Photo: Jacob King/PA
Humans weren’t the only ones who developed bad habits during lockdown. According to new research, some primates in zoos became more solitary and sedentary, while others exhibited more sexually and physically dominant behavior.
The study compared the behavior of bonobos, chimpanzees, baboons and gorillas at a zoo and safari park in 2020, when they were hidden from people’s view during the lockdown, to their behavior once visitors have returned.
Olive baboons displayed less sexual and dominant behavior when visitors came back than they had displayed during the lockdown, the researchers observed.
They also approached visitor cars more frequently than the ranger vehicle when the park was closed.
The study, published in Animals journal, found bonobos and gorillas spent less time alone and gorillas less time resting when visitors returned.
The chimpanzees studied ate more and were more engaged with their enclosures when the zoo was open.
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Whether lockdown experiences were positive, negative, or neutral for individual animals is difficult to say, the scientists said, but the chimpanzees and baboons appeared to be purposefully stimulated by the return of visitors.
Bonobos and gorillas, who spend less time alone, could also be rated positively.
But the reduction in resting behavior in more sedentary gorillas could also indicate they have been disturbed by visitors, the researchers say.
The gorillas changed how their enclosure was used, suggesting they were able to modify their behavior to reduce potential overstimulation and effectively manage their own experiences, the research found.
According to the results, the olive baboons may have been stimulated by visitors and the presence of cars, but there was a threshold after which this stopped increasing.
The study also reports that their increased sexual behavior during the closure may have been due to not being stimulated by the presence of moving vehicles.
dr Samantha Ward, zoo animal welfare scientist at Nottingham Trent University’s School of Animal, Rural and Environmental Sciences, said: “Primates are among the most cognitively advanced species in zoos and their interactions with visitors are complex.
“One limitation of understanding how visitors can influence the behavior of animals in zoos and parks is that they are rarely in the public eye for long periods of time, so this presented us with a unique opportunity.”
Related: ‘It’s a sad day’: Bristol Zoo welcomes last visitors ahead of closure
According to experts, the interactions between humans and animals as well as the effects of the presence of zoo visitors are considered crucial for animal welfare.
Research has shown that different species and even individual animals respond differently to different people.
dr Ellen Williams, zoo welfare researcher at Harper Adams University, said: “Our study demonstrated the multiple ways in which visitors can influence the behavior of primates in captivity.
“Behavioural changes and changes in enclosure use in the presence of visitors illustrate the adaptability of zoo species to their environment.
“Providing environments that allow animals to actively adapt in this way is really important to their welfare.”
Behavioral data for the study was collected between April-September 2020 and November 2020-January 2021 and spanned multiple open and closed periods during the coronavirus pandemic.
Bonobos, chimpanzees and gorillas have been observed at Twycross Zoo in Leicestershire, while baboons have been monitored by staff at Knowsley Safari in Merseyside.