Human activity is fundamentally changing the distances the world’s animals need to move to live, hunt and forage, according to a study that examined the impact on more than 160 species across six continents.
All activities altered the animals’ behavior, but the study found that destructive activities such as urbanization and logging affected animal movement less than sporadic endeavors such as the use of aircraft, hunting and recreation.
In addition to having a profound effect on animals – such as reducing their ability to feed and reproduce – the changes “signal a global restructuring of animal movement” that could have profound effects, he says. A study published today in Nature Ecology and Evolution magazine.
Dr Tim Doherty, a wildlife ecologist at the University of Sydney, said it was already known that humans influenced animal movement, with thousands of studies tending to focus on individual species or activities, but the information was mixed and it was not. Synthesized.
Doherty personally read abstracts of 12,000 research articles extracted from academic journals around the world, before joining his colleagues to pull out 208 related studies with enough useful data on how human activity changes the distances moved by 167 different species.
When human activities forced animals to move further, such as when animals fled poachers or had to negotiate roads or avoid skiers or campers, they moved at a rate of 70% more in response.
“In Australia, the average person commute is about 16 kilometers, so 70% is like traveling an extra 11 kilometers,” Doherty said.
“If the animals do not move in a normal way, there is potential for wider effects.”
The animals and antiquities examined included:
The Madagascar lemur expands its native range by more than half in response to logging
Brushed opossums in Victoria, Australia, moved 57% in subdivided areas compared to large forests.
In Sweden, moose moved the fastest 33 times an hour after being disturbed by cross-country skiers
Texas turtles traveled fewer distances in cattle grazing areas
Mountain lions in the United States moved more slowly if they heard human voices, which in turn increased the distances rodents moved in the same area.
New Zealand’s no-frills birds that help disperse seeds have covered about a third of the lesser distance in areas near the campgrounds.
Reindeer in Canada move faster in response to noise than oil drilling.
The research says: “Even a small change in movement can have major impacts on an individual, and when these costs accrue across an entire population, fertility rates and population capacity may be at risk.”
Tracking changes in movement was important, as this showed how animals’ behavior changed while fleeing humans or predators or traveling in search of food, shelter, or friends.
Some activities tend to shorten the distances the animals traveled, such as urbanization, making it easier to find food for some animals.
Doherty, who started the research while at Deakin University, told The Guardian: “We found that about a third of the data we discovered reported a change in movement of 50% or more.
“This tells us that as humans we have a very broad influence on animals, but these matters will not be addressed.”
Birds moved at a rate of 27% more in response to human disturbance, with mammals increasing by 19% and bugs 38%.
For mammals, roads, agriculture, and aircraft had the greatest impact on distances traveled, as herding and hunting tend to broaden the local range of the species.
“Humans have disturbed most of the Earth’s surface,” Doherty said. “But there are some places that have not been protected and must be protected.” “We need some places on Earth where animals can be left to do their own thing.”
last year Study found wild places They were disappearing on a massive scale, as in just 13 years an area the size of Mexico was transformed from nearly intact landscapes to areas that have been heavily modified by humans.
Professor Corey Bradshaw, director of the Global Environment Lab at Flinders University in South Australia who was not involved in the latest research, said the study confirmed much of what was known, but provided a “useful summary”.
“The increased mobility of most species in response to disturbance gives an interesting hint regarding the mechanism of human stresses that go beyond the obvious, such as invasive predators, loss of habitat, or direct exploitation.”
Bradshaw said the study also demonstrated how difficult it is to predict how an animal’s local scale could change once human activities begin.
One of the aspects that revealed the study, he said, was the discovery that disturbance from recreation and hunting causes species to move more than habitat loss or fragmentation.
This then indicates that even so-called ‘non-invasive’ human existence can be harmful.