The social and cultural lives of belugas
Exploring beluga sociality and culture through the lens of behaviourial and evolutionary ecology.
Social behaviour is fascinating. Observing how animals relate, learn from one another, and care for each other always triggers my scientific curiosity. Whether watching dogs play, crows cooperate to solve problems, or starlings form breath-taking murmurations, I always want to learn more, to understand better. Whales in particular have some interesting and very diverse social habits.
With regard to social behaviour, some whale species have been relatively well characterized. Belugas are not among them.
Much of our historical knowledge of beluga social behaviour comes from comments and anecdotes buried within works focused on other topics. More recent research deepened the mystery, suggesting a complex sort of sociality that defied simple categorization. More puzzling, some findings appeared to be contradictory, hinting at something undeniably enigmatic. What was going on here? Did these contradictions reflect previous assumptions or methodological differences? Or maybe there were population-level or seasonal differences obscuring broader trends?
This curiosity was the impetus for our recently published review in Behavioral Ecology & Sociobiology. In this review, we explore several features of beluga sociality through the lens of behavioural and evolutionary ecology, including male and female social behaviour, multilevel social structure, menopause, and culture.
Menopause, fission-fusion dynamics, and male friendships
Like humans, belugas undergo menopause, such that female belugas often live for several decades after they stop reproducing. This life history trait is extremely rare in the animal kingdom and, on its face, seems to defy conventional evolutionary wisdom. After all, why stop reproducing early if spreading your genes is the name of the game?
In some cases, menopause does seem like a viable strategy. Resident killer whales live in stable matrilineal groups, where post-reproductive grandmothers provide guidance and ecological wisdom to their offspring and grand-offspring. Maybe, in such groups, it makes sense for older females to stop reproducing to focus on caring for their families and avoid competing with their daughters.
However, menopause also occurs in species with more fluid social structures, such as belugas.
Our review confirmed that beluga sociality is dominated by something called “fission-fusion dynamics”. Simply put, this means that groups tend to be ephemeral, merging and splitting periodically, structured more by individual relationships than by one uniting group identity.
In some ways, this is similar to human social behaviour. We move about the world, interacting with family, friends, co-workers, acquaintances, and strangers. Female belugas associate in similar ways, spending time with close relatives, but also with distant relatives and unrelated animals.
We suggest that belugas are matrifocal rather than matrilineal, meaning that relationships with maternal kin, while important, are not a defining social feature. The evolution of menopause in such societies suggests that older females play important roles within their groups, even when group structure is relatively unstable.
Male belugas are no less complex. Some researchers report that male belugas sometimes travel together for several weeks or months at a time, which could reflect the presence of stronger, more stable bonds.
These males usually aren’t relatives, suggesting that males choose their friends based on factors other than genetics. It is not yet known whether these bonds rival those seen among bottlenose dolphins, where males sometimes form life-long partnerships.
Cultural identities of belugas
Like humans, belugas also possess unique cultural identities.
During the summer, belugas travel to warm, shallow estuaries to give birth and care for their young. Knowledge holders inform us that some of these estuaries have been visited by belugas for several hundred years. But not just any estuary will do!
Our review suggests that the use of specific estuaries reflects a form of culture known as migratory culture. Dependent calves go through several migrations with their mothers before they reach adulthood, allowing them to learn the correct migration route and return to the same warm and familiar waters of their natal estuary year after year.
Belugas may also possess dialects, a form of vocal culture.
Among animals, dialects arise when animals learn their vocalizations from other group members. This results in vocal repertoires or “accents” that reflect where an animal is from or which group it belongs to.1
Belugas are prolific vocal learners, and given their social structure, it seems likely that belugas in different social groups might sound different from each other. More work is needed to determine whether belugas summering in different estuaries possess distinct dialects.
Conservation implications
Social behaviour and culture have profound implications for conservation. Belugas face many threats related to climate change, environmental contamination, and human-caused disturbance, and many Canadian beluga populations are currently at-risk.
By deepening our understanding of beluga social behaviour, we can better understand important factors such as disease transmission and exposure to noise and contaminants. By studying animal culture, we can also better assess how resilient different populations are when faced with ecological disruptions and other threats.To learn more about beluga social behaviour and culture, check out our recent publication in Behavioral Ecology and Sociobiology, and stay tuned for future updates from our research team!
