New studies indicate that right whales can live for over 130 years, which is nearly double the duration previously believed.
New studies published in Science Advances indicate that right whales can live for over 130 years, almost double the duration previously believed.
Exceptional longevity is a characteristic shared with their relatives, the bowhead whales.
Researchers working alongside Indigenous whalers in Utqiaġvik utilized chemical analysis of bowhead whales caught in hunts to demonstrate that their lifespans can exceed 200 years. Supporting this chemical data, hunters have retrieved harpoon tips from the 19th century from bowheads taken in contemporary hunts.
Right whales, being closely connected to bowhead whales compared to other species, seem to show similar lifespan patterns. Like bowheads, right whales use baleen to filter feed and undertake seasonal migrations for birthing. Historically, whalers deemed them the “right” whales to hunt because their thick blubber made them buoyant after being killed.
This recent study involved examining four decades of data from photo-identification programs that monitored individual whales from two species: the Southern right whale, native to southern oceans, and the critically endangered North Atlantic right whale, found along North America’s Atlantic shoreline. The researchers created survivorship curves—graphs that depict the proportion of a population that survives at each age, akin to charts used by insurance companies for calculating human life expectancy.
The analysis discovered that Southern right whales, once estimated to live only 70 to 80 years, can actually live beyond 130 years, with some possibly reaching up to 150 years. Conversely, the North Atlantic right whale’s average lifespan is merely 22 years, with few surviving past 50.
Greg Breed, an associate professor at the University of Alaska Fairbanks and lead author of the study, explained that the significant disparity in lifespans between these closely related species is largely due to human influences.
“North Atlantic whales have notably shorter lifespans compared to other whale species, but this isn’t due to innate biological differences; they should live significantly longer,” he stated. “These whales often become entangled in fishing gear, collide with ships, and experience starvation, potentially related to environmental shifts that are not fully understood.”
Breed has dedicated years to studying marine mammals, including certain seal species that can live up to 50 years and narwhals, which can exceed a century. He pointed out that a shortage of data regarding whale aging had previously led to substantial underestimations of their lifespans.
“Prior to 1955, we lacked methods for aging baleen whales, which was around the close of industrial whaling,” Breed reflected. “By the time we developed those methods, few old whales remained for study, leading to the assumption that they did not live long.”
This research carries significant consequences for conservation strategies. “For populations to be healthy and include older animals, recovery may take hundreds of years,” Breed noted. “Given that these animals can live to be 100 or 150 and typically bear a surviving calf every decade or so, a slow recovery is expected.”
The study also highlights the significance of cultural knowledge within whale populations.
“There is an increasing acknowledgment that recovery encompasses more than just biomass or population numbers. It includes the knowledge that these animals share with their descendants,” Breed remarked.
“This knowledge isn’t solely genetic; it’s also cultural and behavioral. Older whales impart survival skills, while younger ones learn by observing and mimicking their elders’ strategies.”
The absence of older whales disrupts this essential knowledge transfer, ultimately affecting the survival of younger individuals.
Breed and his team plan to expand their research to investigate other whale populations and assess whether additional species currently estimated to have lifespans around 80 years may also typically live much longer. They aim to gain further insights into the impact of whaling on the number of older individuals in current whale populations and predict when those numbers might return to levels seen before whaling.