The results of the research
The results of a study conducted on a global scale which analyzed the impact of changes in human activities induced by COVID-19 pandemic (between 2019 and 2021) on the habits of wild mammals. The effects observed vary depending on the environmental context, size and diet of the species studied but in general it was observed that when human activity returned after the lockdowns in the most intact natural environments, mammals reduced their activity by avoiding people, while in more anthropized environments they were more active, but also more nocturnal. Furthermore, large carnivores were found to be the most sensitive to changes in human activity. The study involved more than 220 researchers in 21 countries, including 5 Italian institutions (MUSE – Science Museum, FEM – Edmund Mach Foundation, University of Florence, University of Siena and ISPRA), and investigated the activity of 163 species of mammals with the use of over 5 thousand camera traps, mostly located in the northern hemisphere of the globe.
A uniform response
“Restrictions on people's mobility – a first-of-its-kind event – have allowed zoologists and ecologists to study how animals respond to drastic and rapid changes in the number of people in their habitat,” said the study's first author, Professor Cole Burton of the University of British Columbia in Canada. Burton further states: “What we found was not a uniform response of animals to these changes, but rather variation in effects based on the type of environment and ecology of the mammals studied, the landscape and the species' position in the food chain ”. Large carnivores and large omnivores (such as bears and wild boars) were the most sensitive to changes in human presence linked to COVID-19 restrictions: large carnivores showed a marked tendency to avoid people when they returned to frequent the natural areas, while large omnivores showed a reduction in their activity upon the resumption of human presence in urban and suburban contexts.
Natural environments and anthropized environments
The study highlighted a clear difference between natural environments and anthropized environments in tolerance to humans and the risks associated with the presence of people. Upon the resumption of human activities, species present in environments intensely modified by humans, such as urban and suburban areas, increased their movements, but became more nocturnal, thus suggesting that despite the availability of "artificial" food sources, wild mammals they try to minimize the possibility of meeting humans by moving their activities to the hours of darkness. On the contrary, the animals present in the most natural and uncontaminated areas, which often represent refuges for the most sensitive species, responded to the return of people by avoiding them and decreasing their activity. The results combine with other studies to document a general tendency towards an increase in the nocturnality of mammals forced to cope with a strong human presence, and the data collected indicate that this effect is more marked for species subject to hunting.
Mammals in the Anthropocene: measures and strategies to reduce conflicts
The results of the research allow us to develop measures aimed at reducing disturbance of wildlife and preventing conflicts between humans and wild animals in an era, the Anthropocene, characterized by the pervasive and growing impact of human action on the biosphere. In the most intact natural areas, where infrastructure and urbanized spaces are limited, the effects of human presence on wildlife can be particularly significant, and this also concerns recreational activities such as hiking. To give wild animals the space they need, the study suggests limiting people's access to some areas of protected areas, establishing protective corridors that favor their movements, or even providing seasonal restrictions with temporary closures of some paths during the migratory or breeding seasons. Fauna protection strategies, it is proposed, must be defined on the basis of the analysis of the species present and the places involved: in areas where people and animals overlap more, such as peri-urban areas, the night is an important refuge for wild mammals. Efforts could therefore focus on reducing conflicts with wildlife after dark, such as better management of rubbish bins, or the use of mitigation measures on roads to reduce collisions with vehicles.
The results emerging from this study are particularly significant given the large increase in travel and leisure activities recorded globally since the end of the pandemic.
The five Italian institutions involved in the study:
MUSE - Trento Science Museum
Edmund Mach Foundation – FEM, San Michele all'Adige (TN)
University of Florence – Department of Biology
University of Siena – Department of Life Sciences
ISPRA - Higher Institute for Environmental Protection and Research
LOCAL FOCUS
Western Trentino
In western Trentino the research was concentrated in the study area which has been monitored every summer since 2015, an area that goes from the western borders of the Municipality of Trento to Val Rendena, including Paganella, Gazza and the southern part of the Dolomite massif of Brenta. 60 camera trap sites analyzed by MUSE researchers in collaboration with the University of Florence. Francesco Rovero, professor of ecology at the University of Florence, and Marco Salvatori, researcher in ecology at the same university and the MUSE - Science Museum of Trento, coordinated the data collection for western Trentino, and underline how "the monitoring systematic and long-term that we carry out in the area included in this study, as in other Italian natural areas, has allowed us to clarify some specific aspects of the responses of wild mammals to human presence. In the Italian areas we study, the largest mammal species appear to be the most sensitive to human presence, with clear evidence of avoidance, and are able to express diurnal behavior only where the passage of hikers is low and the distance from population centers is high. The smaller species, on the other hand, tend to be more permanently nocturnal, and more opportunistic, showing themselves to be more active where human passage is intense. Contributing the data we collect in target areas to research on a global scale like this and in conjunction with such particular situations as those generated by the COVID pandemic, can help us understand the consequences of our activities on the different species with which we humans coexist."
Anthropic areas in eastern Trentino and EuroCaM
In eastern Trentino, the research focused on data from the study area in Val di Cembra, in the Argentario area, which has been monitored by the Edmund Mach Foundation since 2017. The sites are characterized by a notable anthropic presence, linked to forestry and especially mining, as well as inhabited areas. Francesca Cagnacci, together with the team of the Animal Ecology Unit for which she is responsible, underlines the importance of medium-long term studies to better understand the human-fauna relationship in an anthropic environment: "We monitor the area almost continuously for several years, starting from a collaboration with the Trentino Hunters Association to evaluate the effect of the practice of supplementary foraging on ungulates, in particular roe deer. Maintaining camera trapping sites for so long has allowed us to study the behavioral response of roe deer, deer and other mammals to various environmental variations, including food availability and the presence of other species. Above all, it made us 'ready' to study the effect of unexpected events that could have induced a change in behavior, such as heavy snowfall or the absence of human presence following lockdowns during the pandemic. Having to follow the study, I had the opportunity to verify firsthand how the environmental perception was different in that period, especially the silence of the forest due to the absence of anthropic noises. In general we observe a great plasticity on the part of these animals, accustomed to the human presence. However, our camera traps also did not observe an increase in daytime use of the areas monitored during the lockdown." The Animal Ecology Unit, and in particular Simone Dal Farra and Federico Ossi, also contributed to the project by organizing the camera trap data of the European Euromammals/EuroCaM network, coordinated by FEM, liaising with Canadian colleagues.
The mammals of the Maremma Regional Park
The Maremma Regional Park is one of the areas included in the study and has for many years been the site of a research project on the interactions between mammal species, conducted by the University of Siena with the close collaboration and support of the Park Authority. The data collected flowed into the European Euromammals/EuroCaM network, coordinated by FEM, and contributed to the global study. Francesco Ferretti, professor at the Department of Life Sciences of the University of Siena, highlights: "Sixty camera trap stations have been monitored regularly in the Maremma Park for several years with the aim of analyzing the interactions between the various species, such as ungulates and carnivores, and detect their dynamics over time. This monitoring continuity is important because it can also allow us to identify the possible responses of wild animals to any environmental changes. For example, in periods characterized by restrictive measures on people's movements, the presence of an active monitoring network using camera traps made it possible to collect useful information to evaluate any variations in the activity of the various animal species in relation to different human attendance. Ferretti continues: "Even in this area, no uniform responses were found among the animal species investigated and we did not observe a generalized increase in daytime activity" (source: FIDC).