Biodiversity in the news, articles that stood out and caught my attention.
published 15 October 2017 | modified 15 October 2017
Pumas, long known as solitary carnivores, are more social than previously thought, according to a new study published on 11 October in the journal Science Advances. The findings provide the first evidence of complex social strategies in any solitary carnivore – and may have implications for multiple species, including other wild cats around the world.
“It’s the complete opposite of what we’ve been saying about pumas and solitary species for over 60 years,” said lead author and Panthera Puma Program lead scientist Mark Elbroch, Ph.D. “We were shocked – this research allows us to break down mythologies and question what we thought we knew.”
Usually termed 'solitary carnivores,' pumas (Puma concolor) have been assumed to avoid each other, except during mating, territorial encounters, or when raising young. The population of pumas that was studied interacted every 11-12 days during winter, which is very infrequently compared to more gregarious species like meerkats, African lions, or wolves, which interact as often as every few minutes. So to document social behaviour, Dr. Elbroch and his field research team had to follow pumas over longer time spans.
Using GPS technology and motion-triggered cameras in northwest Wyoming, the team collected thousands of locations from and documented the social interactions of pumas over 1,000 prey carcasses (242 with motion-triggered cameras that filmed interactions). Then, they used cutting-edge analyses of puma networks to reveal that the species exhibits social strategies like more social animals, just over longer timescales. The research is the first to quantify complex, enduring, and 'friendly' interactions of these secretive animals, revealing a rich puma society far more tolerant and social than previously thought.
Mark Lubell, co-author, director of the UC Davis Center for Environmental Policy and Behavior
1. Every puma participated in a 'network' of individuals sharing food with each other. Each puma co-fed with another puma at least once during the study, and many of them fed with other pumas many times.
2. Choosing individuals with whom to share meals was not random or reserved for family members. The pumas seemed to recall who shared food with them in the past – and were 7.7 times more likely to share with those individuals. This is usually only documented with social animals.
3. Males received more free meat than females, and males and females likely benefited differently from social interactions. Males got meat, while females likely received social investments facilitating mating opportunities.
4. Territorial males acted like governors of 'fiefdoms', structuring how all pumas across the landscape interacted with each other. All pumas living inside each male territory typically formed a single network, and were more likely to share their food with each other. Social interactions occurred across these borders, but much less frequently than among cats within the same male territory.
The study emphasizes that puma populations are actually composed of numerous smaller communities ruled by territorial males. The loss of males, whether by natural or human causes, potentially disrupts the entire social network.
Videos and images captured during the study served as 'irrefutable' evidence of social behaviour,said. "Suddenly, I was able to see what was happening when these animals were coming together. By stepping back, we captured the patterns of behaviour that have no doubt been occurring among pumas all along."
Except for lions and cheetahs (whose males form long-term social groups), all wild cats are typically described as solitary – a strategy characteristic of species living in complex habitats where predators compete for dispersed prey. This study should encourage researchers to study the social behaviour of other solitary carnivores.
"This work goes against convention for solitary carnivores, but our evidence is supported by both behaviour and genetics," said co-author Anthony Caragiulo, Assistant Director of Genomic Operations at the Sackler Institute for Comparative Genomics at the American Museum of Natural History.
Dr. Elbroch stated, "This opens the door to enormous possibilities. Are pumas everywhere behaving the same, or only in areas with large prey? Are other species like leopards and wolverines and so many others acting the same way? There is so much more to discover about the rich, secret social lives of wild creatures."
(Source: Panthera press release, 11.10.2017)