AAt the peak of the whaling industry in the late 1800s, North Atlantic right whales were slaughtered by the thousands. With every carcass carried on deck, the whalers were taking more than bones and flesh from the ocean. Killed whales had unique memories of feeding grounds, hunting techniques, and communication styles; knowledge acquired over centuries, transmitted from generation to generation and shared among peers. The critically endangered whale clings on, but much of the cultural knowledge of the species is now extinct.
Whales are among many animals known to be highly cultural, says Professor Hal Whitehead, a marine biologist at Dalhousie University. “Culture is what individuals learn from each other so that a group of individuals behaves the same way,” he says.
North Atlantic right whales are no longer found in many of their ancestral feeding grounds. Whitehead suspects this may be because cultural knowledge of these places was lost when populations were wiped out by whaling. This loss could cause problems for the species if human activity degrades its remaining feeding grounds, making it difficult for whales to predict where good hunting is. “The more possible feeding areas they have, the more likely they are to find a place where they can get the food they need,” he says.
Animal culture is not limited to the ocean. Birds, bees, naked mole rats, fish, and even fruit flies are among those who learn socially and create cultures. As the list grows, researchers are beginning to realize that animal culture is essential to many conservation efforts.
Whitehead was one of the first voices calling for animal culture to be taken seriously in conservation. Indeed, cultural diversity gives a species a greater behavioral toolbox in the face of new challenges, he argues. “We recognize that with humans, that the diversity of our cultures is a strength.”
Whitehead is a member of the Committee on the Status of Endangered Wildlife in Canada, a body that decides which species are endangered. “The hardest thing to do is decide how to divide a population of a species,” he says. In caribou, for example, plains caribou are doing better than mountain caribou. “Do we assess mountain caribou differently than others? Whitehead asks.
Typically, this decision is made by assessing how genetically different the groups are. “One of the things I’ve championed is the idea that cultural information is also important.”
Conservation efforts aim to maintain the diversity of a species, because diversity aids in survival. Species diversity can be “what it does, what it looks like, its physiology, etc,” says Whitehead. “Many [of the diversity] is genetically determined, but some of it is culturally determined.
The behaviors of a population can have a significant impact on the environment in which it lives. “If we lost all the mountain caribou, it could change the ecology of a group of mountain peaks,” says Whitehead.
Whitehead’s research into whale culture provided an illuminating moment for Whale and Dolphin Conservation researcher Philippa Brakes. Brakes, a PhD student at the University of Exeter, published a paper with colleagues in April, which argues that conservation efforts should consider how culture affects reproduction, dispersal and survival.
Understanding who holds cultural knowledge in a population can be key, says Brakes, who cites African elephant herds as an example. “The age of the matriarch in the herd matters [positive] influence on the fertility rate of young women,” she says. “The [matriarch] The female’s experience with the location of watering holes, good foraging and other friendly social units has a demonstrable ripple effect on the fertility rate of young females in her herd.
“If you remove individuals who have knowledge, through hunting for example, it can have a ripple effect much wider than just minus one of your population.”
However, when a population has lost its cultural knowledge, there may be circumstances where it can be revived.
If a human were taken from their home, stripped of everything they learned from others, and then fell back, they wouldn’t survive long without support. The same seems to be true for golden lion tamarins, a small monkey from Brazil.
By the early 1970s, habitat destruction and the pet trade had reduced the golden lion tamarin population to just 200 individuals. Captive breeding, overseen by 43 institutions in eight countries, increased their numbers to the point that conservationists were able to reintroduce tamarins into the wild beginning in 1984. But initially reintroduced tamarins had a low survival rates, with problems adapting to the new environment responsible for the majority of losses. High losses are typical of such efforts, Brakes says.
The tamarind researchers therefore developed an intensive post-release program, including supplemental feeding and the provision of nesting sites, giving the monkeys time to learn necessary survival skills for the jungle. This helping hand doubled survival rates, which was a good start. However, it was not until the next generation that the species began to thrive. “By giving them the opportunity to learn individually in the wild and share that knowledge, the next generation of tamarins had a 70% survival rate, which is just amazing,” says Brakes. Intensive conservation efforts have paid off, and in 2003 the golden lion tamarin was downlisted from “critically endangered” to “endangered”.
While this research is promising, animal cultures go out faster than they come back on, Brakes says.
“We’re just beginning to understand what culture is in other species, and we’re just beginning to develop ways to measure and analyze culture, because we’re seeing it disappear before our very eyes.”