The coexistence of wildlife and people in Europe’s human-dominated landscape is a complex phenomenon. Protected areas are relatively small and intermingle with regions of high human disturbance. This leads animals to use various adaptation mechanisms, including increasing their nocturnal activity. A recent study, supported by the Polesia project, is the first to analyse the diurnal activity of wolves and lynx along a gradient of human disturbance. The findings shed light on how human presence correlates with changes in these animals’ temporal behaviours.
A growing human presence in wildlife areas is particularly critical for large carnivores with large home ranges, such as the wolf and Eurasian lynx. Increasing nocturnal behaviour is one way these animals avoid risky interactions with humans. While previous research has described this adaptation, this study is the first to analyse the diurnal activity of these species across multiple areas with varying levels of human activity, from areas of intense anthropogenic pressure to those where human activity is highly restricted. This approach offers valuable insight into how human disturbance influences wildlife.
Why understanding animal behaviour matters
Understanding the behaviour of large carnivores and the factors that cause them to change their mode of living is important from a number of perspectives. On one hand, if human disturbance causes carnivores to shift their activity to the nocturnal period, this could affect their interactions with prey, with potentially significant consequences for the ecosystem. On the other hand, in human-dominated landscapes, nocturnal behaviour reduces negative human-animal interactions and so benefits the conservation of carnivores by enabling their conflict-free coexistence.
These findings challenge assumptions about the nature of wolves. One of the study’s authors, Adam Francis Smith, Research and Monitoring Coordinator at the Frankfurt Zoological Society, explains: “It is common to assume that wolves are just creatures of night time, but ultimately it is our impacts on the landscape, mostly during daytime, which confine them to night. Wolves are intelligent and adaptable to different human pressures. However, Eurasian lynx are mostly ambush predators, so being active at night fits their predation mode very well.”
This distinction between the two species underscores the importance of studying how different carnivores respond to human activity and the broader ecological implications.
A novel approach to studying carnivore activity
Previous studies have demonstrated that wolves and lynx in Europe are predominantly nocturnal. However, they have not explored how diurnal behaviour varies between regions with different levels of human disturbance. This new study fills that gap.
Researchers hypothesised that wolves and lynx would be more active during the day in areas with low human activity and that nocturnal activity would increase with greater human disturbance. To test this, they analysed camera trap data from nine sites across six European countries. These sites represented a spectrum of human disturbance, ranging from areas with restricted access to those with high levels of human activity.
Two key sites were in Polesia: the Ukrainian Chornobyl Exclusion Zone and Pripyat-Polesia in Belarus. The Chornobyl Exclusion Zone, where human activity has been minimal since the 1986 nuclear disaster, served as the baseline for understanding wolf and lynx behaviour in low-disturbance conditions. Camera traps were also deployed in Belarusian Pripyat-Polesia, Poland’s Białowieża Primeval Forest and Tuchola Forest Complex, Bieszczady and Skolivski Beskydy National Parks in Ukraine, Germany’s Bavarian Forest National Park, Croatia’s Plitvice Lakes National Park, and Italy’s Maremma Regional Park.
Key findings
Data collected between 2014 and 2022, focusing on the monitoring season (September to April), included over 71,000 independent encounters: 2,430 with wolves, 934 with lynx, 8,585 with prey species, and 59,408 with humans. Human encounters were highest in Germany’s Bavarian Forest National Park and lowest in Ukraine’s Skolivski Beskydy National Park and the Chornobyl Exclusion Zone.
The study revealed that wolves were generally nocturnal but showed more daytime activity in areas with less human disturbance. In the Chornobyl Exclusion Zone, wolves were the most diurnal, followed by those in Skolivski Beskydy and Białowieża National Parks. Conversely, wolves in Belarusian Pripyat-Polesia were the most nocturnal, reflecting the high level of human activity and year-round wolf hunting in the region.
Lynx behaviour, however, was consistently nocturnal across all sites, suggesting their activity patterns are less influenced by human presence. Interestingly, lynx in Croatia’s Plitvice Lakes National Park showed the most diurnal behaviour, while those in the Bavarian Forest National Park were the most nocturnal. These findings indicate that lynx are more tightly bound to their nocturnal-crepuscular niche (preferring activity at night or twilight), regardless of the level of human disturbance.
According to Smith, if human presence during the day restricts wolves to nocturnal activity, this may have significant implications: “If we confine wolves to night because of human disturbance during the day, we can expect different behaviours. If we want to allow the full range of wolf behaviours—or, in other words, to allow them to choose when to be active—we must decrease our disturbance in time as well as space.”
Why wolves and lynx behave differently
These findings likely stem from differences in predation ecology. Although they often prey on the same species, wolves and lynx have different hunting strategies. As cursorial predators, wolves rely on pursuit tactics. However, they can also use the stalk and ambush strategy, which is most effective in low light conditions. Wolves’ hunting success is generally highest at twilight, but it is likely that some wolves have improved their hunting success at daytime. In addition, the social behaviour of wolves can also influence their way of life, as they can hunt alone or in packs.
As a predominantly solitary, ambush predator, the lynx fits well into the nocturnal-crepuscular niche because darkness allows it to implement its hunting strategy most effectively.
Implications for conservation
Areas of restricted human access in Europe are unlikely to expand in the near future. However, populations of large carnivores like wolves and lynx are increasing and recolonising areas where they were previously extinct. This suggests that these species will continue to exhibit predominantly nocturnal behaviour in areas with high human presence, in order to minimise risky interactions with humans.
Smith emphasises the importance of understanding these behavioural shifts for effective conservation: “The most obvious next steps are to look at how these human disturbances influence other aspects of wolf and lynx biology. For example, is hunting success lower in more nocturnal populations? What about the size of family groups? These are important questions for finding the balance between human disturbance and the capabilities and persistence of large carnivores in Europe.”
This research highlights the need to manage human presence in wildlife habitats to promote conflict-free coexistence. By understanding how large carnivores adapt to human disturbance, we can develop more effective conservation strategies that ensure their survival and a sustainable balance with human activity.
This article was originally posted on the Wild Polesia website. To find out more about the Polesia project, visit their project page. The full study is available here.
