As we know, urban areas are expanding rapidly to accommodate the growing human population. However, this development comes at a cost to wildlife, as it significantly reduces their natural habitats. Urbanization can negatively impacts animals by forcing them to adapt to a rapidly changing environment. It also introduces challenges such as environmental pollution, as well as noise and light pollution, which cannot be overlooked. The loss of territory, prey availability, and hunting grounds often forces species to scavenge and forage in cities, far from their natural habitats. The case of bears and raccoons are well-known examples.
Can affect wild animal behaviours
To overcome the challenges that emerge when living close to or within cities, wildlife must adapt their behaviours to the new environment. One hypothesis is that urban individuals become more innovative and bolder than their rural counterparts. To identify these changes within populations, the behaviours of the species in urban and rural areas must be compared.
A German study found that a species of mouse in urban areas tends to be bolder and more exploratory compared to its rural counterparts. Similarly, bullfinches in urban areas have been observed to be bolder and quicker at solving problem-solving tasks, suggesting they are more innovative than bullfinches in the rural environment.
The Case of the Fox
Foxes in cities could also be impacted by the urban environment, particularly in their foraging behaviours as they increasingly rely on anthropogenic food sources. Accessing these resources, such as those found in bins, bird feeders, and other types of containers, often requires problem-solving and innovation from the foxes.
Experiment explanation
The scientist Blake Morton conducted a study in UK to compare the boldness and the problem-solving ability of the red foxes in urban and rural areas. To achieve this, he and his team designed problem-solving tasks that required the foxes to access a food reward. They constructed eight types of food-related objects, each requiring the foxes to push, lift, slide, or pull a part of the object to retrieve the reward inside. Exposing the foxes to these new objects allowed Blake Morton to measure their boldness, as boldness can be assessed through neophobia, the fear of novel objects. I illustrated the different types of food-related objects, the foxes had to used four technique types: lift, push, slide, and pull:
Below, you can find a video example showcasing the objects and the experimental setup:
Results
In both areas, when the novel object was absent, foxes ate the food displayed on the floor, indicating that they were inclined to consume this type of food. However, this behaviour was less frequently observed in the presence of an object. Blake Morton found that foxes in urban areas were significantly more likely to interact with the food-related objects than their rural counterparts. The researcher also observed that, although urban foxes were bolder and touched the objects, they were not more innovative, as they did not solve the problems presented to them significantly more. Solving the problem required the fox to access the food reward at the end. The fact that urban foxes interacted more with the food-related objects but did not persist in solving them may be because they had also easier access to alternative food sources nearby.
Below, you can find a video showing foxes solving the food-related objects:
Conclusion
In the experiment of Black Morton, urban foxes demonstrated greater boldness compared to the rural foxes but were not more innovative in solving problems. This boldness likely stems from the need to adapt to urban environments, where interacting with novel objects is essential for accessing food resources. However, the lack of increased innovation suggests that urban foxes may rely on other strategies, such as opportunistic foraging or accessing easier food sources.
Sources:
Bateman, P. W., & Fleming, P. A. (2012). Big city life: carnivores in urban environments. Journal of zoology, 287(1), 1-23. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-7998.2011.00887.x
Audet, J. N., Ducatez, S., & Lefebvre, L. (2016). The town bird and the country bird: problem solving and immunocompetence vary with urbanization. Behavioral Ecology, 27(2), 637-644. https://doi.org/10.1093/beheco/arv201
Dammhahn, M., Mazza, V., Schirmer, A., Göttsche, C., & Eccard, J. A. (2020). Of city and village mice: behavioural adjustments of striped field mice to urban environments. Scientific reports, 10(1), 13056. https://www.nature.com/articles/s41598-020-69998-6
Morton, F. B., Gartner, M., Norrie, E. M., Haddou, Y., Soulsbury, C. D., & Adaway, K. A. (2023). Urban foxes are bolder but not more innovative than their rural conspecifics. Animal Behaviour, 203, 101-113. https://www.sciencedirect.com/science/article/pii/S0003347223001689
Blacke Morton’s website: https://www.blakemorton.co.uk/
