Be wary of the ‘beautiful threat’ of invasive alien species
While cute, cats, parrots and raccoons are also invasive species in some cases. However, do you have the heart to drive away these cute creatures?
In the 1950s, someone brought several cats to the French Kerguelen Island, said to be to deal with the rabbits that gnawed on the vegetation on the island and the rats that the victims inadvertently brought to the island. However, in just a few decades, these cats have multiplied to more than 4,000, and now 1.2 million birds die every year. There used to be 400,000 birds in New Zealand’s Hilkopal Islands, but since cats began to live in this land, six land bird species on the island have become extinct because of cats, and many seabirds have also been unable to fly due to the presence of natural enemies Live on the island, and now there are only a few thousand birds left on the island. The IUCN ranks cats as one of the 100 most invasive alien species in the world, along with rats, of course. Having said that, cats are cute and interesting in everyone’s eyes. Can we really be cruel and treat cats like street mice?
How exactly does the charisma of species affect their invasion of other ecosystems? An international research team has carried out the study, which also involved two laboratories in France. On April 6, 2020, the team published an article in the academic journal “Frontiers of Ecology and Environmental Sciences”, saying that the popularity of species and social perception of them will determine whether they can be introduced into new environments and people’s subsequent understanding of them. its acceptance.
The destruction of natural habitats is often due to the destruction of local biodiversity by invasive alien species. In 2016, an article in “Biology Letters” stated that the extinction of many plants, amphibians, reptiles, birds and mammals in recent years is inseparable from the invasion of alien species. The article pointed out that “more than half of the species extinction phenomenon is related to the invasion of alien species, and the extinction of a large number of vertebrates is also attributed to this
” Plants with a long flowering period will be favored by humans. The research team stated in the report, “The charm of a species refers to some of their dispositions or behaviors that win the favor of humans.” ” and other characteristics, human beings will pay special attention to them. The report finally draws a conclusion: Whether it is when invasive species are first introduced, or in the process of their subsequent reproduction, or even after people finally realize that they need to be controlled and studied, the charm of invasive species is irrelevant at any stage. play a role that cannot be underestimated.
People often actively introduce a species for aesthetic reasons, such as ornamental plants, ornamental fish and companion animals. One-third of the aquatic invasive alien species that are most harmful to the economy and ecology are ornamental fish. “The more attractive an invasive alien species is, the more likely it is that people will introduce it on a large scale,” said Franck Courchan, a researcher at the French National Center for Scientific Research and co-author of the Frontiers in Ecology and Environmental Sciences article. High; the greater the number of introductions, the higher the probability that they will successfully establish a base in the new environment. If those invasive species are cuter and closer to humans, it will be more difficult for people to detect the harm caused by their reproduction in time.”
The Florida painted tortoise in the United States is a typical example. European pet stores once frantically imported a large number of this kind of tortoise because of their “appearance”. Another example is raccoons. Japan has introduced a large number of raccoons for a while, which stems from people’s love for the image of raccoons in an anime. 20 years ago, the introduction of ring-necked parrots to the European flower and bird market is the same. Today, ring-necked parrots can be seen from southern Spain to the United Kingdom. They not only occupy the living space of native birds, but also attack seagulls and Bats, destroying vineyards and orchards. “When the ring-necked parrot was first introduced and hadn’t established itself, people didn’t have any reaction.” Kurchan said, “There is no doubt that people are attracted by the beauty of the ring-necked parrot.”
In their paper, Kurchan et al. also show that the more attractive people find an alien species, the more likely they are to support that species’ establishment in their neighbourhood. If the government wants to take measures to control this species, it may encounter opposition from the masses. Sergey Muller, an expert on biological invasions, said, “This article reflects the current difficulties in controlling some invasive alien species.”
”Some invasive alien species have some attractive characteristics.” Social ecologist , Anne Atlan, research director of the French National Center for Scientific Research, said, “This is why we say that governance of these species is full of contradictions. Some social groups think it is good for them to come, but at the same time, ecologists and naturalists. Groups such as the Guardians hold the opposite view. That’s why controlling species can be so controversial.”
| Gray and Red Squirrels|
A very representative example is the American gray squirrel which has gradually invaded the UK in recent decades. Meanwhile, gray squirrels approached the south of England step by step, while the number of local red squirrels began to decline sharply. There are many reasons. Compared with red squirrels, gray squirrels are better at finding hazelnuts and are more aggressive. What’s more terrible is that gray squirrels are asymptomatic carriers of a virus, but this virus can kill red squirrels. The life of a squirrel. In addition, gray squirrels are bolder than red squirrels. As long as they are fed in the park, they will run to eat them, which also makes local people think gray squirrels are more lovable.
When gray squirrels were first introduced to Italy, invasive alien species experts tried to reverse the trend, but animal protection groups launched a campaign that rejected their proposals. A few years later, the proposal, once shelved by experts, was finally adopted, but by this time the gray squirrel had established itself in most of Italy.
”Fighting invasive alien species has never been an easy task. If we do not eradicate invasive alien species, the survival of native species will be threatened. This is true, but it is not easy to explain to the public.” Kurchan said frankly “It’s counterintuitive to say that we have to exterminate living plants and animals in order to protect biodiversity, since there is no such thing as a ‘bad species’, let alone invasive species that people love. And eradicating them is more controversial.”
Atlan has a different view on the issue of invasive alien species. In her view, we should take society’s attitudes into account when dealing with invasive alien species. Eliminating invasive alien species should not be the only way we deal with them. She argues that at least in some cases, there is another form of control. “After alien species integrate, we can even take a laissez-faire attitude and let them form new ecosystems with native species. We can also explore the economic value of new species.” She explained, “Why do we have to drive them away? What about protecting native species at the expense of the species that people love?”
Researchers such as Kurshan hope to let more people understand the impact of the charm of alien invasive species on people. In this way, people can hopefully better appreciate potential threats and avoid them. As Muller puts it: “People in the know know this phenomenon, but the public has not yet realized that beautiful and beautiful species can also cause big trouble.”