Why is it in news?

A study indicates that foreign invasive species may be on the rise across the world.

Details

• The number of newly emerging alien species continues to rise, posing a significant challenge to biosecurity interventions worldwide, according to a study. Alien species are those that do not belong to a region and introduced intentionally or accidentally by humans.
• Researchers, including those from University College London (UCL) in the UK, found that up to 16 per cent of all species on Earth may be alien species and if they invade new regions, impacts will be difficult to predict.
• Approaches to tackle the growing issue largely rely on knowledge of species’ invasion history elsewhere, giving new previously unrecorded alien species a higher chance of slipping through border controls and eluding early response management
• The study, published in the journal PNAS, analysed a global database of 45,984 records detailing the first invasions of 16,019 established alien species from 1500 until 2005 to investigate the dynamics of how alien species spread worldwide. Between the years 2000 and 2005, one quarter of records are of species that had not previously been found anywhere as an alien, which is a worryingly high proportion.
• For plants, mammals, and fishes, the proportion of newly emerging alien species has remained constant during the last 150 years but the total number of alien species has increased. Insects, molluscs and other invertebrates have the highest proportion of emerging alien species. Birds are the only group exempt from the trend, showing the lowest proportions of emerging alien species, with a distinct decline noted recently.
• Humans have been moving species to new places for thousands of years and it has been identified as a prime reason for growing invasions for foreign species across the world.

About Invasive species

• An invasive species can be any kind of living organism—an amphibian (like the cane toad), plant, insect, fish, fungus, bacteria, or even an organism’s seeds or eggs—that is not native to an ecosystem and causes harm.
• They can harm the environment, the economy, or even human health.
• Species that grow and reproduce quickly, and spread aggressively, with potential to cause harm, are given the label “invasive.”

Source

The Hindu