Wild Pig Nesting
Piggy engineering and infrastructure
Nests are a fascinating way pigs shape their environment
Farrowing sows - those female pigs anticipating giving birth - will construct nests to give some form of protection to the new born. Nesting is a way of the pig temporarily shaping its habitat, often in response to the weather.
Regarding its broader effects beyond the species, nesting can be a form of ecosystem engineering that shapes the biological composition of an ecosystem. For example, since pigs destroy saplings to create nests in Malaysia they might be seen as competitors to trees. However, this paper also found that pig nesting can affect forest diversity and the eveness of plant species spread across a given area. A finding that adds more nuance to the dominant characterisation of the wild pig's effect on the environment as being largely detractive. It is unknown if similar effects might occur in ranges where the wild pig is considered invasive.
In Canada, where the temprature can get especially cold, free-living pigs reportedly build "pigloos", a porcine infrastructure that supposedly helps the pig expand their ranges into climatically hostile territory . Unfortunately, there are very few photos of such pigloos!