By Dr. Becker
Whales travel extraordinary distances during migration. While most large whales do migrate for feeding and breeding purposes, the paths they take and the distances travelled vary by species.
Baleen whales, which are those with baleen plates in their mouths that filter food like krill, travel to areas with cold water to feed (as krill is plentiful in cold waters) and then travel to warmer waters to breed and give birth.
It was thought that humpback whales were the longest-migrating mammal, as they travel up to 10,190 miles round trip from the cold waters near Antarctica to the warm, tropical waters of the Pacific. New research, however, found that gray whales have actually broken this migration record by travelling more than 3,000 miles farther!
Gray Whales Now Hold the Record for the World’s Longest Migration
Thanks to satellite-monitoring tags that researchers attached on seven western gray whales living near Sakhalin Island in Russia, the extensive migratory route of these majestic animals has been revealed.1 It was thought such whales migrated from Russia to the South China Sea, but the tags showed otherwise.
Only one tag survived the entire journey; a tag placed on a female western gray whale named Vavara. She travelled from Russia to Mexico… and back to Russia… logging in 13,988 miles in 172 days. The study's lead researcher, Bruce Mate, the director of the Marine Mammal Institute at Oregon State University, told Live Science:2
"She crossed the Bering Sea, the Gulf of Alaska [and] the lengths of the North American continent to get down to the Baja breeding calf lagoons that are used by eastern North Pacific animals.”
Even more striking, Vavara took a slightly different route on her way to Mexico as she did returning home to Russia. She didn’t need to stay near the coast for orientation, which suggests she had a pretty good feel for where she was headed. Mate continued:3
"My respect for navigational skills in gray whales has changed tremendously.”
Also noteworthy, the whales did not stop for a feeding during their 5.5-month migration.
Are Western Gray Whales Really Eastern Gray Whales?
The study raised another intriguing question, and that is whether or not western gray whales are actually eastern gray whales. Western gray whales are a critically endangered species while eastern gray whales are not.
Eastern gray whales also frequent the Mexican waters where Vavara migrated to, and there is speculation that the two whale species may be one and the same. The researchers noted their data “strongly suggests that some presumed WGWs [western gray whales] are actually EGWs [eastern gray whales] foraging in areas historically attributed to WGWs. According to Live Science:4
“It's entirely possible that Vavara and the six other whales that Mate and his team tracked are actually eastern gray whales that had migrated westward all the way to Russia… It's also possible what researchers have thought of as two whale groups, western and eastern, are actually a single whale species…
Evidence from photographs of whales taken by whale researchers also suggests they are just one group. For example, 10 western gray whales spotted in Russia have been photographed near British Columbia and Baja California, Mexico, the researchers said in the study.”
Dolphins Are Actually Whales and Other Whale Fun Facts
The name “whale” actually identifies several different types of marine mammals, including whales, dolphins, and porpoises. All are known as cetaceans, but dolphins and porpoises belong to the toothed whale group while gray whales belong to the baleen whale group. Want to know more?
- Baleen whales are known as the “great whales,” and they are generally much larger and slower than toothed whales. Sadly, seven of the 13 great whale species are classified as endangered or vulnerable, despite many years of protections.5
- As mammals, whales breathe air, are warm-blooded, and feed their young milk. They even have a bit of hair! Whales communicate using lyrical sounds that can be heard for many miles. They also use body language to communicate. For instance, a tail slapping the water’s surface is thought to be a warning of impending danger.6
- A female whale swims continuously for the first several weeks of her newborn’s life. Her swimming tows along the calf; if she stops, the newborn will sink, as it doesn’t have thick blubber or enough body fat to keep it afloat.7
- While the western gray whale now holds the record for longest migration, the blue whale still holds the title as the largest. These animals can grow to lengths of more than 100 feet and 200 tons, which is equivalent to 33 elephants!8