What creature has a nose like a bloodhound, locks or releases carbon into the soil based on where it lives, and was caught on camera freeing one of its own from a trap?
The wild boar! (Sus scrofa)

This week, Bio4Climate intern Eleanor Downey, a student at Bennington College in Vermont, takes us on a deeper dive to meet the ancestors of a creature she’s been fascinated with since she was little. Her love of pigs led her to investigate the wild boar and its relationship to the ecosystems where it lives.
Smart, Social, and Sympathetic
Wild boars live in sounders, tight-knit groups that are built around a sow and her litter. The adult males are usually solitary, except during breeding seasons. As nocturnal creatures, scientists have had a harder time studying them in the wild, but what they have learned is pretty cool!
In 2021, researchers recorded what is probably the first documented case of same-species rescue behavior by a wild boar. An adult female worked the wooden locking mechanism of a cage trap to free two juveniles caught inside. This kind of rescue behavior has only been documented in a few species. The female reportedly showed signs of distress while she worked, which has researchers wondering if empathy was part of what drove her.
Boars communicate through vocalizations, body gestures, and snout nudges. They learn quickly and have adapted to living near humans by shifting their schedules to avoid them, settling into smaller territories, and not reacting to nearby disturbances.
Powerful Sense of Smell
The wild boar’s nose is built for detection. It carries a number of olfactory receptor genes, traits that haven’t been bred out even in their domesticated pig descendants. Boars depend on their strong sense of smell for almost everything they do, whether it’s finding food, recognizing family members, or sensing potential mates. It’s also what makes them so good at finding truffles buried up to three feet underground, fungi that no other creature except a few dog breeds can find. Because the truffles are buried at that depth, boars are an important way that their spores travel through a forest at all, carried off in droppings after a good night of foraging.

The Dirt on Wild Boars
In their native habitat across Europe and Asia, wild boars shape grasslands like bison. As they root in the ground for food, they disturb topsoil, aerate it, and open up microhabitats where new seeds can take hold.
Their rooting impacts carbon in the soil, but in different ways depending on whether they’re in their native ranges or not. As they dig, boars mix organic matter from the forest floor with the mineral soil underneath. One 2021 study found this activity functions to redistribute carbon within the soil instead of releasing it, making the buried carbon more stable over time. Another study showed that boars living and rooting outside their native ranges disturb tens of thousands of square kilometers of soil and release millions of metric tonnes of CO2 a year. Regardless of location, it is clear that wild boars intentionally mix forest soils at scale. If it happens in their native landscapes, the soil has evolved to benefit from the disturbance. In other places, the impact is very different.
Are Boars an Invasive Species or Not? It Depends
Outside their native area, wild boars can cause problems. They have big appetites and their numbers grow quickly, making them invasive in a lot of places they’ve expanded to. One study using trail camera surveys found 26 percent less biodiversity in areas with wild boars than in areas without them. They eat just about anything that fits in their mouths. Add that to all the digging they do, and they can cause real damage. They can reshape wetlands, changing the natural topography, damaging flood plains, and altering how water flows and pools.
One of the most interesting outcomes of my exploration into boars is that the same traits that make wild boars important for climate resilience in their native habitats make them destructive elsewhere. The same animals showing the same behaviors have a completely different climate impact depending upon where they live.

Ellie Downey is a college student studying Literature and visual arts at Bennington College. She has worked primarily in the visual art sphere in the past, and is currently interning with a nearby city’s Public Arts and Culture department. In working with Biodiversity for a Liveable Climate writing Featured Creature articles, Ellie endeavours to combine her lifelong love of animals with her interest in writing.
Sources
- Masilkova, M., Ježek, M., Silovský, V., Faltusová, M., Rohla, J., Kušta, T., & Burda, H. “Observation of rescue behaviour in wild boar (Sus scrofa).” Scientific Reports, 11, 16217 (2021)
- Allwin, B., Swaminathan, R., Mohanraj, A., Suhas, G. N., Vedaminckam, S., & Kumar, M. “The Wild Pig (Sus scrofa) Behavior – A Retrospective Study.” Journal of Veterinary Science & Technology 7:333 (2016)
- “Wild boar in the city: Phenotypic responses to urbanisation.” Science of the Total Environment (2021)
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- “Wild Boar Proves High Tolerance to Human-Caused Disruptions: Management Implications in African Swine Fever Outbreaks” (2024)
- Groenen, M. A. M., et al. “Analyses of pig genomes provide insight into porcine demography and evolution.” Nature, 491 (2012)
- Piattoni, F., et al. “Interrelationships between wild boars (Sus scrofa) and truffles.” True Truffle (Tuber spp.) in the World: Soil Ecology, Systematics and Biochemistry. Cham: Springer International Publishing (2016)
- “Mycophagy by invasive wild boar (Sus scrofa) facilitates dispersal of native and introduced mycorrhizal fungi in Patagonia, Argentina.” Fungal Ecology, 26, 51–58 (2017)
- Don, A., Hagen, C., Grüneberg, E., & Vos, C. “Bioturbation by wild boar increases the stability of forest soil carbon.” Biogeosciences, 16, 4145–4155 (2019)
- O’Bryan, C. J., Patton, N. R., Hone, J., Lewis, J. S., Berdejo-Espinola, V., Risch, D. R., Holden, M. H., & McDonald-Madden, E. “Unrecognized threat to global soil carbon by a widespread invasive species.” Global Change Biology, 27(14), 3195–3196 (2021)
- Grunwald, S., et al. “Wild boar (Sus scrofa) has minor effects on soil nutrient and carbon dynamics” (2023)
- Ivey, M. R., Colvin, M., Strickland, B. K., & Lashley, M. A. “Reduced vertebrate diversity independent of spatial scale following feral swine invasions.” Ecology and Evolution (2019)
- Risch, D. R., Ringma, J., & Price, M. R. “The global impact of wild pigs (Sus scrofa) on terrestrial biodiversity.” Scientific Reports, 11(1) (2021)
















































