Bird watching and animals tagged with GPS trackers show that more than a quarter of them die by the hand of man that makes people one of the main threats to the survival of all nature. Write about the scientists, who published an article in the journal Global Ecology and Biogeography.
“We all know that humanity has a negative impact on wildlife, but we got the first accurate estimate of how much. We are one of 35 species of vertebrate animals living on land, but on our account for about a quarter of all their deaths. And this is only the direct death, without taking into account urban growth, and other manifestations of civilization,” said Jerrold Belant (Jerrold Belant) from Purchase College in new Iroke (USA).
Scholars in the history of life on Earth, five major mass extinctions of species. The most significant is considered to be “great” Permian extinction, when they disappeared more than 95% of all living creatures inhabiting the planet, including fancy zoroastro, close relatives of the ancestors of mammals, and a number of marine animals,reports RIA Novosti.
Three years ago, environmentalists said that now on Earth there is a sixth mass extinction of animals. According to their calculations, in the era prior to the anthropocene – age of man, every hundred years, disappeared for about two mammal species, for every ten thousand of the then existing species of animals. In the XX and XXI centuries, this figure rose to 114 times.
Belant and his colleagues have estimated the contribution of humankind to this process, using data collected by dozens of other ecologists in the course of observing the life of various species of mammals, birds, reptiles and amphibians that are marked with GPS trackers.
In total, scientists were able to collect data on the fate of the approximately 120 thousand different inhabitants of the land, which included approximately three hundred species of warm-blooded and cold-blooded animals. A little more than 42 thousand of them were killed during supervision, enabling environmentalists to assess the human role in their death.
As it turned out, almost 12 thousand of these deaths were directly related to the person, and more than half of these cases were related to poaching or other illegal forms of hunting. Only 17% of cases, killers of animals, marked by beacons, had the license for their shooting, and only 5-10% of deaths were related to accidents, human-induced infections and other accidental causes of death.
Most interestingly, the proportion of deaths associated with a person grow smoothly along with the weight of the animals for large mammals it was close to 50%, whereas for amphibians, young reptiles and small birds it was below 10%. This goes well with the typical preferences of hunters and poachers.
As researchers emphasize, these figures likely represent a very conservative estimate, as most observations were conducted in the USA and Canada, where there are serious restrictions on hunting where poachers regularly persecuted.
In addition, they do not take into account how a lot of wildlife kill cats and other domestic animals, invasive species, and pesticides and various other forms of toxins produced by man.In addition, it is not clear how the mass hunting of various large animals impacts on their evolution and adaptation to the environment. It is possible that such “artificial selection” can accelerate their disappearance in the future, when the planet’s climate will change even more, the authors conclude the article.