Scientists are calling on conservationists to take the “charisma” of invasive species into consideration when managing the biological threat posed by them.

The charisma of an invasive alien species refers to its popularity and its perception by society and the media.

The researchers outline their concerns in what they describe as a “concept and question” paper published in the journal Frontiers in Ecology and the Environment, saying these species may pose a threat to the biodiversity in the regions where they were introduced.

Biological invasions are considered the second cause of recent species extinctions

Franck Courchamp, a researcher at the National Centre for Scientific Research (CNRS) in Paris who specialises in conservation biology and one of the study authors, told the PA news agency: “Biological invasions are considered the second cause of recent species extinctions, the current second threat to biodiversity, and the reason for an economic cost of hundreds of billions of dollars every year globally.”

He added: “We propose a claim that the charisma of species is likely to favour their invasion and we examine it under evidence of different aspects and processes with examples.”

For example, the researchers said, the arrival of the popular North American grey squirrel in Italy threatens the existence of the native red squirrel, but the emotive messages used by the media and animal campaign groups in response to a plan to control the population of the grey squirrel led to public opposition and long-drawn legal battles.

Meanwhile in the UK, the ruddy duck was adopted as the emblem of a birdwatchers’ club 50 years after it was introduced from North America, although numbers have reduced drastically in the recent years.

And the prickly pear, introduced from Central America to Europe by the Spanish conquerors, have become iconic symbols in the Spanish landscape, featuring on stamps and postmarks.

According to the team, examples like these show many alien species are considered desirable and might even be subject to protection or restoration measures in situations where they are threatened or suffer population declines.

The researchers describe charisma as “a highly relevant concept for invasion science”, with “implications across all stages of the invasion process”.

The team wrote in their paper: “Charisma can, and historically has, affected species introductions, media portrayal, public perceptions, opposition to management, research effort, and public participation in research and management.”

They added explicit consideration of charisma of invasive species is “critical for understanding the factors that shape people’s attitudes toward particular species”.