A recent study published in Ecology and Evolution has revealed significant dietary differences between urban and rural red foxes (Vulpes vulpes) across Britain, shedding light on how urbanisation is influencing the behaviour and ecology of this adaptable species.
Research Overview
Led by a team from Nottingham Trent University, the research utilised stable isotope analysis (SIA) of whisker samples to examine the long-term diets of red foxes living in contrasting environments. The technique allowed scientists to quantify the proportion of human-derived food sources in the foxes' diets, offering a unique window into how urban living is shaping their foraging strategies.
Striking Differences in Diet
The results show a marked contrast between foxes living in cities and those in the countryside. Urban foxes were found to consume significantly more human-related food than their rural counterparts. On average:
Urban foxes obtained approximately 34.6% of their diet from human-derived sources.
Rural foxes relied on human-related foods for just 6% of their intake.
In cities, this included about 16% human food waste and 19% pet food, while rural foxes consumed far less—2.5% and 3.5%, respectively.
Despite this, both groups continued to depend heavily on natural food sources such as birds, mammals, and invertebrates, with rural foxes showing a particularly strong preference for these.
Sex and Seasonal Trends
Interestingly, the study also identified some variation based on sex. Female foxes appeared to consume more human-derived food, possibly due to higher energy demands during cub-rearing periods. The findings also suggested some seasonal variation in diet, with foxes in urban areas potentially increasing their reliance on human food sources during colder months when natural prey may be scarcer.
Health and Conservation Concerns
While the availability of human food offers urban foxes an abundant and accessible resource, the nutritional value of these items is questionable. Diets high in processed foods, saturated fats, and sugars may not meet the species' dietary needs and could have negative impacts on their health and longevity.
This raises important questions about the long-term implications of urban foraging, not only for foxes but for other wildlife increasingly exposed to anthropogenic food sources.
Our Perspective: Social Media & Feeding Culture
In our view, the growing trend of fox-focused social media groups—many of which treat hand-feeding wild foxes as a form of competition or personal validation—is playing a troubling role in encouraging direct and sustained human interaction. While often fuelled by affection for these animals, this behaviour actively promotes the consumption of diets that are wholly unsuitable for foxes.
Processed human foods, takeaway scraps, and pet food may be readily accepted, but they do not meet the nutritional needs of a wild canid. Despite this, such items make up the majority—if not the entirety—of the daily diet for many urban foxes. This shift away from natural foraging may result in poor health outcomes, reduced fitness, and developmental challenges for cubs.
Additionally, when concentrated food sources are repeatedly provided in specific urban zones, they can encourage unnaturally dense fox populations with limited dispersal. This can lead to inbreeding, a reduced gene pool, and a heightened risk of disease transmission—factors that may compromise the long-term viability of urban fox populations.
Crucially, by encouraging this dependency on human food, we are also impeding foxes from fulfilling their ecological role. Urban areas are not devoid of natural food—far from it. Cities are among the highest in rodent populations, and foxes are well-adapted to controlling rats, mice, and other urban pests. By feeding them instead, we’re not only harming their health but removing a key natural control mechanism from the urban ecosystem.
We strongly advocate for a different approach: creating environments that support foxes naturally. This includes planting native species, preserving wild spaces, and allowing gardens and green corridors to develop with biodiversity in mind. Urban foxes don't need us to feed them—they need us to protect and restore the ecosystems that allow them to thrive independently.
A Call for Responsible Waste Management
The findings underline the critical role of human behaviour in shaping wildlife ecology. Poor waste management, easily accessible rubbish, and the unintentional (or intentional) feeding of foxes are all contributing factors to their reliance on human food.
As urban fox populations continue to grow, the researchers stress the importance of responsible waste practices, urban planning that takes wildlife into account, and further studies into the health effects of human-influenced diets on wild animals.
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