific is a dangerous place to be a whale. Gas and oil explorations have moved into the western herd's feeding grounds. Some of the whales have been captured and drowned in Japanese fishing nets. Scientists wonder: Instead of facing doom, are these whales seeking new ways to survive? Scientists hoped to learn more by putting satellite tracking tags on some of the whales. They are learning surprising things!
Where Will Varvara Go Next Winter?
Bruce Mate is one of the five scientists that tagged the whales. He has watched Varvara's travels in amazement, saying, "This is the first time that we know any whales has visited all the major breeding areas, not to mention all in one season." Scientists will be watching to see if Varvara has a calf next year. If she does, they expect her to return to the Mexican calving lagoons to give birth. Thanks to photo ID, they know Varvara's individual markings. They will be watching to see if she returns.
Mystery to Solve
Tagging along with Flex and Varvara has painted a more detailed picture of gray whale migration. The last two Arctic winters (2009-10 and 2010-2011) have been so warm that the ice sheet that formed a barrier between Pacific and Atlantic waters retreated. What do all these changes mean for gray whales? Dr. Dave Weller and his long-time NOAA colleague Bob Brownell hope to find out. They seek permission to enter China, where they want to team up with their Chinese colleagues and fishers in order to find places along the Asian coast where gray whales spend their time. Stay tuned!
Credit: This research was conducted by A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) and Oregon State University Marine Mammal Institute in collaboration with the U.S. National Marine Fisheries Service, Kronotsky State Nature Biosphere Reserve and the Kamchatka Branch of the Pacific Institute of Geography. The research was contracted through the International Whaling Commission (IWC) and the International Union for Conservation of Nature (IUCN) with funding from Exxon Neftegas Ltd. and Sakhalin Energy Investment Company Ltd.
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