Polish Institute Classifies Cats as 'Invasive Alien Species'

A 2019 study published in Global Ecology and Conservation, an international scientific journal, said that cats, when allowed to roam outside on the streets and in parks, kill more than 630 million mammals and more than 140 million birds in Poland every year.

A scientific institute in Poland, The Polish Academy of Sciences, has labeled household cats an "invasive alien species" in a decision taken after scientists noted that cats cause damage to birds and other animals.

Felis catus, the scientific name for the house cat, became the 1,787th species in the national Polish database to be categorized as an "invasive alien species".

Wojciech Solarz, a biologist at the state-run Polish Academy of Sciences, said cats threaten global diversity and disrupt the ecosystem.

Solarz also said that the feline is "100 percent" in the category of alien invasive species.

The claim about cats, however, appears to have offended some cat lovers.

"Ask if a man is on the list of non-invasive alien species," Dorota Suminska, an author of a book titled The Happy Cat who is infuriated by the claim, told the Washington Post.

According to Solarz, cats must have been domesticated around 10,000 years ago in the Middle East, which makes them non-native to Europe or "alien species" for Europe from "a strictly scientific point of view."

While domestic cats might be a relative newcomer in Europe, the European wildcat, which can no longer be found in Poland, inhabited the continent for hundreds of thousands of years before the arrival of Homo Sapiens.